rts/Linker.c

   1 /* -----------------------------------------------------------------------------
   2  *
   3  * (c) The GHC Team, 2000-2004
   4  *
   5  * RTS Object Linker
   6  *
   7  * ---------------------------------------------------------------------------*/
   8
   9 #if 0
  10 #include "PosixSource.h"
  11 #endif
  12
  13 /* Linux needs _GNU_SOURCE to get RTLD_DEFAULT from <dlfcn.h> and
  14    MREMAP_MAYMOVE from <sys/mman.h>.
  15  */
  16 #ifdef __linux__
  17 #define _GNU_SOURCE
  18 #endif
  19
  20 #include "Rts.h"
  21 #include "HsFFI.h"
  22
  23 #include "sm/Storage.h"
  24 #include "Stats.h"
  25 #include "Hash.h"
  26 #include "LinkerInternals.h"
  27 #include "RtsUtils.h"
  28 #include "Trace.h"
  29 #include "StgPrimFloat.h" // for __int_encodeFloat etc.
  30 #include "Stable.h"
  31
  32 #if !defined(mingw32_HOST_OS)
  33 #include "posix/Signals.h"
  34 #endif
  35
  36 // get protos for is*()
  37 #include <ctype.h>
  38
  39 #ifdef HAVE_SYS_TYPES_H
  40 #include <sys/types.h>
  41 #endif
  42
  43 #include <stdlib.h>
  44 #include <string.h>
  45 #include <stdio.h>
  46 #include <assert.h>
  47
  48 #ifdef HAVE_SYS_STAT_H
  49 #include <sys/stat.h>
  50 #endif
  51
  52 #if defined(HAVE_DLFCN_H)
  53 #include <dlfcn.h>
  54 #endif
  55
  56 #if defined(cygwin32_HOST_OS)
  57 #ifdef HAVE_DIRENT_H
  58 #include <dirent.h>
  59 #endif
  60
  61 #ifdef HAVE_SYS_TIME_H
  62 #include <sys/time.h>
  63 #endif
  64 #include <regex.h>
  65 #include <sys/fcntl.h>
  66 #include <sys/termios.h>
  67 #include <sys/utime.h>
  68 #include <sys/utsname.h>
  69 #include <sys/wait.h>
  70 #endif
  71
  72 #if defined(linux_HOST_OS    ) || defined(freebsd_HOST_OS) || \
  73     defined(dragonfly_HOST_OS) || defined(netbsd_HOST_OS ) || \
  74     defined(openbsd_HOST_OS  ) || \
  75     ( defined(darwin_HOST_OS ) && !defined(powerpc_HOST_ARCH) )
  76 /* Don't use mmap on powerpc-apple-darwin as mmap doesn't support
  77  * reallocating but we need to allocate jump islands just after each
  78  * object images. Otherwise relative branches to jump islands can fail
  79  * due to 24-bits displacement overflow.
  80  */
  81 #define USE_MMAP
  82 #include <fcntl.h>
  83 #include <sys/mman.h>
  84
  85 #ifdef HAVE_UNISTD_H
  86 #include <unistd.h>
  87 #endif
  88
  89 #endif
  90
  91 #if defined(linux_HOST_OS) || defined(solaris2_HOST_OS) || defined(freebsd_HOST_OS) || defined(dragonfly_HOST_OS) || defined(netbsd_HOST_OS) || defined(openbsd_HOST_OS)
  92 #  define OBJFORMAT_ELF
  93 #  include <regex.h>    // regex is already used by dlopen() so this is OK
  94                         // to use here without requiring an additional lib
  95 #elif defined(cygwin32_HOST_OS) || defined (mingw32_HOST_OS)
  96 #  define OBJFORMAT_PEi386
  97 #  include <windows.h>
  98 #  include <math.h>
  99 #elif defined(darwin_HOST_OS)
 100 #  define OBJFORMAT_MACHO
 101 #  include <regex.h>
 102 #  include <mach-o/loader.h>
 103 #  include <mach-o/nlist.h>
 104 #  include <mach-o/reloc.h>
 105 #if !defined(HAVE_DLFCN_H)
 106 #  include <mach-o/dyld.h>
 107 #endif
 108 #if defined(powerpc_HOST_ARCH)
 109 #  include <mach-o/ppc/reloc.h>
 110 #endif
 111 #if defined(x86_64_HOST_ARCH)
 112 #  include <mach-o/x86_64/reloc.h>
 113 #endif
 114 #endif
 115
 116 #if defined(x86_64_HOST_ARCH) && defined(darwin_HOST_OS)
 117 #define ALWAYS_PIC
 118 #endif
 119
 120 /* Hash table mapping symbol names to Symbol */
 121 static /*Str*/HashTable *symhash;
 122
 123 /* Hash table mapping symbol names to StgStablePtr */
 124 static /*Str*/HashTable *stablehash;
 125
 126 /* List of currently loaded objects */
 127 ObjectCode *objects = NULL;     /* initially empty */
 128
 129 static HsInt loadOc( ObjectCode* oc );
 130 static ObjectCode* mkOc( char *path, char *image, int imageSize,
 131                          char *archiveMemberName
 132 #ifndef USE_MMAP
 133 #ifdef darwin_HOST_OS
 134                        , int misalignment
 135 #endif
 136 #endif
 137                        );
 138
 139 #if defined(OBJFORMAT_ELF)
 140 static int ocVerifyImage_ELF    ( ObjectCode* oc );
 141 static int ocGetNames_ELF       ( ObjectCode* oc );
 142 static int ocResolve_ELF        ( ObjectCode* oc );
 143 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
 144 static int ocAllocateSymbolExtras_ELF ( ObjectCode* oc );
 145 #endif
 146 #elif defined(OBJFORMAT_PEi386)
 147 static int ocVerifyImage_PEi386 ( ObjectCode* oc );
 148 static int ocGetNames_PEi386    ( ObjectCode* oc );
 149 static int ocResolve_PEi386     ( ObjectCode* oc );
 150 static void *lookupSymbolInDLLs ( unsigned char *lbl );
 151 static void zapTrailingAtSign   ( unsigned char *sym );
 152 #elif defined(OBJFORMAT_MACHO)
 153 static int ocVerifyImage_MachO    ( ObjectCode* oc );
 154 static int ocGetNames_MachO       ( ObjectCode* oc );
 155 static int ocResolve_MachO        ( ObjectCode* oc );
 156
 157 #ifndef USE_MMAP
 158 static int machoGetMisalignment( FILE * );
 159 #endif
 160 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
 161 static int ocAllocateSymbolExtras_MachO ( ObjectCode* oc );
 162 #endif
 163 #ifdef powerpc_HOST_ARCH
 164 static void machoInitSymbolsWithoutUnderscore( void );
 165 #endif
 166 #endif
 167
 168 /* on x86_64 we have a problem with relocating symbol references in
 169  * code that was compiled without -fPIC.  By default, the small memory
 170  * model is used, which assumes that symbol references can fit in a
 171  * 32-bit slot.  The system dynamic linker makes this work for
 172  * references to shared libraries by either (a) allocating a jump
 173  * table slot for code references, or (b) moving the symbol at load
 174  * time (and copying its contents, if necessary) for data references.
 175  *
 176  * We unfortunately can't tell whether symbol references are to code
 177  * or data.  So for now we assume they are code (the vast majority
 178  * are), and allocate jump-table slots.  Unfortunately this will
 179  * SILENTLY generate crashing code for data references.  This hack is
 180  * enabled by X86_64_ELF_NONPIC_HACK.
 181  *
 182  * One workaround is to use shared Haskell libraries.  This is
 183  * coming.  Another workaround is to keep the static libraries but
 184  * compile them with -fPIC, because that will generate PIC references
 185  * to data which can be relocated.  The PIC code is still too green to
 186  * do this systematically, though.
 187  *
 188  * See bug #781
 189  * See thread http://www.haskell.org/pipermail/cvs-ghc/2007-September/038458.html
 190  *
 191  * Naming Scheme for Symbol Macros
 192  *
 193  * SymI_*: symbol is internal to the RTS. It resides in an object
 194  *         file/library that is statically.
 195  * SymE_*: symbol is external to the RTS library. It might be linked
 196  *         dynamically.
 197  *
 198  * Sym*_HasProto  : the symbol prototype is imported in an include file
 199  *                  or defined explicitly
 200  * Sym*_NeedsProto: the symbol is undefined and we add a dummy
 201  *                  default proto extern void sym(void);
 202  */
 203 #define X86_64_ELF_NONPIC_HACK 1
 204
 205 /* Link objects into the lower 2Gb on x86_64.  GHC assumes the
 206  * small memory model on this architecture (see gcc docs,
 207  * -mcmodel=small).
 208  *
 209  * MAP_32BIT not available on OpenBSD/amd64
 210  */
 211 #if defined(x86_64_HOST_ARCH) && defined(MAP_32BIT)
 212 #define TRY_MAP_32BIT MAP_32BIT
 213 #else
 214 #define TRY_MAP_32BIT 0
 215 #endif
 216
 217 /*
 218  * Due to the small memory model (see above), on x86_64 we have to map
 219  * all our non-PIC object files into the low 2Gb of the address space
 220  * (why 2Gb and not 4Gb?  Because all addresses must be reachable
 221  * using a 32-bit signed PC-relative offset). On Linux we can do this
 222  * using the MAP_32BIT flag to mmap(), however on other OSs
 223  * (e.g. *BSD, see #2063, and also on Linux inside Xen, see #2512), we
 224  * can't do this.  So on these systems, we have to pick a base address
 225  * in the low 2Gb of the address space and try to allocate memory from
 226  * there.
 227  *
 228  * We pick a default address based on the OS, but also make this
 229  * configurable via an RTS flag (+RTS -xm)
 230  */
 231 #if !defined(ALWAYS_PIC) && defined(x86_64_HOST_ARCH)
 232
 233 #if defined(MAP_32BIT)
 234 // Try to use MAP_32BIT
 235 #define MMAP_32BIT_BASE_DEFAULT 0
 236 #else
 237 // A guess: 1Gb.
 238 #define MMAP_32BIT_BASE_DEFAULT 0x40000000
 239 #endif
 240
 241 static void *mmap_32bit_base = (void *)MMAP_32BIT_BASE_DEFAULT;
 242 #endif
 243
 244 /* MAP_ANONYMOUS is MAP_ANON on some systems, e.g. OpenBSD */
 245 #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
 246 #define MAP_ANONYMOUS MAP_ANON
 247 #endif
 248
 249 /* -----------------------------------------------------------------------------
 250  * Built-in symbols from the RTS
 251  */
 252
 253 typedef struct _RtsSymbolVal {
 254     char   *lbl;
 255     void   *addr;
 256 } RtsSymbolVal;
 257
 258 #define Maybe_Stable_Names      SymI_HasProto(stg_mkWeakzh)                     \
 259                                 SymI_HasProto(stg_mkWeakForeignEnvzh)           \
 260                                 SymI_HasProto(stg_makeStableNamezh)             \
 261                                 SymI_HasProto(stg_finalizzeWeakzh)
 262
 263 #if !defined (mingw32_HOST_OS)
 264 #define RTS_POSIX_ONLY_SYMBOLS                  \
 265       SymI_HasProto(__hscore_get_saved_termios) \
 266       SymI_HasProto(__hscore_set_saved_termios) \
 267       SymI_HasProto(shutdownHaskellAndSignal)   \
 268       SymI_HasProto(lockFile)                   \
 269       SymI_HasProto(unlockFile)                 \
 270       SymI_HasProto(signal_handlers)            \
 271       SymI_HasProto(stg_sig_install)            \
 272       SymI_HasProto(rtsTimerSignal)             \
 273       SymI_NeedsProto(nocldstop)
 274 #endif
 275
 276 #if defined (cygwin32_HOST_OS)
 277 #define RTS_MINGW_ONLY_SYMBOLS /**/
 278 /* Don't have the ability to read import libs / archives, so
 279  * we have to stupidly list a lot of what libcygwin.a
 280  * exports; sigh.
 281  */
 282 #define RTS_CYGWIN_ONLY_SYMBOLS                          \
 283       SymI_HasProto(regfree)                             \
 284       SymI_HasProto(regexec)                             \
 285       SymI_HasProto(regerror)                            \
 286       SymI_HasProto(regcomp)                             \
 287       SymI_HasProto(__errno)                             \
 288       SymI_HasProto(access)                              \
 289       SymI_HasProto(chmod)                               \
 290       SymI_HasProto(chdir)                               \
 291       SymI_HasProto(close)                               \
 292       SymI_HasProto(creat)                               \
 293       SymI_HasProto(dup)                                 \
 294       SymI_HasProto(dup2)                                \
 295       SymI_HasProto(fstat)                               \
 296       SymI_HasProto(fcntl)                               \
 297       SymI_HasProto(getcwd)                              \
 298       SymI_HasProto(getenv)                              \
 299       SymI_HasProto(lseek)                               \
 300       SymI_HasProto(open)                                \
 301       SymI_HasProto(fpathconf)                           \
 302       SymI_HasProto(pathconf)                            \
 303       SymI_HasProto(stat)                                \
 304       SymI_HasProto(pow)                                 \
 305       SymI_HasProto(tanh)                                \
 306       SymI_HasProto(cosh)                                \
 307       SymI_HasProto(sinh)                                \
 308       SymI_HasProto(atan)                                \
 309       SymI_HasProto(acos)                                \
 310       SymI_HasProto(asin)                                \
 311       SymI_HasProto(tan)                                 \
 312       SymI_HasProto(cos)                                 \
 313       SymI_HasProto(sin)                                 \
 314       SymI_HasProto(exp)                                 \
 315       SymI_HasProto(log)                                 \
 316       SymI_HasProto(sqrt)                                \
 317       SymI_HasProto(localtime_r)                         \
 318       SymI_HasProto(gmtime_r)                            \
 319       SymI_HasProto(mktime)                              \
 320       SymI_NeedsProto(_imp___tzname)                     \
 321       SymI_HasProto(gettimeofday)                        \
 322       SymI_HasProto(timezone)                            \
 323       SymI_HasProto(tcgetattr)                           \
 324       SymI_HasProto(tcsetattr)                           \
 325       SymI_HasProto(memcpy)                              \
 326       SymI_HasProto(memmove)                             \
 327       SymI_HasProto(realloc)                             \
 328       SymI_HasProto(malloc)                              \
 329       SymI_HasProto(free)                                \
 330       SymI_HasProto(fork)                                \
 331       SymI_HasProto(lstat)                               \
 332       SymI_HasProto(isatty)                              \
 333       SymI_HasProto(mkdir)                               \
 334       SymI_HasProto(opendir)                             \
 335       SymI_HasProto(readdir)                             \
 336       SymI_HasProto(rewinddir)                           \
 337       SymI_HasProto(closedir)                            \
 338       SymI_HasProto(link)                                \
 339       SymI_HasProto(mkfifo)                              \
 340       SymI_HasProto(pipe)                                \
 341       SymI_HasProto(read)                                \
 342       SymI_HasProto(rename)                              \
 343       SymI_HasProto(rmdir)                               \
 344       SymI_HasProto(select)                              \
 345       SymI_HasProto(system)                              \
 346       SymI_HasProto(write)                               \
 347       SymI_HasProto(strcmp)                              \
 348       SymI_HasProto(strcpy)                              \
 349       SymI_HasProto(strncpy)                             \
 350       SymI_HasProto(strerror)                            \
 351       SymI_HasProto(sigaddset)                           \
 352       SymI_HasProto(sigemptyset)                         \
 353       SymI_HasProto(sigprocmask)                         \
 354       SymI_HasProto(umask)                               \
 355       SymI_HasProto(uname)                               \
 356       SymI_HasProto(unlink)                              \
 357       SymI_HasProto(utime)                               \
 358       SymI_HasProto(waitpid)
 359
 360 #elif !defined(mingw32_HOST_OS)
 361 #define RTS_MINGW_ONLY_SYMBOLS /**/
 362 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
 363 #else /* defined(mingw32_HOST_OS) */
 364 #define RTS_POSIX_ONLY_SYMBOLS  /**/
 365 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
 366
 367 #if HAVE_GETTIMEOFDAY
 368 #define RTS_MINGW_GETTIMEOFDAY_SYM SymI_NeedsProto(gettimeofday)
 369 #else
 370 #define RTS_MINGW_GETTIMEOFDAY_SYM /**/
 371 #endif
 372
 373 #if HAVE___MINGW_VFPRINTF
 374 #define RTS___MINGW_VFPRINTF_SYM SymI_HasProto(__mingw_vfprintf)
 375 #else
 376 #define RTS___MINGW_VFPRINTF_SYM /**/
 377 #endif
 378
 379 /* These are statically linked from the mingw libraries into the ghc
 380    executable, so we have to employ this hack. */
 381 #define RTS_MINGW_ONLY_SYMBOLS                           \
 382       SymI_HasProto(stg_asyncReadzh)                     \
 383       SymI_HasProto(stg_asyncWritezh)                    \
 384       SymI_HasProto(stg_asyncDoProczh)                   \
 385       SymI_HasProto(memset)                              \
 386       SymI_HasProto(inet_ntoa)                           \
 387       SymI_HasProto(inet_addr)                           \
 388       SymI_HasProto(htonl)                               \
 389       SymI_HasProto(recvfrom)                            \
 390       SymI_HasProto(listen)                              \
 391       SymI_HasProto(bind)                                \
 392       SymI_HasProto(shutdown)                            \
 393       SymI_HasProto(connect)                             \
 394       SymI_HasProto(htons)                               \
 395       SymI_HasProto(ntohs)                               \
 396       SymI_HasProto(getservbyname)                       \
 397       SymI_HasProto(getservbyport)                       \
 398       SymI_HasProto(getprotobynumber)                    \
 399       SymI_HasProto(getprotobyname)                      \
 400       SymI_HasProto(gethostbyname)                       \
 401       SymI_HasProto(gethostbyaddr)                       \
 402       SymI_HasProto(gethostname)                         \
 403       SymI_HasProto(strcpy)                              \
 404       SymI_HasProto(strncpy)                             \
 405       SymI_HasProto(abort)                               \
 406       SymI_NeedsProto(_alloca)                           \
 407       SymI_HasProto(isxdigit)                            \
 408       SymI_HasProto(isupper)                             \
 409       SymI_HasProto(ispunct)                             \
 410       SymI_HasProto(islower)                             \
 411       SymI_HasProto(isspace)                             \
 412       SymI_HasProto(isprint)                             \
 413       SymI_HasProto(isdigit)                             \
 414       SymI_HasProto(iscntrl)                             \
 415       SymI_HasProto(isalpha)                             \
 416       SymI_HasProto(isalnum)                             \
 417       SymI_HasProto(isascii)                             \
 418       RTS___MINGW_VFPRINTF_SYM                           \
 419       SymI_HasProto(strcmp)                              \
 420       SymI_HasProto(memmove)                             \
 421       SymI_HasProto(realloc)                             \
 422       SymI_HasProto(malloc)                              \
 423       SymI_HasProto(pow)                                 \
 424       SymI_HasProto(tanh)                                \
 425       SymI_HasProto(cosh)                                \
 426       SymI_HasProto(sinh)                                \
 427       SymI_HasProto(atan)                                \
 428       SymI_HasProto(acos)                                \
 429       SymI_HasProto(asin)                                \
 430       SymI_HasProto(tan)                                 \
 431       SymI_HasProto(cos)                                 \
 432       SymI_HasProto(sin)                                 \
 433       SymI_HasProto(exp)                                 \
 434       SymI_HasProto(log)                                 \
 435       SymI_HasProto(sqrt)                                \
 436       SymI_HasProto(powf)                                \
 437       SymI_HasProto(tanhf)                               \
 438       SymI_HasProto(coshf)                               \
 439       SymI_HasProto(sinhf)                               \
 440       SymI_HasProto(atanf)                               \
 441       SymI_HasProto(acosf)                               \
 442       SymI_HasProto(asinf)                               \
 443       SymI_HasProto(tanf)                                \
 444       SymI_HasProto(cosf)                                \
 445       SymI_HasProto(sinf)                                \
 446       SymI_HasProto(expf)                                \
 447       SymI_HasProto(logf)                                \
 448       SymI_HasProto(sqrtf)                               \
 449       SymI_HasProto(erf)                                 \
 450       SymI_HasProto(erfc)                                \
 451       SymI_HasProto(erff)                                \
 452       SymI_HasProto(erfcf)                               \
 453       SymI_HasProto(memcpy)                              \
 454       SymI_HasProto(rts_InstallConsoleEvent)             \
 455       SymI_HasProto(rts_ConsoleHandlerDone)              \
 456       SymI_NeedsProto(mktime)                            \
 457       SymI_NeedsProto(_imp___timezone)                   \
 458       SymI_NeedsProto(_imp___tzname)                     \
 459       SymI_NeedsProto(_imp__tzname)                      \
 460       SymI_NeedsProto(_imp___iob)                        \
 461       SymI_NeedsProto(_imp___osver)                      \
 462       SymI_NeedsProto(localtime)                         \
 463       SymI_NeedsProto(gmtime)                            \
 464       SymI_NeedsProto(opendir)                           \
 465       SymI_NeedsProto(readdir)                           \
 466       SymI_NeedsProto(rewinddir)                         \
 467       SymI_NeedsProto(_imp____mb_cur_max)                \
 468       SymI_NeedsProto(_imp___pctype)                     \
 469       SymI_NeedsProto(__chkstk)                          \
 470       RTS_MINGW_GETTIMEOFDAY_SYM                         \
 471       SymI_NeedsProto(closedir)
 472 #endif
 473
 474
 475 #if defined(darwin_HOST_OS) && HAVE_PRINTF_LDBLSTUB
 476 #define RTS_DARWIN_ONLY_SYMBOLS                             \
 477      SymI_NeedsProto(asprintf$LDBLStub)                     \
 478      SymI_NeedsProto(err$LDBLStub)                          \
 479      SymI_NeedsProto(errc$LDBLStub)                         \
 480      SymI_NeedsProto(errx$LDBLStub)                         \
 481      SymI_NeedsProto(fprintf$LDBLStub)                      \
 482      SymI_NeedsProto(fscanf$LDBLStub)                       \
 483      SymI_NeedsProto(fwprintf$LDBLStub)                     \
 484      SymI_NeedsProto(fwscanf$LDBLStub)                      \
 485      SymI_NeedsProto(printf$LDBLStub)                       \
 486      SymI_NeedsProto(scanf$LDBLStub)                        \
 487      SymI_NeedsProto(snprintf$LDBLStub)                     \
 488      SymI_NeedsProto(sprintf$LDBLStub)                      \
 489      SymI_NeedsProto(sscanf$LDBLStub)                       \
 490      SymI_NeedsProto(strtold$LDBLStub)                      \
 491      SymI_NeedsProto(swprintf$LDBLStub)                     \
 492      SymI_NeedsProto(swscanf$LDBLStub)                      \
 493      SymI_NeedsProto(syslog$LDBLStub)                       \
 494      SymI_NeedsProto(vasprintf$LDBLStub)                    \
 495      SymI_NeedsProto(verr$LDBLStub)                         \
 496      SymI_NeedsProto(verrc$LDBLStub)                        \
 497      SymI_NeedsProto(verrx$LDBLStub)                        \
 498      SymI_NeedsProto(vfprintf$LDBLStub)                     \
 499      SymI_NeedsProto(vfscanf$LDBLStub)                      \
 500      SymI_NeedsProto(vfwprintf$LDBLStub)                    \
 501      SymI_NeedsProto(vfwscanf$LDBLStub)                     \
 502      SymI_NeedsProto(vprintf$LDBLStub)                      \
 503      SymI_NeedsProto(vscanf$LDBLStub)                       \
 504      SymI_NeedsProto(vsnprintf$LDBLStub)                    \
 505      SymI_NeedsProto(vsprintf$LDBLStub)                     \
 506      SymI_NeedsProto(vsscanf$LDBLStub)                      \
 507      SymI_NeedsProto(vswprintf$LDBLStub)                    \
 508      SymI_NeedsProto(vswscanf$LDBLStub)                     \
 509      SymI_NeedsProto(vsyslog$LDBLStub)                      \
 510      SymI_NeedsProto(vwarn$LDBLStub)                        \
 511      SymI_NeedsProto(vwarnc$LDBLStub)                       \
 512      SymI_NeedsProto(vwarnx$LDBLStub)                       \
 513      SymI_NeedsProto(vwprintf$LDBLStub)                     \
 514      SymI_NeedsProto(vwscanf$LDBLStub)                      \
 515      SymI_NeedsProto(warn$LDBLStub)                         \
 516      SymI_NeedsProto(warnc$LDBLStub)                        \
 517      SymI_NeedsProto(warnx$LDBLStub)                        \
 518      SymI_NeedsProto(wcstold$LDBLStub)                      \
 519      SymI_NeedsProto(wprintf$LDBLStub)                      \
 520      SymI_NeedsProto(wscanf$LDBLStub)
 521 #else
 522 #define RTS_DARWIN_ONLY_SYMBOLS
 523 #endif
 524
 525 #ifndef SMP
 526 # define MAIN_CAP_SYM SymI_HasProto(MainCapability)
 527 #else
 528 # define MAIN_CAP_SYM
 529 #endif
 530
 531 #if !defined(mingw32_HOST_OS)
 532 #define RTS_USER_SIGNALS_SYMBOLS        \
 533    SymI_HasProto(setIOManagerControlFd) \
 534    SymI_HasProto(setIOManagerWakeupFd)  \
 535    SymI_HasProto(ioManagerWakeup)       \
 536    SymI_HasProto(blockUserSignals)      \
 537    SymI_HasProto(unblockUserSignals)
 538 #else
 539 #define RTS_USER_SIGNALS_SYMBOLS        \
 540    SymI_HasProto(ioManagerWakeup)       \
 541    SymI_HasProto(sendIOManagerEvent)    \
 542    SymI_HasProto(readIOManagerEvent)    \
 543    SymI_HasProto(getIOManagerEvent)     \
 544    SymI_HasProto(console_handler)
 545 #endif
 546
 547 #define RTS_LIBFFI_SYMBOLS                                  \
 548      SymE_NeedsProto(ffi_prep_cif)                          \
 549      SymE_NeedsProto(ffi_call)                              \
 550      SymE_NeedsProto(ffi_type_void)                         \
 551      SymE_NeedsProto(ffi_type_float)                        \
 552      SymE_NeedsProto(ffi_type_double)                       \
 553      SymE_NeedsProto(ffi_type_sint64)                       \
 554      SymE_NeedsProto(ffi_type_uint64)                       \
 555      SymE_NeedsProto(ffi_type_sint32)                       \
 556      SymE_NeedsProto(ffi_type_uint32)                       \
 557      SymE_NeedsProto(ffi_type_sint16)                       \
 558      SymE_NeedsProto(ffi_type_uint16)                       \
 559      SymE_NeedsProto(ffi_type_sint8)                        \
 560      SymE_NeedsProto(ffi_type_uint8)                        \
 561      SymE_NeedsProto(ffi_type_pointer)
 562
 563 #ifdef TABLES_NEXT_TO_CODE
 564 #define RTS_RET_SYMBOLS /* nothing */
 565 #else
 566 #define RTS_RET_SYMBOLS                                 \
 567       SymI_HasProto(stg_enter_ret)                      \
 568       SymI_HasProto(stg_gc_fun_ret)                     \
 569       SymI_HasProto(stg_ap_v_ret)                       \
 570       SymI_HasProto(stg_ap_f_ret)                       \
 571       SymI_HasProto(stg_ap_d_ret)                       \
 572       SymI_HasProto(stg_ap_l_ret)                       \
 573       SymI_HasProto(stg_ap_n_ret)                       \
 574       SymI_HasProto(stg_ap_p_ret)                       \
 575       SymI_HasProto(stg_ap_pv_ret)                      \
 576       SymI_HasProto(stg_ap_pp_ret)                      \
 577       SymI_HasProto(stg_ap_ppv_ret)                     \
 578       SymI_HasProto(stg_ap_ppp_ret)                     \
 579       SymI_HasProto(stg_ap_pppv_ret)                    \
 580       SymI_HasProto(stg_ap_pppp_ret)                    \
 581       SymI_HasProto(stg_ap_ppppp_ret)                   \
 582       SymI_HasProto(stg_ap_pppppp_ret)
 583 #endif
 584
 585 /* Modules compiled with -ticky may mention ticky counters */
 586 /* This list should marry up with the one in $(TOP)/includes/stg/Ticky.h */
 587 #define RTS_TICKY_SYMBOLS                               \
 588       SymI_NeedsProto(ticky_entry_ctrs)                 \
 589       SymI_NeedsProto(top_ct)                           \
 590                                                         \
 591       SymI_HasProto(ENT_VIA_NODE_ctr)                   \
 592       SymI_HasProto(ENT_STATIC_THK_ctr)                 \
 593       SymI_HasProto(ENT_DYN_THK_ctr)                    \
 594       SymI_HasProto(ENT_STATIC_FUN_DIRECT_ctr)          \
 595       SymI_HasProto(ENT_DYN_FUN_DIRECT_ctr)             \
 596       SymI_HasProto(ENT_STATIC_CON_ctr)                 \
 597       SymI_HasProto(ENT_DYN_CON_ctr)                    \
 598       SymI_HasProto(ENT_STATIC_IND_ctr)                 \
 599       SymI_HasProto(ENT_DYN_IND_ctr)                    \
 600       SymI_HasProto(ENT_PERM_IND_ctr)                   \
 601       SymI_HasProto(ENT_PAP_ctr)                        \
 602       SymI_HasProto(ENT_AP_ctr)                         \
 603       SymI_HasProto(ENT_AP_STACK_ctr)                   \
 604       SymI_HasProto(ENT_BH_ctr)                         \
 605       SymI_HasProto(UNKNOWN_CALL_ctr)                   \
 606       SymI_HasProto(SLOW_CALL_v_ctr)                    \
 607       SymI_HasProto(SLOW_CALL_f_ctr)                    \
 608       SymI_HasProto(SLOW_CALL_d_ctr)                    \
 609       SymI_HasProto(SLOW_CALL_l_ctr)                    \
 610       SymI_HasProto(SLOW_CALL_n_ctr)                    \
 611       SymI_HasProto(SLOW_CALL_p_ctr)                    \
 612       SymI_HasProto(SLOW_CALL_pv_ctr)                   \
 613       SymI_HasProto(SLOW_CALL_pp_ctr)                   \
 614       SymI_HasProto(SLOW_CALL_ppv_ctr)                  \
 615       SymI_HasProto(SLOW_CALL_ppp_ctr)                  \
 616       SymI_HasProto(SLOW_CALL_pppv_ctr)                 \
 617       SymI_HasProto(SLOW_CALL_pppp_ctr)                 \
 618       SymI_HasProto(SLOW_CALL_ppppp_ctr)                \
 619       SymI_HasProto(SLOW_CALL_pppppp_ctr)               \
 620       SymI_HasProto(SLOW_CALL_OTHER_ctr)                \
 621       SymI_HasProto(ticky_slow_call_unevald)            \
 622       SymI_HasProto(SLOW_CALL_ctr)                      \
 623       SymI_HasProto(MULTI_CHUNK_SLOW_CALL_ctr)          \
 624       SymI_HasProto(MULTI_CHUNK_SLOW_CALL_CHUNKS_ctr)   \
 625       SymI_HasProto(KNOWN_CALL_ctr)                     \
 626       SymI_HasProto(KNOWN_CALL_TOO_FEW_ARGS_ctr)        \
 627       SymI_HasProto(KNOWN_CALL_EXTRA_ARGS_ctr)          \
 628       SymI_HasProto(SLOW_CALL_FUN_TOO_FEW_ctr)          \
 629       SymI_HasProto(SLOW_CALL_FUN_CORRECT_ctr)          \
 630       SymI_HasProto(SLOW_CALL_FUN_TOO_MANY_ctr)         \
 631       SymI_HasProto(SLOW_CALL_PAP_TOO_FEW_ctr)          \
 632       SymI_HasProto(SLOW_CALL_PAP_CORRECT_ctr)          \
 633       SymI_HasProto(SLOW_CALL_PAP_TOO_MANY_ctr)         \
 634       SymI_HasProto(SLOW_CALL_UNEVALD_ctr)              \
 635       SymI_HasProto(UPDF_OMITTED_ctr)                   \
 636       SymI_HasProto(UPDF_PUSHED_ctr)                    \
 637       SymI_HasProto(CATCHF_PUSHED_ctr)                  \
 638       SymI_HasProto(UPDF_RCC_PUSHED_ctr)                \
 639       SymI_HasProto(UPDF_RCC_OMITTED_ctr)               \
 640       SymI_HasProto(UPD_SQUEEZED_ctr)                   \
 641       SymI_HasProto(UPD_CON_IN_NEW_ctr)                 \
 642       SymI_HasProto(UPD_CON_IN_PLACE_ctr)               \
 643       SymI_HasProto(UPD_PAP_IN_NEW_ctr)                 \
 644       SymI_HasProto(UPD_PAP_IN_PLACE_ctr)               \
 645       SymI_HasProto(ALLOC_HEAP_ctr)                     \
 646       SymI_HasProto(ALLOC_HEAP_tot)                     \
 647       SymI_HasProto(ALLOC_FUN_ctr)                      \
 648       SymI_HasProto(ALLOC_FUN_adm)                      \
 649       SymI_HasProto(ALLOC_FUN_gds)                      \
 650       SymI_HasProto(ALLOC_FUN_slp)                      \
 651       SymI_HasProto(UPD_NEW_IND_ctr)                    \
 652       SymI_HasProto(UPD_NEW_PERM_IND_ctr)               \
 653       SymI_HasProto(UPD_OLD_IND_ctr)                    \
 654       SymI_HasProto(UPD_OLD_PERM_IND_ctr)               \
 655       SymI_HasProto(UPD_BH_UPDATABLE_ctr)               \
 656       SymI_HasProto(UPD_BH_SINGLE_ENTRY_ctr)            \
 657       SymI_HasProto(UPD_CAF_BH_UPDATABLE_ctr)           \
 658       SymI_HasProto(UPD_CAF_BH_SINGLE_ENTRY_ctr)        \
 659       SymI_HasProto(GC_SEL_ABANDONED_ctr)               \
 660       SymI_HasProto(GC_SEL_MINOR_ctr)                   \
 661       SymI_HasProto(GC_SEL_MAJOR_ctr)                   \
 662       SymI_HasProto(GC_FAILED_PROMOTION_ctr)            \
 663       SymI_HasProto(ALLOC_UP_THK_ctr)                   \
 664       SymI_HasProto(ALLOC_SE_THK_ctr)                   \
 665       SymI_HasProto(ALLOC_THK_adm)                      \
 666       SymI_HasProto(ALLOC_THK_gds)                      \
 667       SymI_HasProto(ALLOC_THK_slp)                      \
 668       SymI_HasProto(ALLOC_CON_ctr)                      \
 669       SymI_HasProto(ALLOC_CON_adm)                      \
 670       SymI_HasProto(ALLOC_CON_gds)                      \
 671       SymI_HasProto(ALLOC_CON_slp)                      \
 672       SymI_HasProto(ALLOC_TUP_ctr)                      \
 673       SymI_HasProto(ALLOC_TUP_adm)                      \
 674       SymI_HasProto(ALLOC_TUP_gds)                      \
 675       SymI_HasProto(ALLOC_TUP_slp)                      \
 676       SymI_HasProto(ALLOC_BH_ctr)                       \
 677       SymI_HasProto(ALLOC_BH_adm)                       \
 678       SymI_HasProto(ALLOC_BH_gds)                       \
 679       SymI_HasProto(ALLOC_BH_slp)                       \
 680       SymI_HasProto(ALLOC_PRIM_ctr)                     \
 681       SymI_HasProto(ALLOC_PRIM_adm)                     \
 682       SymI_HasProto(ALLOC_PRIM_gds)                     \
 683       SymI_HasProto(ALLOC_PRIM_slp)                     \
 684       SymI_HasProto(ALLOC_PAP_ctr)                      \
 685       SymI_HasProto(ALLOC_PAP_adm)                      \
 686       SymI_HasProto(ALLOC_PAP_gds)                      \
 687       SymI_HasProto(ALLOC_PAP_slp)                      \
 688       SymI_HasProto(ALLOC_TSO_ctr)                      \
 689       SymI_HasProto(ALLOC_TSO_adm)                      \
 690       SymI_HasProto(ALLOC_TSO_gds)                      \
 691       SymI_HasProto(ALLOC_TSO_slp)                      \
 692       SymI_HasProto(RET_NEW_ctr)                        \
 693       SymI_HasProto(RET_OLD_ctr)                        \
 694       SymI_HasProto(RET_UNBOXED_TUP_ctr)                \
 695       SymI_HasProto(RET_SEMI_loads_avoided)
 696
 697
 698 // On most platforms, the garbage collector rewrites references
 699 //      to small integer and char objects to a set of common, shared ones.
 700 //
 701 // We don't do this when compiling to Windows DLLs at the moment because
 702 //      it doesn't support cross package data references well.
 703 //
 704 #if defined(__PIC__) && defined(mingw32_HOST_OS)
 705 #define RTS_INTCHAR_SYMBOLS
 706 #else
 707 #define RTS_INTCHAR_SYMBOLS                             \
 708       SymI_HasProto(stg_CHARLIKE_closure)               \
 709       SymI_HasProto(stg_INTLIKE_closure)
 710 #endif
 711
 712
 713 #define RTS_SYMBOLS                                     \
 714       Maybe_Stable_Names                                \
 715       RTS_TICKY_SYMBOLS                                 \
 716       SymI_HasProto(StgReturn)                          \
 717       SymI_HasProto(stg_enter_info)                     \
 718       SymI_HasProto(stg_gc_void_info)                   \
 719       SymI_HasProto(__stg_gc_enter_1)                   \
 720       SymI_HasProto(stg_gc_noregs)                      \
 721       SymI_HasProto(stg_gc_unpt_r1_info)                \
 722       SymI_HasProto(stg_gc_unpt_r1)                     \
 723       SymI_HasProto(stg_gc_unbx_r1_info)                \
 724       SymI_HasProto(stg_gc_unbx_r1)                     \
 725       SymI_HasProto(stg_gc_f1_info)                     \
 726       SymI_HasProto(stg_gc_f1)                          \
 727       SymI_HasProto(stg_gc_d1_info)                     \
 728       SymI_HasProto(stg_gc_d1)                          \
 729       SymI_HasProto(stg_gc_l1_info)                     \
 730       SymI_HasProto(stg_gc_l1)                          \
 731       SymI_HasProto(__stg_gc_fun)                       \
 732       SymI_HasProto(stg_gc_fun_info)                    \
 733       SymI_HasProto(stg_gc_gen)                         \
 734       SymI_HasProto(stg_gc_gen_info)                    \
 735       SymI_HasProto(stg_gc_gen_hp)                      \
 736       SymI_HasProto(stg_gc_ut)                          \
 737       SymI_HasProto(stg_gen_yield)                      \
 738       SymI_HasProto(stg_yield_noregs)                   \
 739       SymI_HasProto(stg_yield_to_interpreter)           \
 740       SymI_HasProto(stg_gen_block)                      \
 741       SymI_HasProto(stg_block_noregs)                   \
 742       SymI_HasProto(stg_block_1)                        \
 743       SymI_HasProto(stg_block_takemvar)                 \
 744       SymI_HasProto(stg_block_putmvar)                  \
 745       MAIN_CAP_SYM                                      \
 746       SymI_HasProto(MallocFailHook)                     \
 747       SymI_HasProto(OnExitHook)                         \
 748       SymI_HasProto(OutOfHeapHook)                      \
 749       SymI_HasProto(StackOverflowHook)                  \
 750       SymI_HasProto(addDLL)                             \
 751       SymI_HasProto(__int_encodeDouble)                 \
 752       SymI_HasProto(__word_encodeDouble)                \
 753       SymI_HasProto(__2Int_encodeDouble)                \
 754       SymI_HasProto(__int_encodeFloat)                  \
 755       SymI_HasProto(__word_encodeFloat)                 \
 756       SymI_HasProto(stg_atomicallyzh)                   \
 757       SymI_HasProto(barf)                               \
 758       SymI_HasProto(debugBelch)                         \
 759       SymI_HasProto(errorBelch)                         \
 760       SymI_HasProto(sysErrorBelch)                      \
 761       SymI_HasProto(stg_getMaskingStatezh)              \
 762       SymI_HasProto(stg_maskAsyncExceptionszh)          \
 763       SymI_HasProto(stg_maskUninterruptiblezh)          \
 764       SymI_HasProto(stg_catchzh)                        \
 765       SymI_HasProto(stg_catchRetryzh)                   \
 766       SymI_HasProto(stg_catchSTMzh)                     \
 767       SymI_HasProto(stg_checkzh)                        \
 768       SymI_HasProto(closure_flags)                      \
 769       SymI_HasProto(cmp_thread)                         \
 770       SymI_HasProto(createAdjustor)                     \
 771       SymI_HasProto(stg_decodeDoublezu2Intzh)           \
 772       SymI_HasProto(stg_decodeFloatzuIntzh)             \
 773       SymI_HasProto(defaultsHook)                       \
 774       SymI_HasProto(stg_delayzh)                        \
 775       SymI_HasProto(stg_deRefWeakzh)                    \
 776       SymI_HasProto(stg_deRefStablePtrzh)               \
 777       SymI_HasProto(dirty_MUT_VAR)                      \
 778       SymI_HasProto(stg_forkzh)                         \
 779       SymI_HasProto(stg_forkOnzh)                       \
 780       SymI_HasProto(forkProcess)                        \
 781       SymI_HasProto(forkOS_createThread)                \
 782       SymI_HasProto(freeHaskellFunctionPtr)             \
 783       SymI_HasProto(getOrSetTypeableStore)              \
 784       SymI_HasProto(getOrSetGHCConcSignalSignalHandlerStore)            \
 785       SymI_HasProto(getOrSetGHCConcWindowsPendingDelaysStore)           \
 786       SymI_HasProto(getOrSetGHCConcWindowsIOManagerThreadStore)         \
 787       SymI_HasProto(getOrSetGHCConcWindowsProddingStore)                \
 788       SymI_HasProto(getOrSetSystemEventThreadEventManagerStore)         \
 789       SymI_HasProto(getOrSetSystemEventThreadIOManagerThreadStore)      \
 790       SymI_HasProto(genSymZh)                           \
 791       SymI_HasProto(genericRaise)                       \
 792       SymI_HasProto(getProgArgv)                        \
 793       SymI_HasProto(getFullProgArgv)                    \
 794       SymI_HasProto(getStablePtr)                       \
 795       SymI_HasProto(hs_init)                            \
 796       SymI_HasProto(hs_exit)                            \
 797       SymI_HasProto(hs_set_argv)                        \
 798       SymI_HasProto(hs_add_root)                        \
 799       SymI_HasProto(hs_perform_gc)                      \
 800       SymI_HasProto(hs_free_stable_ptr)                 \
 801       SymI_HasProto(hs_free_fun_ptr)                    \
 802       SymI_HasProto(hs_hpc_rootModule)                  \
 803       SymI_HasProto(hs_hpc_module)                      \
 804       SymI_HasProto(initLinker)                         \
 805       SymI_HasProto(stg_unpackClosurezh)                \
 806       SymI_HasProto(stg_getApStackValzh)                \
 807       SymI_HasProto(stg_getSparkzh)                     \
 808       SymI_HasProto(stg_numSparkszh)                    \
 809       SymI_HasProto(stg_isCurrentThreadBoundzh)         \
 810       SymI_HasProto(stg_isEmptyMVarzh)                  \
 811       SymI_HasProto(stg_killThreadzh)                   \
 812       SymI_HasProto(loadArchive)                        \
 813       SymI_HasProto(loadObj)                            \
 814       SymI_HasProto(insertStableSymbol)                 \
 815       SymI_HasProto(insertSymbol)                       \
 816       SymI_HasProto(lookupSymbol)                       \
 817       SymI_HasProto(stg_makeStablePtrzh)                \
 818       SymI_HasProto(stg_mkApUpd0zh)                     \
 819       SymI_HasProto(stg_myThreadIdzh)                   \
 820       SymI_HasProto(stg_labelThreadzh)                  \
 821       SymI_HasProto(stg_newArrayzh)                     \
 822       SymI_HasProto(stg_newBCOzh)                       \
 823       SymI_HasProto(stg_newByteArrayzh)                 \
 824       SymI_HasProto_redirect(newCAF, newDynCAF)         \
 825       SymI_HasProto(stg_newMVarzh)                      \
 826       SymI_HasProto(stg_newMutVarzh)                    \
 827       SymI_HasProto(stg_newTVarzh)                      \
 828       SymI_HasProto(stg_noDuplicatezh)                  \
 829       SymI_HasProto(stg_atomicModifyMutVarzh)           \
 830       SymI_HasProto(stg_newPinnedByteArrayzh)           \
 831       SymI_HasProto(stg_newAlignedPinnedByteArrayzh)    \
 832       SymI_HasProto(newSpark)                           \
 833       SymI_HasProto(performGC)                          \
 834       SymI_HasProto(performMajorGC)                     \
 835       SymI_HasProto(prog_argc)                          \
 836       SymI_HasProto(prog_argv)                          \
 837       SymI_HasProto(stg_putMVarzh)                      \
 838       SymI_HasProto(stg_raisezh)                        \
 839       SymI_HasProto(stg_raiseIOzh)                      \
 840       SymI_HasProto(stg_readTVarzh)                     \
 841       SymI_HasProto(stg_readTVarIOzh)                   \
 842       SymI_HasProto(resumeThread)                       \
 843       SymI_HasProto(resolveObjs)                        \
 844       SymI_HasProto(stg_retryzh)                        \
 845       SymI_HasProto(rts_apply)                          \
 846       SymI_HasProto(rts_checkSchedStatus)               \
 847       SymI_HasProto(rts_eval)                           \
 848       SymI_HasProto(rts_evalIO)                         \
 849       SymI_HasProto(rts_evalLazyIO)                     \
 850       SymI_HasProto(rts_evalStableIO)                   \
 851       SymI_HasProto(rts_eval_)                          \
 852       SymI_HasProto(rts_getBool)                        \
 853       SymI_HasProto(rts_getChar)                        \
 854       SymI_HasProto(rts_getDouble)                      \
 855       SymI_HasProto(rts_getFloat)                       \
 856       SymI_HasProto(rts_getInt)                         \
 857       SymI_HasProto(rts_getInt8)                        \
 858       SymI_HasProto(rts_getInt16)                       \
 859       SymI_HasProto(rts_getInt32)                       \
 860       SymI_HasProto(rts_getInt64)                       \
 861       SymI_HasProto(rts_getPtr)                         \
 862       SymI_HasProto(rts_getFunPtr)                      \
 863       SymI_HasProto(rts_getStablePtr)                   \
 864       SymI_HasProto(rts_getThreadId)                    \
 865       SymI_HasProto(rts_getWord)                        \
 866       SymI_HasProto(rts_getWord8)                       \
 867       SymI_HasProto(rts_getWord16)                      \
 868       SymI_HasProto(rts_getWord32)                      \
 869       SymI_HasProto(rts_getWord64)                      \
 870       SymI_HasProto(rts_lock)                           \
 871       SymI_HasProto(rts_mkBool)                         \
 872       SymI_HasProto(rts_mkChar)                         \
 873       SymI_HasProto(rts_mkDouble)                       \
 874       SymI_HasProto(rts_mkFloat)                        \
 875       SymI_HasProto(rts_mkInt)                          \
 876       SymI_HasProto(rts_mkInt8)                         \
 877       SymI_HasProto(rts_mkInt16)                        \
 878       SymI_HasProto(rts_mkInt32)                        \
 879       SymI_HasProto(rts_mkInt64)                        \
 880       SymI_HasProto(rts_mkPtr)                          \
 881       SymI_HasProto(rts_mkFunPtr)                       \
 882       SymI_HasProto(rts_mkStablePtr)                    \
 883       SymI_HasProto(rts_mkString)                       \
 884       SymI_HasProto(rts_mkWord)                         \
 885       SymI_HasProto(rts_mkWord8)                        \
 886       SymI_HasProto(rts_mkWord16)                       \
 887       SymI_HasProto(rts_mkWord32)                       \
 888       SymI_HasProto(rts_mkWord64)                       \
 889       SymI_HasProto(rts_unlock)                         \
 890       SymI_HasProto(rts_unsafeGetMyCapability)          \
 891       SymI_HasProto(rtsSupportsBoundThreads)            \
 892       SymI_HasProto(rts_isProfiled)                     \
 893       SymI_HasProto(setProgArgv)                        \
 894       SymI_HasProto(startupHaskell)                     \
 895       SymI_HasProto(shutdownHaskell)                    \
 896       SymI_HasProto(shutdownHaskellAndExit)             \
 897       SymI_HasProto(stable_ptr_table)                   \
 898       SymI_HasProto(stackOverflow)                      \
 899       SymI_HasProto(stg_CAF_BLACKHOLE_info)             \
 900       SymI_HasProto(stg_BLACKHOLE_info)                 \
 901       SymI_HasProto(__stg_EAGER_BLACKHOLE_info)         \
 902       SymI_HasProto(stg_BLOCKING_QUEUE_CLEAN_info)      \
 903       SymI_HasProto(stg_BLOCKING_QUEUE_DIRTY_info)      \
 904       SymI_HasProto(startTimer)                         \
 905       SymI_HasProto(stg_MVAR_CLEAN_info)                \
 906       SymI_HasProto(stg_MVAR_DIRTY_info)                \
 907       SymI_HasProto(stg_IND_STATIC_info)                \
 908       SymI_HasProto(stg_ARR_WORDS_info)                 \
 909       SymI_HasProto(stg_MUT_ARR_PTRS_DIRTY_info)        \
 910       SymI_HasProto(stg_MUT_ARR_PTRS_FROZEN_info)       \
 911       SymI_HasProto(stg_MUT_ARR_PTRS_FROZEN0_info)      \
 912       SymI_HasProto(stg_WEAK_info)                      \
 913       SymI_HasProto(stg_ap_v_info)                      \
 914       SymI_HasProto(stg_ap_f_info)                      \
 915       SymI_HasProto(stg_ap_d_info)                      \
 916       SymI_HasProto(stg_ap_l_info)                      \
 917       SymI_HasProto(stg_ap_n_info)                      \
 918       SymI_HasProto(stg_ap_p_info)                      \
 919       SymI_HasProto(stg_ap_pv_info)                     \
 920       SymI_HasProto(stg_ap_pp_info)                     \
 921       SymI_HasProto(stg_ap_ppv_info)                    \
 922       SymI_HasProto(stg_ap_ppp_info)                    \
 923       SymI_HasProto(stg_ap_pppv_info)                   \
 924       SymI_HasProto(stg_ap_pppp_info)                   \
 925       SymI_HasProto(stg_ap_ppppp_info)                  \
 926       SymI_HasProto(stg_ap_pppppp_info)                 \
 927       SymI_HasProto(stg_ap_0_fast)                      \
 928       SymI_HasProto(stg_ap_v_fast)                      \
 929       SymI_HasProto(stg_ap_f_fast)                      \
 930       SymI_HasProto(stg_ap_d_fast)                      \
 931       SymI_HasProto(stg_ap_l_fast)                      \
 932       SymI_HasProto(stg_ap_n_fast)                      \
 933       SymI_HasProto(stg_ap_p_fast)                      \
 934       SymI_HasProto(stg_ap_pv_fast)                     \
 935       SymI_HasProto(stg_ap_pp_fast)                     \
 936       SymI_HasProto(stg_ap_ppv_fast)                    \
 937       SymI_HasProto(stg_ap_ppp_fast)                    \
 938       SymI_HasProto(stg_ap_pppv_fast)                   \
 939       SymI_HasProto(stg_ap_pppp_fast)                   \
 940       SymI_HasProto(stg_ap_ppppp_fast)                  \
 941       SymI_HasProto(stg_ap_pppppp_fast)                 \
 942       SymI_HasProto(stg_ap_1_upd_info)                  \
 943       SymI_HasProto(stg_ap_2_upd_info)                  \
 944       SymI_HasProto(stg_ap_3_upd_info)                  \
 945       SymI_HasProto(stg_ap_4_upd_info)                  \
 946       SymI_HasProto(stg_ap_5_upd_info)                  \
 947       SymI_HasProto(stg_ap_6_upd_info)                  \
 948       SymI_HasProto(stg_ap_7_upd_info)                  \
 949       SymI_HasProto(stg_exit)                           \
 950       SymI_HasProto(stg_sel_0_upd_info)                 \
 951       SymI_HasProto(stg_sel_10_upd_info)                \
 952       SymI_HasProto(stg_sel_11_upd_info)                \
 953       SymI_HasProto(stg_sel_12_upd_info)                \
 954       SymI_HasProto(stg_sel_13_upd_info)                \
 955       SymI_HasProto(stg_sel_14_upd_info)                \
 956       SymI_HasProto(stg_sel_15_upd_info)                \
 957       SymI_HasProto(stg_sel_1_upd_info)                 \
 958       SymI_HasProto(stg_sel_2_upd_info)                 \
 959       SymI_HasProto(stg_sel_3_upd_info)                 \
 960       SymI_HasProto(stg_sel_4_upd_info)                 \
 961       SymI_HasProto(stg_sel_5_upd_info)                 \
 962       SymI_HasProto(stg_sel_6_upd_info)                 \
 963       SymI_HasProto(stg_sel_7_upd_info)                 \
 964       SymI_HasProto(stg_sel_8_upd_info)                 \
 965       SymI_HasProto(stg_sel_9_upd_info)                 \
 966       SymI_HasProto(stg_upd_frame_info)                 \
 967       SymI_HasProto(stg_bh_upd_frame_info)              \
 968       SymI_HasProto(suspendThread)                      \
 969       SymI_HasProto(stg_takeMVarzh)                     \
 970       SymI_HasProto(stg_threadStatuszh)                 \
 971       SymI_HasProto(stg_tryPutMVarzh)                   \
 972       SymI_HasProto(stg_tryTakeMVarzh)                  \
 973       SymI_HasProto(stg_unmaskAsyncExceptionszh)        \
 974       SymI_HasProto(unloadObj)                          \
 975       SymI_HasProto(stg_unsafeThawArrayzh)              \
 976       SymI_HasProto(stg_waitReadzh)                     \
 977       SymI_HasProto(stg_waitWritezh)                    \
 978       SymI_HasProto(stg_writeTVarzh)                    \
 979       SymI_HasProto(stg_yieldzh)                        \
 980       SymI_NeedsProto(stg_interp_constr_entry)          \
 981       SymI_HasProto(stg_arg_bitmaps)                    \
 982       SymI_HasProto(large_alloc_lim)                    \
 983       SymI_HasProto(g0)                                 \
 984       SymI_HasProto(allocate)                           \
 985       SymI_HasProto(allocateExec)                       \
 986       SymI_HasProto(freeExec)                           \
 987       SymI_HasProto(getAllocations)                     \
 988       SymI_HasProto(revertCAFs)                         \
 989       SymI_HasProto(RtsFlags)                           \
 990       SymI_NeedsProto(rts_breakpoint_io_action)         \
 991       SymI_NeedsProto(rts_stop_next_breakpoint)         \
 992       SymI_NeedsProto(rts_stop_on_exception)            \
 993       SymI_HasProto(stopTimer)                          \
 994       SymI_HasProto(n_capabilities)                     \
 995       SymI_HasProto(stg_traceCcszh)                     \
 996       SymI_HasProto(stg_traceEventzh)                   \
 997       RTS_USER_SIGNALS_SYMBOLS                          \
 998       RTS_INTCHAR_SYMBOLS
 999
1000
1001 // 64-bit support functions in libgcc.a
1002 #if defined(__GNUC__) && SIZEOF_VOID_P <= 4
1003 #define RTS_LIBGCC_SYMBOLS                             \
1004       SymI_NeedsProto(__divdi3)                        \
1005       SymI_NeedsProto(__udivdi3)                       \
1006       SymI_NeedsProto(__moddi3)                        \
1007       SymI_NeedsProto(__umoddi3)                       \
1008       SymI_NeedsProto(__muldi3)                        \
1009       SymI_NeedsProto(__ashldi3)                       \
1010       SymI_NeedsProto(__ashrdi3)                       \
1011       SymI_NeedsProto(__lshrdi3)
1012 #else
1013 #define RTS_LIBGCC_SYMBOLS
1014 #endif
1015
1016 #if defined(darwin_HOST_OS) && defined(powerpc_HOST_ARCH)
1017       // Symbols that don't have a leading underscore
1018       // on Mac OS X. They have to receive special treatment,
1019       // see machoInitSymbolsWithoutUnderscore()
1020 #define RTS_MACHO_NOUNDERLINE_SYMBOLS                   \
1021       SymI_NeedsProto(saveFP)                           \
1022       SymI_NeedsProto(restFP)
1023 #endif
1024
1025 /* entirely bogus claims about types of these symbols */
1026 #define SymI_NeedsProto(vvv)  extern void vvv(void);
1027 #if defined(__PIC__) && defined(mingw32_HOST_OS)
1028 #define SymE_HasProto(vvv)    SymE_HasProto(vvv);
1029 #define SymE_NeedsProto(vvv)    extern void _imp__ ## vvv (void);
1030 #else
1031 #define SymE_NeedsProto(vvv)  SymI_NeedsProto(vvv);
1032 #define SymE_HasProto(vvv)    SymI_HasProto(vvv)
1033 #endif
1034 #define SymI_HasProto(vvv) /**/
1035 #define SymI_HasProto_redirect(vvv,xxx) /**/
1036 RTS_SYMBOLS
1037 RTS_RET_SYMBOLS
1038 RTS_POSIX_ONLY_SYMBOLS
1039 RTS_MINGW_ONLY_SYMBOLS
1040 RTS_CYGWIN_ONLY_SYMBOLS
1041 RTS_DARWIN_ONLY_SYMBOLS
1042 RTS_LIBGCC_SYMBOLS
1043 RTS_LIBFFI_SYMBOLS
1044 #undef SymI_NeedsProto
1045 #undef SymI_HasProto
1046 #undef SymI_HasProto_redirect
1047 #undef SymE_HasProto
1048 #undef SymE_NeedsProto
1049
1050 #ifdef LEADING_UNDERSCORE
1051 #define MAYBE_LEADING_UNDERSCORE_STR(s) ("_" s)
1052 #else
1053 #define MAYBE_LEADING_UNDERSCORE_STR(s) (s)
1054 #endif
1055
1056 #define SymI_HasProto(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
1057                     (void*)(&(vvv)) },
1058 #define SymE_HasProto(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
1059             (void*)DLL_IMPORT_DATA_REF(vvv) },
1060
1061 #define SymI_NeedsProto(vvv) SymI_HasProto(vvv)
1062 #define SymE_NeedsProto(vvv) SymE_HasProto(vvv)
1063
1064 // SymI_HasProto_redirect allows us to redirect references to one symbol to
1065 // another symbol.  See newCAF/newDynCAF for an example.
1066 #define SymI_HasProto_redirect(vvv,xxx)   \
1067     { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
1068       (void*)(&(xxx)) },
1069
1070 static RtsSymbolVal rtsSyms[] = {
1071       RTS_SYMBOLS
1072       RTS_RET_SYMBOLS
1073       RTS_POSIX_ONLY_SYMBOLS
1074       RTS_MINGW_ONLY_SYMBOLS
1075       RTS_CYGWIN_ONLY_SYMBOLS
1076       RTS_DARWIN_ONLY_SYMBOLS
1077       RTS_LIBGCC_SYMBOLS
1078       RTS_LIBFFI_SYMBOLS
1079 #if defined(darwin_HOST_OS) && defined(i386_HOST_ARCH)
1080       // dyld stub code contains references to this,
1081       // but it should never be called because we treat
1082       // lazy pointers as nonlazy.
1083       { "dyld_stub_binding_helper", (void*)0xDEADBEEF },
1084 #endif
1085       { 0, 0 } /* sentinel */
1086 };
1087
1088
1089
1090 /* -----------------------------------------------------------------------------
1091  * Insert symbols into hash tables, checking for duplicates.
1092  */
1093
1094 static void ghciInsertStrHashTable ( char* obj_name,
1095                                      HashTable *table,
1096                                      char* key,
1097                                      void *data
1098                                    )
1099 {
1100    if (lookupHashTable(table, (StgWord)key) == NULL)
1101    {
1102       insertStrHashTable(table, (StgWord)key, data);
1103       return;
1104    }
1105    debugBelch(
1106       "\n\n"
1107       "GHCi runtime linker: fatal error: I found a duplicate definition for symbol\n"
1108       "   %s\n"
1109       "whilst processing object file\n"
1110       "   %s\n"
1111       "This could be caused by:\n"
1112       "   * Loading two different object files which export the same symbol\n"
1113       "   * Specifying the same object file twice on the GHCi command line\n"
1114       "   * An incorrect `package.conf' entry, causing some object to be\n"
1115       "     loaded twice.\n"
1116       "GHCi cannot safely continue in this situation.  Exiting now.  Sorry.\n"
1117       "\n",
1118       (char*)key,
1119       obj_name
1120    );
1121    stg_exit(1);
1122 }
1123 /* -----------------------------------------------------------------------------
1124  * initialize the object linker
1125  */
1126
1127
1128 static int linker_init_done = 0 ;
1129
1130 #if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1131 static void *dl_prog_handle;
1132 static regex_t re_invalid;
1133 static regex_t re_realso;
1134 #ifdef THREADED_RTS
1135 static Mutex dl_mutex; // mutex to protect dlopen/dlerror critical section
1136 #endif
1137 #endif
1138
1139 void
1140 initLinker( void )
1141 {
1142     RtsSymbolVal *sym;
1143 #if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1144     int compileResult;
1145 #endif
1146
1147     IF_DEBUG(linker, debugBelch("initLinker: start\n"));
1148
1149     /* Make initLinker idempotent, so we can call it
1150        before evey relevant operation; that means we
1151        don't need to initialise the linker separately */
1152     if (linker_init_done == 1) {
1153         IF_DEBUG(linker, debugBelch("initLinker: idempotent return\n"));
1154         return;
1155     } else {
1156         linker_init_done = 1;
1157     }
1158
1159 #if defined(THREADED_RTS) && (defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO))
1160     initMutex(&dl_mutex);
1161 #endif
1162     stablehash = allocStrHashTable();
1163     symhash = allocStrHashTable();
1164
1165     /* populate the symbol table with stuff from the RTS */
1166     for (sym = rtsSyms; sym->lbl != NULL; sym++) {
1167         ghciInsertStrHashTable("(GHCi built-in symbols)",
1168                                symhash, sym->lbl, sym->addr);
1169         IF_DEBUG(linker, debugBelch("initLinker: inserting rts symbol %s, %p\n", sym->lbl, sym->addr));
1170     }
1171 #   if defined(OBJFORMAT_MACHO) && defined(powerpc_HOST_ARCH)
1172     machoInitSymbolsWithoutUnderscore();
1173 #   endif
1174
1175 #   if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1176 #   if defined(RTLD_DEFAULT)
1177     dl_prog_handle = RTLD_DEFAULT;
1178 #   else
1179     dl_prog_handle = dlopen(NULL, RTLD_LAZY);
1180 #   endif /* RTLD_DEFAULT */
1181
1182     compileResult = regcomp(&re_invalid,
1183            "(([^ \t()])+\\.so([^ \t:()])*):([ \t])*invalid ELF header",
1184            REG_EXTENDED);
1185     ASSERT( compileResult == 0 );
1186     compileResult = regcomp(&re_realso,
1187            "GROUP *\\( *(([^ )])+)",
1188            REG_EXTENDED);
1189     ASSERT( compileResult == 0 );
1190 #   endif
1191
1192 #if !defined(ALWAYS_PIC) && defined(x86_64_HOST_ARCH)
1193     if (RtsFlags.MiscFlags.linkerMemBase != 0) {
1194         // User-override for mmap_32bit_base
1195         mmap_32bit_base = (void*)RtsFlags.MiscFlags.linkerMemBase;
1196     }
1197 #endif
1198
1199 #if defined(mingw32_HOST_OS)
1200     /*
1201      * These two libraries cause problems when added to the static link,
1202      * but are necessary for resolving symbols in GHCi, hence we load
1203      * them manually here.
1204      */
1205     addDLL("msvcrt");
1206     addDLL("kernel32");
1207 #endif
1208
1209     IF_DEBUG(linker, debugBelch("initLinker: done\n"));
1210     return;
1211 }
1212
1213 void
1214 exitLinker( void ) {
1215 #if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1216    if (linker_init_done == 1) {
1217       regfree(&re_invalid);
1218       regfree(&re_realso);
1219 #ifdef THREADED_RTS
1220       closeMutex(&dl_mutex);
1221 #endif
1222    }
1223 #endif
1224 }
1225
1226 /* -----------------------------------------------------------------------------
1227  *                  Loading DLL or .so dynamic libraries
1228  * -----------------------------------------------------------------------------
1229  *
1230  * Add a DLL from which symbols may be found.  In the ELF case, just
1231  * do RTLD_GLOBAL-style add, so no further messing around needs to
1232  * happen in order that symbols in the loaded .so are findable --
1233  * lookupSymbol() will subsequently see them by dlsym on the program's
1234  * dl-handle.  Returns NULL if success, otherwise ptr to an err msg.
1235  *
1236  * In the PEi386 case, open the DLLs and put handles to them in a
1237  * linked list.  When looking for a symbol, try all handles in the
1238  * list.  This means that we need to load even DLLs that are guaranteed
1239  * to be in the ghc.exe image already, just so we can get a handle
1240  * to give to loadSymbol, so that we can find the symbols.  For such
1241  * libraries, the LoadLibrary call should be a no-op except for returning
1242  * the handle.
1243  *
1244  */
1245
1246 #if defined(OBJFORMAT_PEi386)
1247 /* A record for storing handles into DLLs. */
1248
1249 typedef
1250    struct _OpenedDLL {
1251       char*              name;
1252       struct _OpenedDLL* next;
1253       HINSTANCE instance;
1254    }
1255    OpenedDLL;
1256
1257 /* A list thereof. */
1258 static OpenedDLL* opened_dlls = NULL;
1259 #endif
1260
1261 #  if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1262
1263 static const char *
1264 internal_dlopen(const char *dll_name)
1265 {
1266    void *hdl;
1267    const char *errmsg;
1268    char *errmsg_copy;
1269
1270    // omitted: RTLD_NOW
1271    // see http://www.haskell.org/pipermail/cvs-ghc/2007-September/038570.html
1272    IF_DEBUG(linker,
1273       debugBelch("internal_dlopen: dll_name = '%s'\n", dll_name));
1274
1275    //-------------- Begin critical section ------------------
1276    // This critical section is necessary because dlerror() is not
1277    // required to be reentrant (see POSIX -- IEEE Std 1003.1-2008)
1278    // Also, the error message returned must be copied to preserve it
1279    // (see POSIX also)
1280
1281    ACQUIRE_LOCK(&dl_mutex);
1282    hdl = dlopen(dll_name, RTLD_LAZY | RTLD_GLOBAL);
1283
1284    errmsg = NULL;
1285    if (hdl == NULL) {
1286       /* dlopen failed; return a ptr to the error msg. */
1287       errmsg = dlerror();
1288       if (errmsg == NULL) errmsg = "addDLL: unknown error";
1289       errmsg_copy = stgMallocBytes(strlen(errmsg)+1, "addDLL");
1290       strcpy(errmsg_copy, errmsg);
1291       errmsg = errmsg_copy;
1292    }
1293    RELEASE_LOCK(&dl_mutex);
1294    //--------------- End critical section -------------------
1295
1296    return errmsg;
1297 }
1298 #  endif
1299
1300 const char *
1301 addDLL( char *dll_name )
1302 {
1303 #  if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1304    /* ------------------- ELF DLL loader ------------------- */
1305
1306 #define NMATCH 5
1307    regmatch_t match[NMATCH];
1308    const char *errmsg;
1309    FILE* fp;
1310    size_t match_length;
1311 #define MAXLINE 1000
1312    char line[MAXLINE];
1313    int result;
1314
1315    initLinker();
1316
1317    IF_DEBUG(linker, debugBelch("addDLL: dll_name = '%s'\n", dll_name));
1318    errmsg = internal_dlopen(dll_name);
1319
1320    if (errmsg == NULL) {
1321       return NULL;
1322    }
1323
1324    // GHC Trac ticket #2615
1325    // On some systems (e.g., Gentoo Linux) dynamic files (e.g. libc.so)
1326    // contain linker scripts rather than ELF-format object code. This
1327    // code handles the situation by recognizing the real object code
1328    // file name given in the linker script.
1329    //
1330    // If an "invalid ELF header" error occurs, it is assumed that the
1331    // .so file contains a linker script instead of ELF object code.
1332    // In this case, the code looks for the GROUP ( ... ) linker
1333    // directive. If one is found, the first file name inside the
1334    // parentheses is treated as the name of a dynamic library and the
1335    // code attempts to dlopen that file. If this is also unsuccessful,
1336    // an error message is returned.
1337
1338    // see if the error message is due to an invalid ELF header
1339    IF_DEBUG(linker, debugBelch("errmsg = '%s'\n", errmsg));
1340    result = regexec(&re_invalid, errmsg, (size_t) NMATCH, match, 0);
1341    IF_DEBUG(linker, debugBelch("result = %i\n", result));
1342    if (result == 0) {
1343       // success -- try to read the named file as a linker script
1344       match_length = (size_t) stg_min((match[1].rm_eo - match[1].rm_so),
1345                                  MAXLINE-1);
1346       strncpy(line, (errmsg+(match[1].rm_so)),match_length);
1347       line[match_length] = '\0'; // make sure string is null-terminated
1348       IF_DEBUG(linker, debugBelch ("file name = '%s'\n", line));
1349       if ((fp = fopen(line, "r")) == NULL) {
1350          return errmsg; // return original error if open fails
1351       }
1352       // try to find a GROUP ( ... ) command
1353       while (fgets(line, MAXLINE, fp) != NULL) {
1354          IF_DEBUG(linker, debugBelch("input line = %s", line));
1355          if (regexec(&re_realso, line, (size_t) NMATCH, match, 0) == 0) {
1356             // success -- try to dlopen the first named file
1357             IF_DEBUG(linker, debugBelch("match%s\n",""));
1358             line[match[1].rm_eo] = '\0';
1359             errmsg = internal_dlopen(line+match[1].rm_so);
1360             break;
1361          }
1362          // if control reaches here, no GROUP ( ... ) directive was found
1363          // and the original error message is returned to the caller
1364       }
1365       fclose(fp);
1366    }
1367    return errmsg;
1368
1369 #  elif defined(OBJFORMAT_PEi386)
1370    /* ------------------- Win32 DLL loader ------------------- */
1371
1372    char*      buf;
1373    OpenedDLL* o_dll;
1374    HINSTANCE  instance;
1375
1376    initLinker();
1377
1378    /* debugBelch("\naddDLL; dll_name = `%s'\n", dll_name); */
1379
1380    /* See if we've already got it, and ignore if so. */
1381    for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
1382       if (0 == strcmp(o_dll->name, dll_name))
1383          return NULL;
1384    }
1385
1386    /* The file name has no suffix (yet) so that we can try
1387       both foo.dll and foo.drv
1388
1389       The documentation for LoadLibrary says:
1390         If no file name extension is specified in the lpFileName
1391         parameter, the default library extension .dll is
1392         appended. However, the file name string can include a trailing
1393         point character (.) to indicate that the module name has no
1394         extension. */
1395
1396    buf = stgMallocBytes(strlen(dll_name) + 10, "addDLL");
1397    sprintf(buf, "%s.DLL", dll_name);
1398    instance = LoadLibrary(buf);
1399    if (instance == NULL) {
1400        if (GetLastError() != ERROR_MOD_NOT_FOUND) goto error;
1401        // KAA: allow loading of drivers (like winspool.drv)
1402        sprintf(buf, "%s.DRV", dll_name);
1403        instance = LoadLibrary(buf);
1404        if (instance == NULL) {
1405            if (GetLastError() != ERROR_MOD_NOT_FOUND) goto error;
1406            // #1883: allow loading of unix-style libfoo.dll DLLs
1407            sprintf(buf, "lib%s.DLL", dll_name);
1408            instance = LoadLibrary(buf);
1409            if (instance == NULL) {
1410                goto error;
1411            }
1412        }
1413    }
1414    stgFree(buf);
1415
1416    /* Add this DLL to the list of DLLs in which to search for symbols. */
1417    o_dll = stgMallocBytes( sizeof(OpenedDLL), "addDLL" );
1418    o_dll->name     = stgMallocBytes(1+strlen(dll_name), "addDLL");
1419    strcpy(o_dll->name, dll_name);
1420    o_dll->instance = instance;
1421    o_dll->next     = opened_dlls;
1422    opened_dlls     = o_dll;
1423
1424    return NULL;
1425
1426 error:
1427    stgFree(buf);
1428    sysErrorBelch(dll_name);
1429
1430    /* LoadLibrary failed; return a ptr to the error msg. */
1431    return "addDLL: could not load DLL";
1432
1433 #  else
1434    barf("addDLL: not implemented on this platform");
1435 #  endif
1436 }
1437
1438 /* -----------------------------------------------------------------------------
1439  * insert a stable symbol in the hash table
1440  */
1441
1442 void
1443 insertStableSymbol(char* obj_name, char* key, StgPtr p)
1444 {
1445   ghciInsertStrHashTable(obj_name, stablehash, key, getStablePtr(p));
1446 }
1447
1448
1449 /* -----------------------------------------------------------------------------
1450  * insert a symbol in the hash table
1451  */
1452 void
1453 insertSymbol(char* obj_name, char* key, void* data)
1454 {
1455   ghciInsertStrHashTable(obj_name, symhash, key, data);
1456 }
1457
1458 /* -----------------------------------------------------------------------------
1459  * lookup a symbol in the hash table
1460  */
1461 void *
1462 lookupSymbol( char *lbl )
1463 {
1464     void *val;
1465     IF_DEBUG(linker, debugBelch("lookupSymbol: looking up %s\n", lbl));
1466     initLinker() ;
1467     ASSERT(symhash != NULL);
1468     val = lookupStrHashTable(symhash, lbl);
1469
1470     if (val == NULL) {
1471         IF_DEBUG(linker, debugBelch("lookupSymbol: symbol not found\n"));
1472 #       if defined(OBJFORMAT_ELF)
1473         return dlsym(dl_prog_handle, lbl);
1474 #       elif defined(OBJFORMAT_MACHO)
1475 #       if HAVE_DLFCN_H
1476         /* On OS X 10.3 and later, we use dlsym instead of the old legacy
1477            interface.
1478
1479            HACK: On OS X, global symbols are prefixed with an underscore.
1480                  However, dlsym wants us to omit the leading underscore from the
1481                  symbol name. For now, we simply strip it off here (and ONLY
1482                  here).
1483         */
1484         IF_DEBUG(linker, debugBelch("lookupSymbol: looking up %s with dlsym\n", lbl));
1485         ASSERT(lbl[0] == '_');
1486         return dlsym(dl_prog_handle, lbl+1);
1487 #       else
1488         if(NSIsSymbolNameDefined(lbl)) {
1489             NSSymbol symbol = NSLookupAndBindSymbol(lbl);
1490             return NSAddressOfSymbol(symbol);
1491         } else {
1492             return NULL;
1493         }
1494 #       endif /* HAVE_DLFCN_H */
1495 #       elif defined(OBJFORMAT_PEi386)
1496         void* sym;
1497
1498         sym = lookupSymbolInDLLs((unsigned char*)lbl);
1499         if (sym != NULL) { return sym; };
1500
1501         // Also try looking up the symbol without the @N suffix.  Some
1502         // DLLs have the suffixes on their symbols, some don't.
1503         zapTrailingAtSign ( (unsigned char*)lbl );
1504         sym = lookupSymbolInDLLs((unsigned char*)lbl);
1505         if (sym != NULL) { return sym; };
1506         return NULL;
1507
1508 #       else
1509         ASSERT(2+2 == 5);
1510         return NULL;
1511 #       endif
1512     } else {
1513         IF_DEBUG(linker, debugBelch("lookupSymbol: value of %s is %p\n", lbl, val));
1514         return val;
1515     }
1516 }
1517
1518 /* -----------------------------------------------------------------------------
1519  * Debugging aid: look in GHCi's object symbol tables for symbols
1520  * within DELTA bytes of the specified address, and show their names.
1521  */
1522 #ifdef DEBUG
1523 void ghci_enquire ( char* addr );
1524
1525 void ghci_enquire ( char* addr )
1526 {
1527    int   i;
1528    char* sym;
1529    char* a;
1530    const int DELTA = 64;
1531    ObjectCode* oc;
1532
1533    initLinker();
1534
1535    for (oc = objects; oc; oc = oc->next) {
1536       for (i = 0; i < oc->n_symbols; i++) {
1537          sym = oc->symbols[i];
1538          if (sym == NULL) continue;
1539          a = NULL;
1540          if (a == NULL) {
1541             a = lookupStrHashTable(symhash, sym);
1542          }
1543          if (a == NULL) {
1544              // debugBelch("ghci_enquire: can't find %s\n", sym);
1545          }
1546          else if (addr-DELTA <= a && a <= addr+DELTA) {
1547             debugBelch("%p + %3d  ==  `%s'\n", addr, (int)(a - addr), sym);
1548          }
1549       }
1550    }
1551 }
1552 #endif
1553
1554 #ifdef USE_MMAP
1555 #define ROUND_UP(x,size) ((x + size - 1) & ~(size - 1))
1556
1557 static void *
1558 mmapForLinker (size_t bytes, nat flags, int fd)
1559 {
1560    void *map_addr = NULL;
1561    void *result;
1562    int pagesize, size;
1563    static nat fixed = 0;
1564
1565    pagesize = getpagesize();
1566    size = ROUND_UP(bytes, pagesize);
1567
1568 #if !defined(ALWAYS_PIC) && defined(x86_64_HOST_ARCH)
1569 mmap_again:
1570
1571    if (mmap_32bit_base != 0) {
1572        map_addr = mmap_32bit_base;
1573    }
1574 #endif
1575
1576    result = mmap(map_addr, size, PROT_EXEC|PROT_READ|PROT_WRITE,
1577                     MAP_PRIVATE|TRY_MAP_32BIT|fixed|flags, fd, 0);
1578
1579    if (result == MAP_FAILED) {
1580        sysErrorBelch("mmap %lu bytes at %p",(lnat)size,map_addr);
1581        errorBelch("Try specifying an address with +RTS -xm<addr> -RTS");
1582        stg_exit(EXIT_FAILURE);
1583    }
1584
1585 #if !defined(ALWAYS_PIC) && defined(x86_64_HOST_ARCH)
1586    if (mmap_32bit_base != 0) {
1587        if (result == map_addr) {
1588            mmap_32bit_base = (StgWord8*)map_addr + size;
1589        } else {
1590            if ((W_)result > 0x80000000) {
1591                // oops, we were given memory over 2Gb
1592 #if defined(freebsd_HOST_OS) || defined(dragonfly_HOST_OS)
1593                // Some platforms require MAP_FIXED.  This is normally
1594                // a bad idea, because MAP_FIXED will overwrite
1595                // existing mappings.
1596                munmap(result,size);
1597                fixed = MAP_FIXED;
1598                goto mmap_again;
1599 #else
1600                barf("loadObj: failed to mmap() memory below 2Gb; asked for %lu bytes at %p.  Try specifying an address with +RTS -xm<addr> -RTS", size, map_addr, result);
1601 #endif
1602            } else {
1603                // hmm, we were given memory somewhere else, but it's
1604                // still under 2Gb so we can use it.  Next time, ask
1605                // for memory right after the place we just got some
1606                mmap_32bit_base = (StgWord8*)result + size;
1607            }
1608        }
1609    } else {
1610        if ((W_)result > 0x80000000) {
1611            // oops, we were given memory over 2Gb
1612            // ... try allocating memory somewhere else?;
1613            debugTrace(DEBUG_linker,"MAP_32BIT didn't work; gave us %lu bytes at 0x%p", bytes, result);
1614            munmap(result, size);
1615
1616            // Set a base address and try again... (guess: 1Gb)
1617            mmap_32bit_base = (void*)0x40000000;
1618            goto mmap_again;
1619        }
1620    }
1621 #endif
1622
1623    return result;
1624 }
1625 #endif // USE_MMAP
1626
1627 static ObjectCode*
1628 mkOc( char *path, char *image, int imageSize,
1629       char *archiveMemberName
1630 #ifndef USE_MMAP
1631 #ifdef darwin_HOST_OS
1632     , int misalignment
1633 #endif
1634 #endif
1635     ) {
1636    ObjectCode* oc;
1637
1638    oc = stgMallocBytes(sizeof(ObjectCode), "loadArchive(oc)");
1639
1640 #  if defined(OBJFORMAT_ELF)
1641    oc->formatName = "ELF";
1642 #  elif defined(OBJFORMAT_PEi386)
1643    oc->formatName = "PEi386";
1644 #  elif defined(OBJFORMAT_MACHO)
1645    oc->formatName = "Mach-O";
1646 #  else
1647    stgFree(oc);
1648    barf("loadObj: not implemented on this platform");
1649 #  endif
1650
1651    oc->image = image;
1652    /* sigh, strdup() isn't a POSIX function, so do it the long way */
1653    oc->fileName = stgMallocBytes( strlen(path)+1, "loadObj" );
1654    strcpy(oc->fileName, path);
1655
1656    if (archiveMemberName) {
1657        oc->archiveMemberName = stgMallocBytes( strlen(archiveMemberName)+1, "loadObj" );
1658        strcpy(oc->archiveMemberName, archiveMemberName);
1659    }
1660    else {
1661        oc->archiveMemberName = NULL;
1662    }
1663
1664    oc->fileSize          = imageSize;
1665    oc->symbols           = NULL;
1666    oc->sections          = NULL;
1667    oc->proddables        = NULL;
1668
1669 #ifndef USE_MMAP
1670 #ifdef darwin_HOST_OS
1671    oc->misalignment = misalignment;
1672 #endif
1673 #endif
1674
1675    /* chain it onto the list of objects */
1676    oc->next              = objects;
1677    objects               = oc;
1678
1679    return oc;
1680 }
1681
1682 HsInt
1683 loadArchive( char *path )
1684 {
1685     ObjectCode* oc;
1686     char *image;
1687     int memberSize;
1688     FILE *f;
1689     int n;
1690     size_t thisFileNameSize;
1691     char *fileName;
1692     size_t fileNameSize;
1693     int isObject, isGnuIndex;
1694     char tmp[12];
1695     char *gnuFileIndex;
1696     int gnuFileIndexSize;
1697 #if !defined(USE_MMAP) && defined(darwin_HOST_OS)
1698     int misalignment;
1699 #endif
1700
1701     IF_DEBUG(linker, debugBelch("loadArchive: Loading archive `%s'\n", path));
1702
1703     gnuFileIndex = NULL;
1704     gnuFileIndexSize = 0;
1705
1706     fileNameSize = 32;
1707     fileName = stgMallocBytes(fileNameSize, "loadArchive(fileName)");
1708
1709     f = fopen(path, "rb");
1710     if (!f)
1711         barf("loadObj: can't read `%s'", path);
1712
1713     n = fread ( tmp, 1, 8, f );
1714     if (strncmp(tmp, "!<arch>\n", 8) != 0)
1715         barf("loadArchive: Not an archive: `%s'", path);
1716
1717     while(1) {
1718         n = fread ( fileName, 1, 16, f );
1719         if (n != 16) {
1720             if (feof(f)) {
1721                 break;
1722             }
1723             else {
1724                 barf("loadArchive: Failed reading file name from `%s'", path);
1725             }
1726         }
1727         n = fread ( tmp, 1, 12, f );
1728         if (n != 12)
1729             barf("loadArchive: Failed reading mod time from `%s'", path);
1730         n = fread ( tmp, 1, 6, f );
1731         if (n != 6)
1732             barf("loadArchive: Failed reading owner from `%s'", path);
1733         n = fread ( tmp, 1, 6, f );
1734         if (n != 6)
1735             barf("loadArchive: Failed reading group from `%s'", path);
1736         n = fread ( tmp, 1, 8, f );
1737         if (n != 8)
1738             barf("loadArchive: Failed reading mode from `%s'", path);
1739         n = fread ( tmp, 1, 10, f );
1740         if (n != 10)
1741             barf("loadArchive: Failed reading size from `%s'", path);
1742         tmp[10] = '\0';
1743         for (n = 0; isdigit(tmp[n]); n++);
1744         tmp[n] = '\0';
1745         memberSize = atoi(tmp);
1746         n = fread ( tmp, 1, 2, f );
1747         if (strncmp(tmp, "\x60\x0A", 2) != 0)
1748             barf("loadArchive: Failed reading magic from `%s' at %ld. Got %c%c",
1749                  path, ftell(f), tmp[0], tmp[1]);
1750
1751         isGnuIndex = 0;
1752         /* Check for BSD-variant large filenames */
1753         if (0 == strncmp(fileName, "#1/", 3)) {
1754             fileName[16] = '\0';
1755             if (isdigit(fileName[3])) {
1756                 for (n = 4; isdigit(fileName[n]); n++);
1757                 fileName[n] = '\0';
1758                 thisFileNameSize = atoi(fileName + 3);
1759                 memberSize -= thisFileNameSize;
1760                 if (thisFileNameSize >= fileNameSize) {
1761                     /* Double it to avoid potentially continually
1762                        increasing it by 1 */
1763                     fileNameSize = thisFileNameSize * 2;
1764                     fileName = stgReallocBytes(fileName, fileNameSize, "loadArchive(fileName)");
1765                 }
1766                 n = fread ( fileName, 1, thisFileNameSize, f );
1767                 if (n != (int)thisFileNameSize) {
1768                     barf("loadArchive: Failed reading filename from `%s'",
1769                          path);
1770                 }
1771                 fileName[thisFileNameSize] = 0;
1772             }
1773             else {
1774                 barf("loadArchive: BSD-variant filename size not found while reading filename from `%s'", path);
1775             }
1776         }
1777         /* Check for GNU file index file */
1778         else if (0 == strncmp(fileName, "//", 2)) {
1779             fileName[0] = '\0';
1780             thisFileNameSize = 0;
1781             isGnuIndex = 1;
1782         }
1783         /* Check for a file in the GNU file index */
1784         else if (fileName[0] == '/') {
1785             if (isdigit(fileName[1])) {
1786                 int i;
1787
1788                 for (n = 2; isdigit(fileName[n]); n++);
1789                 fileName[n] = '\0';
1790                 n = atoi(fileName + 1);
1791
1792                 if (gnuFileIndex == NULL) {
1793                     barf("loadArchive: GNU-variant filename without an index while reading from `%s'", path);
1794                 }
1795                 if (n < 0 || n > gnuFileIndexSize) {
1796                     barf("loadArchive: GNU-variant filename offset %d out of range [0..%d] while reading filename from `%s'", n, gnuFileIndexSize, path);
1797                 }
1798                 if (n != 0 && gnuFileIndex[n - 1] != '\n') {
1799                     barf("loadArchive: GNU-variant filename offset %d invalid (range [0..%d]) while reading filename from `%s'", n, gnuFileIndexSize, path);
1800                 }
1801                 for (i = n; gnuFileIndex[i] != '/'; i++);
1802                 thisFileNameSize = i - n;
1803                 if (thisFileNameSize >= fileNameSize) {
1804                     /* Double it to avoid potentially continually
1805                        increasing it by 1 */
1806                     fileNameSize = thisFileNameSize * 2;
1807                     fileName = stgReallocBytes(fileName, fileNameSize, "loadArchive(fileName)");
1808                 }
1809                 memcpy(fileName, gnuFileIndex + n, thisFileNameSize);
1810                 fileName[thisFileNameSize] = '\0';
1811             }
1812             else if (fileName[1] == ' ') {
1813                 fileName[0] = '\0';
1814                 thisFileNameSize = 0;
1815             }
1816             else {
1817                 barf("loadArchive: GNU-variant filename offset not found while reading filename from `%s'", path);
1818             }
1819         }
1820         /* Finally, the case where the filename field actually contains
1821            the filename */
1822         else {
1823             /* GNU ar terminates filenames with a '/', this allowing
1824                spaces in filenames. So first look to see if there is a
1825                terminating '/'. */
1826             for (thisFileNameSize = 0;
1827                  thisFileNameSize < 16;
1828                  thisFileNameSize++) {
1829                 if (fileName[thisFileNameSize] == '/') {
1830                     fileName[thisFileNameSize] = '\0';
1831                     break;
1832                 }
1833             }
1834             /* If we didn't find a '/', then a space teminates the
1835                filename. Note that if we don't find one, then
1836                thisFileNameSize ends up as 16, and we already have the
1837                '\0' at the end. */
1838             if (thisFileNameSize == 16) {
1839                 for (thisFileNameSize = 0;
1840                      thisFileNameSize < 16;
1841                      thisFileNameSize++) {
1842                     if (fileName[thisFileNameSize] == ' ') {
1843                         fileName[thisFileNameSize] = '\0';
1844                         break;
1845                     }
1846                 }
1847             }
1848         }
1849
1850         IF_DEBUG(linker,
1851                  debugBelch("loadArchive: Found member file `%s'\n", fileName));
1852
1853         isObject = thisFileNameSize >= 2
1854                 && fileName[thisFileNameSize - 2] == '.'
1855                 && fileName[thisFileNameSize - 1] == 'o';
1856
1857         if (isObject) {
1858             char *archiveMemberName;
1859
1860             IF_DEBUG(linker, debugBelch("loadArchive: Member is an object file...loading...\n"));
1861
1862             /* We can't mmap from the archive directly, as object
1863                files need to be 8-byte aligned but files in .ar
1864                archives are 2-byte aligned. When possible we use mmap
1865                to get some anonymous memory, as on 64-bit platforms if
1866                we use malloc then we can be given memory above 2^32.
1867                In the mmap case we're probably wasting lots of space;
1868                we could do better. */
1869 #if defined(USE_MMAP)
1870             image = mmapForLinker(memberSize, MAP_ANONYMOUS, -1);
1871 #elif defined(darwin_HOST_OS)
1872             /* See loadObj() */
1873             misalignment = machoGetMisalignment(f);
1874             image = stgMallocBytes(memberSize + misalignment, "loadArchive(image)");
1875             image += misalignment;
1876 #else
1877             image = stgMallocBytes(memberSize, "loadArchive(image)");
1878 #endif
1879             n = fread ( image, 1, memberSize, f );
1880             if (n != memberSize) {
1881                 barf("loadArchive: error whilst reading `%s'", path);
1882             }
1883
1884             archiveMemberName = stgMallocBytes(strlen(path) + thisFileNameSize + 3,
1885                                                "loadArchive(file)");
1886             sprintf(archiveMemberName, "%s(%.*s)",
1887                     path, (int)thisFileNameSize, fileName);
1888
1889             oc = mkOc(path, image, memberSize, archiveMemberName
1890 #ifndef USE_MMAP
1891 #ifdef darwin_HOST_OS
1892                      , misalignment
1893 #endif
1894 #endif
1895                      );
1896
1897             stgFree(archiveMemberName);
1898
1899             if (0 == loadOc(oc)) {
1900                 stgFree(fileName);
1901                 return 0;
1902             }
1903         }
1904         else if (isGnuIndex) {
1905             if (gnuFileIndex != NULL) {
1906                 barf("loadArchive: GNU-variant index found, but already have an index, while reading filename from `%s'", path);
1907             }
1908             IF_DEBUG(linker, debugBelch("loadArchive: Found GNU-variant file index\n"));
1909 #ifdef USE_MMAP
1910             gnuFileIndex = mmapForLinker(memberSize + 1, MAP_ANONYMOUS, -1);
1911 #else
1912             gnuFileIndex = stgMallocBytes(memberSize + 1, "loadArchive(image)");
1913 #endif
1914             n = fread ( gnuFileIndex, 1, memberSize, f );
1915             if (n != memberSize) {
1916                 barf("loadArchive: error whilst reading `%s'", path);
1917             }
1918             gnuFileIndex[memberSize] = '/';
1919             gnuFileIndexSize = memberSize;
1920         }
1921         else {
1922             n = fseek(f, memberSize, SEEK_CUR);
1923             if (n != 0)
1924                 barf("loadArchive: error whilst seeking by %d in `%s'",
1925                      memberSize, path);
1926         }
1927         /* .ar files are 2-byte aligned */
1928         if (memberSize % 2) {
1929             n = fread ( tmp, 1, 1, f );
1930             if (n != 1) {
1931                 if (feof(f)) {
1932                     break;
1933                 }
1934                 else {
1935                     barf("loadArchive: Failed reading padding from `%s'", path);
1936                 }
1937             }
1938         }
1939     }
1940
1941     fclose(f);
1942
1943     stgFree(fileName);
1944     if (gnuFileIndex != NULL) {
1945 #ifdef USE_MMAP
1946         munmap(gnuFileIndex, gnuFileIndexSize + 1);
1947 #else
1948         stgFree(gnuFileIndex);
1949 #endif
1950     }
1951
1952     return 1;
1953 }
1954
1955 /* -----------------------------------------------------------------------------
1956  * Load an obj (populate the global symbol table, but don't resolve yet)
1957  *
1958  * Returns: 1 if ok, 0 on error.
1959  */
1960 HsInt
1961 loadObj( char *path )
1962 {
1963    ObjectCode* oc;
1964    char *image;
1965    int fileSize;
1966    struct stat st;
1967    int r;
1968 #ifdef USE_MMAP
1969    int fd;
1970 #else
1971    FILE *f;
1972 #  if defined(darwin_HOST_OS)
1973    int misalignment;
1974 #  endif
1975 #endif
1976    IF_DEBUG(linker, debugBelch("loadObj %s\n", path));
1977
1978    initLinker();
1979
1980    /* debugBelch("loadObj %s\n", path ); */
1981
1982    /* Check that we haven't already loaded this object.
1983       Ignore requests to load multiple times */
1984    {
1985        ObjectCode *o;
1986        int is_dup = 0;
1987        for (o = objects; o; o = o->next) {
1988           if (0 == strcmp(o->fileName, path)) {
1989              is_dup = 1;
1990              break; /* don't need to search further */
1991           }
1992        }
1993        if (is_dup) {
1994           IF_DEBUG(linker, debugBelch(
1995             "GHCi runtime linker: warning: looks like you're trying to load the\n"
1996             "same object file twice:\n"
1997             "   %s\n"
1998             "GHCi will ignore this, but be warned.\n"
1999             , path));
2000           return 1; /* success */
2001        }
2002    }
2003
2004    r = stat(path, &st);
2005    if (r == -1) {
2006        IF_DEBUG(linker, debugBelch("File doesn't exist\n"));
2007        return 0;
2008    }
2009
2010    fileSize = st.st_size;
2011
2012 #ifdef USE_MMAP
2013    /* On many architectures malloc'd memory isn't executable, so we need to use mmap. */
2014
2015 #if defined(openbsd_HOST_OS)
2016    fd = open(path, O_RDONLY, S_IRUSR);
2017 #else
2018    fd = open(path, O_RDONLY);
2019 #endif
2020    if (fd == -1)
2021       barf("loadObj: can't open `%s'", path);
2022
2023    image = mmapForLinker(fileSize, 0, fd);
2024
2025    close(fd);
2026
2027 #else /* !USE_MMAP */
2028    /* load the image into memory */
2029    f = fopen(path, "rb");
2030    if (!f)
2031        barf("loadObj: can't read `%s'", path);
2032
2033 #   if defined(mingw32_HOST_OS)
2034         // TODO: We would like to use allocateExec here, but allocateExec
2035         //       cannot currently allocate blocks large enough.
2036     image = VirtualAlloc(NULL, fileSize, MEM_RESERVE | MEM_COMMIT,
2037                              PAGE_EXECUTE_READWRITE);
2038 #   elif defined(darwin_HOST_OS)
2039     // In a Mach-O .o file, all sections can and will be misaligned
2040     // if the total size of the headers is not a multiple of the
2041     // desired alignment. This is fine for .o files that only serve
2042     // as input for the static linker, but it's not fine for us,
2043     // as SSE (used by gcc for floating point) and Altivec require
2044     // 16-byte alignment.
2045     // We calculate the correct alignment from the header before
2046     // reading the file, and then we misalign image on purpose so
2047     // that the actual sections end up aligned again.
2048    misalignment = machoGetMisalignment(f);
2049    image = stgMallocBytes(fileSize + misalignment, "loadObj(image)");
2050    image += misalignment;
2051 #  else
2052    image = stgMallocBytes(fileSize, "loadObj(image)");
2053 #  endif
2054
2055    {
2056        int n;
2057        n = fread ( image, 1, fileSize, f );
2058        if (n != fileSize)
2059            barf("loadObj: error whilst reading `%s'", path);
2060    }
2061    fclose(f);
2062 #endif /* USE_MMAP */
2063
2064    oc = mkOc(path, image, fileSize, NULL
2065 #ifndef USE_MMAP
2066 #ifdef darwin_HOST_OS
2067             , misalignment
2068 #endif
2069 #endif
2070             );
2071
2072    return loadOc(oc);
2073 }
2074
2075 static HsInt
2076 loadOc( ObjectCode* oc ) {
2077    int r;
2078
2079    IF_DEBUG(linker, debugBelch("loadOc\n"));
2080
2081 #  if defined(OBJFORMAT_MACHO) && (defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH))
2082    r = ocAllocateSymbolExtras_MachO ( oc );
2083    if (!r) {
2084        IF_DEBUG(linker, debugBelch("ocAllocateSymbolExtras_MachO failed\n"));
2085        return r;
2086    }
2087 #  elif defined(OBJFORMAT_ELF) && (defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH))
2088    r = ocAllocateSymbolExtras_ELF ( oc );
2089    if (!r) {
2090        IF_DEBUG(linker, debugBelch("ocAllocateSymbolExtras_ELF failed\n"));
2091        return r;
2092    }
2093 #endif
2094
2095    /* verify the in-memory image */
2096 #  if defined(OBJFORMAT_ELF)
2097    r = ocVerifyImage_ELF ( oc );
2098 #  elif defined(OBJFORMAT_PEi386)
2099    r = ocVerifyImage_PEi386 ( oc );
2100 #  elif defined(OBJFORMAT_MACHO)
2101    r = ocVerifyImage_MachO ( oc );
2102 #  else
2103    barf("loadObj: no verify method");
2104 #  endif
2105    if (!r) {
2106        IF_DEBUG(linker, debugBelch("ocVerifyImage_* failed\n"));
2107        return r;
2108    }
2109
2110    /* build the symbol list for this image */
2111 #  if defined(OBJFORMAT_ELF)
2112    r = ocGetNames_ELF ( oc );
2113 #  elif defined(OBJFORMAT_PEi386)
2114    r = ocGetNames_PEi386 ( oc );
2115 #  elif defined(OBJFORMAT_MACHO)
2116    r = ocGetNames_MachO ( oc );
2117 #  else
2118    barf("loadObj: no getNames method");
2119 #  endif
2120    if (!r) {
2121        IF_DEBUG(linker, debugBelch("ocGetNames_* failed\n"));
2122        return r;
2123    }
2124
2125    /* loaded, but not resolved yet */
2126    oc->status = OBJECT_LOADED;
2127    IF_DEBUG(linker, debugBelch("loadObj done.\n"));
2128
2129    return 1;
2130 }
2131
2132 /* -----------------------------------------------------------------------------
2133  * resolve all the currently unlinked objects in memory
2134  *
2135  * Returns: 1 if ok, 0 on error.
2136  */
2137 HsInt
2138 resolveObjs( void )
2139 {
2140     ObjectCode *oc;
2141     int r;
2142
2143     IF_DEBUG(linker, debugBelch("resolveObjs: start\n"));
2144     initLinker();
2145
2146     for (oc = objects; oc; oc = oc->next) {
2147         if (oc->status != OBJECT_RESOLVED) {
2148 #           if defined(OBJFORMAT_ELF)
2149             r = ocResolve_ELF ( oc );
2150 #           elif defined(OBJFORMAT_PEi386)
2151             r = ocResolve_PEi386 ( oc );
2152 #           elif defined(OBJFORMAT_MACHO)
2153             r = ocResolve_MachO ( oc );
2154 #           else
2155             barf("resolveObjs: not implemented on this platform");
2156 #           endif
2157             if (!r) { return r; }
2158             oc->status = OBJECT_RESOLVED;
2159         }
2160     }
2161     IF_DEBUG(linker, debugBelch("resolveObjs: done\n"));
2162     return 1;
2163 }
2164
2165 /* -----------------------------------------------------------------------------
2166  * delete an object from the pool
2167  */
2168 HsInt
2169 unloadObj( char *path )
2170 {
2171     ObjectCode *oc, *prev;
2172     HsBool unloadedAnyObj = HS_BOOL_FALSE;
2173
2174     ASSERT(symhash != NULL);
2175     ASSERT(objects != NULL);
2176
2177     initLinker();
2178
2179     prev = NULL;
2180     for (oc = objects; oc; prev = oc, oc = oc->next) {
2181         if (!strcmp(oc->fileName,path)) {
2182
2183             /* Remove all the mappings for the symbols within this
2184              * object..
2185              */
2186             {
2187                 int i;
2188                 for (i = 0; i < oc->n_symbols; i++) {
2189                    if (oc->symbols[i] != NULL) {
2190                        removeStrHashTable(symhash, oc->symbols[i], NULL);
2191                    }
2192                 }
2193             }
2194
2195             if (prev == NULL) {
2196                 objects = oc->next;
2197             } else {
2198                 prev->next = oc->next;
2199             }
2200
2201             // We're going to leave this in place, in case there are
2202             // any pointers from the heap into it:
2203                 // #ifdef mingw32_HOST_OS
2204                 //  VirtualFree(oc->image);
2205                 // #else
2206             //  stgFree(oc->image);
2207             // #endif
2208             stgFree(oc->fileName);
2209             stgFree(oc->symbols);
2210             stgFree(oc->sections);
2211             stgFree(oc);
2212
2213             /* This could be a member of an archive so continue
2214              * unloading other members. */
2215             unloadedAnyObj = HS_BOOL_TRUE;
2216         }
2217     }
2218
2219     if (unloadedAnyObj) {
2220         return 1;
2221     }
2222     else {
2223         errorBelch("unloadObj: can't find `%s' to unload", path);
2224         return 0;
2225     }
2226 }
2227
2228 /* -----------------------------------------------------------------------------
2229  * Sanity checking.  For each ObjectCode, maintain a list of address ranges
2230  * which may be prodded during relocation, and abort if we try and write
2231  * outside any of these.
2232  */
2233 static void addProddableBlock ( ObjectCode* oc, void* start, int size )
2234 {
2235    ProddableBlock* pb
2236       = stgMallocBytes(sizeof(ProddableBlock), "addProddableBlock");
2237    IF_DEBUG(linker, debugBelch("addProddableBlock %p %p %d\n", oc, start, size));
2238    ASSERT(size > 0);
2239    pb->start      = start;
2240    pb->size       = size;
2241    pb->next       = oc->proddables;
2242    oc->proddables = pb;
2243 }
2244
2245 static void checkProddableBlock ( ObjectCode* oc, void* addr )
2246 {
2247    ProddableBlock* pb;
2248    for (pb = oc->proddables; pb != NULL; pb = pb->next) {
2249       char* s = (char*)(pb->start);
2250       char* e = s + pb->size - 1;
2251       char* a = (char*)addr;
2252       /* Assumes that the biggest fixup involves a 4-byte write.  This
2253          probably needs to be changed to 8 (ie, +7) on 64-bit
2254          plats. */
2255       if (a >= s && (a+3) <= e) return;
2256    }
2257    barf("checkProddableBlock: invalid fixup in runtime linker");
2258 }
2259
2260 /* -----------------------------------------------------------------------------
2261  * Section management.
2262  */
2263 static void addSection ( ObjectCode* oc, SectionKind kind,
2264                          void* start, void* end )
2265 {
2266    Section* s   = stgMallocBytes(sizeof(Section), "addSection");
2267    s->start     = start;
2268    s->end       = end;
2269    s->kind      = kind;
2270    s->next      = oc->sections;
2271    oc->sections = s;
2272    /*
2273    debugBelch("addSection: %p-%p (size %d), kind %d\n",
2274                    start, ((char*)end)-1, end - start + 1, kind );
2275    */
2276 }
2277
2278
2279 /* --------------------------------------------------------------------------
2280  * Symbol Extras.
2281  * This is about allocating a small chunk of memory for every symbol in the
2282  * object file. We make sure that the SymboLExtras are always "in range" of
2283  * limited-range PC-relative instructions on various platforms by allocating
2284  * them right next to the object code itself.
2285  */
2286
2287 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
2288
2289 /*
2290   ocAllocateSymbolExtras
2291
2292   Allocate additional space at the end of the object file image to make room
2293   for jump islands (powerpc, x86_64) and GOT entries (x86_64).
2294
2295   PowerPC relative branch instructions have a 24 bit displacement field.
2296   As PPC code is always 4-byte-aligned, this yields a +-32MB range.
2297   If a particular imported symbol is outside this range, we have to redirect
2298   the jump to a short piece of new code that just loads the 32bit absolute
2299   address and jumps there.
2300   On x86_64, PC-relative jumps and PC-relative accesses to the GOT are limited
2301   to 32 bits (+-2GB).
2302
2303   This function just allocates space for one SymbolExtra for every
2304   undefined symbol in the object file. The code for the jump islands is
2305   filled in by makeSymbolExtra below.
2306 */
2307
2308 static int ocAllocateSymbolExtras( ObjectCode* oc, int count, int first )
2309 {
2310 #ifdef USE_MMAP
2311   int pagesize, n, m;
2312 #endif
2313   int aligned;
2314 #ifndef USE_MMAP
2315   int misalignment = 0;
2316 #ifdef darwin_HOST_OS
2317   misalignment = oc->misalignment;
2318 #endif
2319 #endif
2320
2321   if( count > 0 )
2322   {
2323     // round up to the nearest 4
2324     aligned = (oc->fileSize + 3) & ~3;
2325
2326 #ifdef USE_MMAP
2327     pagesize = getpagesize();
2328     n = ROUND_UP( oc->fileSize, pagesize );
2329     m = ROUND_UP( aligned + sizeof (SymbolExtra) * count, pagesize );
2330
2331     /* we try to use spare space at the end of the last page of the
2332      * image for the jump islands, but if there isn't enough space
2333      * then we have to map some (anonymously, remembering MAP_32BIT).
2334      */
2335     if( m > n ) // we need to allocate more pages
2336     {
2337         oc->symbol_extras = mmapForLinker(sizeof(SymbolExtra) * count,
2338                                           MAP_ANONYMOUS, -1);
2339     }
2340     else
2341     {
2342         oc->symbol_extras = (SymbolExtra *) (oc->image + aligned);
2343     }
2344 #else
2345     oc->image -= misalignment;
2346     oc->image = stgReallocBytes( oc->image,
2347                                  misalignment +
2348                                  aligned + sizeof (SymbolExtra) * count,
2349                                  "ocAllocateSymbolExtras" );
2350     oc->image += misalignment;
2351
2352     oc->symbol_extras = (SymbolExtra *) (oc->image + aligned);
2353 #endif /* USE_MMAP */
2354
2355     memset( oc->symbol_extras, 0, sizeof (SymbolExtra) * count );
2356   }
2357   else
2358     oc->symbol_extras = NULL;
2359
2360   oc->first_symbol_extra = first;
2361   oc->n_symbol_extras = count;
2362
2363   return 1;
2364 }
2365
2366 static SymbolExtra* makeSymbolExtra( ObjectCode* oc,
2367                                      unsigned long symbolNumber,
2368                                      unsigned long target )
2369 {
2370   SymbolExtra *extra;
2371
2372   ASSERT( symbolNumber >= oc->first_symbol_extra
2373         && symbolNumber - oc->first_symbol_extra < oc->n_symbol_extras);
2374
2375   extra = &oc->symbol_extras[symbolNumber - oc->first_symbol_extra];
2376
2377 #ifdef powerpc_HOST_ARCH
2378   // lis r12, hi16(target)
2379   extra->jumpIsland.lis_r12     = 0x3d80;
2380   extra->jumpIsland.hi_addr     = target >> 16;
2381
2382   // ori r12, r12, lo16(target)
2383   extra->jumpIsland.ori_r12_r12 = 0x618c;
2384   extra->jumpIsland.lo_addr     = target & 0xffff;
2385
2386   // mtctr r12
2387   extra->jumpIsland.mtctr_r12   = 0x7d8903a6;
2388
2389   // bctr
2390   extra->jumpIsland.bctr        = 0x4e800420;
2391 #endif
2392 #ifdef x86_64_HOST_ARCH
2393         // jmp *-14(%rip)
2394   static uint8_t jmp[] = { 0xFF, 0x25, 0xF2, 0xFF, 0xFF, 0xFF };
2395   extra->addr = target;
2396   memcpy(extra->jumpIsland, jmp, 6);
2397 #endif
2398
2399   return extra;
2400 }
2401
2402 #endif
2403
2404 /* --------------------------------------------------------------------------
2405  * PowerPC specifics (instruction cache flushing)
2406  * ------------------------------------------------------------------------*/
2407
2408 #ifdef powerpc_HOST_ARCH
2409 /*
2410    ocFlushInstructionCache
2411
2412    Flush the data & instruction caches.
2413    Because the PPC has split data/instruction caches, we have to
2414    do that whenever we modify code at runtime.
2415  */
2416 static void ocFlushInstructionCacheFrom(void* begin, size_t length)
2417 {
2418     size_t         n = (length + 3) / 4;
2419     unsigned long* p = begin;
2420
2421     while (n--)
2422     {
2423         __asm__ volatile ( "dcbf 0,%0\n\t"
2424                            "sync\n\t"
2425                            "icbi 0,%0"
2426                            :
2427                            : "r" (p)
2428                          );
2429         p++;
2430     }
2431     __asm__ volatile ( "sync\n\t"
2432                        "isync"
2433                      );
2434 }
2435 static void ocFlushInstructionCache( ObjectCode *oc )
2436 {
2437     /* The main object code */
2438     ocFlushInstructionCacheFrom(oc->image + oc->misalignment, oc->fileSize);
2439
2440     /* Jump Islands */
2441     ocFlushInstructionCacheFrom(oc->symbol_extras, sizeof(SymbolExtra) * oc->n_symbol_extras);
2442 }
2443 #endif
2444
2445 /* --------------------------------------------------------------------------
2446  * PEi386 specifics (Win32 targets)
2447  * ------------------------------------------------------------------------*/
2448
2449 /* The information for this linker comes from
2450       Microsoft Portable Executable
2451       and Common Object File Format Specification
2452       revision 5.1 January 1998
2453    which SimonM says comes from the MS Developer Network CDs.
2454
2455    It can be found there (on older CDs), but can also be found
2456    online at:
2457
2458       http://www.microsoft.com/hwdev/hardware/PECOFF.asp
2459
2460    (this is Rev 6.0 from February 1999).
2461
2462    Things move, so if that fails, try searching for it via
2463
2464       http://www.google.com/search?q=PE+COFF+specification
2465
2466    The ultimate reference for the PE format is the Winnt.h
2467    header file that comes with the Platform SDKs; as always,
2468    implementations will drift wrt their documentation.
2469
2470    A good background article on the PE format is Matt Pietrek's
2471    March 1994 article in Microsoft System Journal (MSJ)
2472    (Vol.9, No. 3): "Peering Inside the PE: A Tour of the
2473    Win32 Portable Executable File Format." The info in there
2474    has recently been updated in a two part article in
2475    MSDN magazine, issues Feb and March 2002,
2476    "Inside Windows: An In-Depth Look into the Win32 Portable
2477    Executable File Format"
2478
2479    John Levine's book "Linkers and Loaders" contains useful
2480    info on PE too.
2481 */
2482
2483
2484 #if defined(OBJFORMAT_PEi386)
2485
2486
2487
2488 typedef unsigned char  UChar;
2489 typedef unsigned short UInt16;
2490 typedef unsigned int   UInt32;
2491 typedef          int   Int32;
2492
2493
2494 typedef
2495    struct {
2496       UInt16 Machine;
2497       UInt16 NumberOfSections;
2498       UInt32 TimeDateStamp;
2499       UInt32 PointerToSymbolTable;
2500       UInt32 NumberOfSymbols;
2501       UInt16 SizeOfOptionalHeader;
2502       UInt16 Characteristics;
2503    }
2504    COFF_header;
2505
2506 #define sizeof_COFF_header 20
2507
2508
2509 typedef
2510    struct {
2511       UChar  Name[8];
2512       UInt32 VirtualSize;
2513       UInt32 VirtualAddress;
2514       UInt32 SizeOfRawData;
2515       UInt32 PointerToRawData;
2516       UInt32 PointerToRelocations;
2517       UInt32 PointerToLinenumbers;
2518       UInt16 NumberOfRelocations;
2519       UInt16 NumberOfLineNumbers;
2520       UInt32 Characteristics;
2521    }
2522    COFF_section;
2523
2524 #define sizeof_COFF_section 40
2525
2526
2527 typedef
2528    struct {
2529       UChar  Name[8];
2530       UInt32 Value;
2531       UInt16 SectionNumber;
2532       UInt16 Type;
2533       UChar  StorageClass;
2534       UChar  NumberOfAuxSymbols;
2535    }
2536    COFF_symbol;
2537
2538 #define sizeof_COFF_symbol 18
2539
2540
2541 typedef
2542    struct {
2543       UInt32 VirtualAddress;
2544       UInt32 SymbolTableIndex;
2545       UInt16 Type;
2546    }
2547    COFF_reloc;
2548
2549 #define sizeof_COFF_reloc 10
2550
2551
2552 /* From PE spec doc, section 3.3.2 */
2553 /* Note use of MYIMAGE_* since IMAGE_* are already defined in
2554    windows.h -- for the same purpose, but I want to know what I'm
2555    getting, here. */
2556 #define MYIMAGE_FILE_RELOCS_STRIPPED     0x0001
2557 #define MYIMAGE_FILE_EXECUTABLE_IMAGE    0x0002
2558 #define MYIMAGE_FILE_DLL                 0x2000
2559 #define MYIMAGE_FILE_SYSTEM              0x1000
2560 #define MYIMAGE_FILE_BYTES_REVERSED_HI   0x8000
2561 #define MYIMAGE_FILE_BYTES_REVERSED_LO   0x0080
2562 #define MYIMAGE_FILE_32BIT_MACHINE       0x0100
2563
2564 /* From PE spec doc, section 5.4.2 and 5.4.4 */
2565 #define MYIMAGE_SYM_CLASS_EXTERNAL       2
2566 #define MYIMAGE_SYM_CLASS_STATIC         3
2567 #define MYIMAGE_SYM_UNDEFINED            0
2568
2569 /* From PE spec doc, section 4.1 */
2570 #define MYIMAGE_SCN_CNT_CODE             0x00000020
2571 #define MYIMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040
2572 #define MYIMAGE_SCN_LNK_NRELOC_OVFL      0x01000000
2573
2574 /* From PE spec doc, section 5.2.1 */
2575 #define MYIMAGE_REL_I386_DIR32           0x0006
2576 #define MYIMAGE_REL_I386_REL32           0x0014
2577
2578
2579 /* We use myindex to calculate array addresses, rather than
2580    simply doing the normal subscript thing.  That's because
2581    some of the above structs have sizes which are not
2582    a whole number of words.  GCC rounds their sizes up to a
2583    whole number of words, which means that the address calcs
2584    arising from using normal C indexing or pointer arithmetic
2585    are just plain wrong.  Sigh.
2586 */
2587 static UChar *
2588 myindex ( int scale, void* base, int index )
2589 {
2590    return
2591       ((UChar*)base) + scale * index;
2592 }
2593
2594
2595 static void
2596 printName ( UChar* name, UChar* strtab )
2597 {
2598    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
2599       UInt32 strtab_offset = * (UInt32*)(name+4);
2600       debugBelch("%s", strtab + strtab_offset );
2601    } else {
2602       int i;
2603       for (i = 0; i < 8; i++) {
2604          if (name[i] == 0) break;
2605          debugBelch("%c", name[i] );
2606       }
2607    }
2608 }
2609
2610
2611 static void
2612 copyName ( UChar* name, UChar* strtab, UChar* dst, int dstSize )
2613 {
2614    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
2615       UInt32 strtab_offset = * (UInt32*)(name+4);
2616       strncpy ( (char*)dst, (char*)strtab+strtab_offset, dstSize );
2617       dst[dstSize-1] = 0;
2618    } else {
2619       int i = 0;
2620       while (1) {
2621          if (i >= 8) break;
2622          if (name[i] == 0) break;
2623          dst[i] = name[i];
2624          i++;
2625       }
2626       dst[i] = 0;
2627    }
2628 }
2629
2630
2631 static UChar *
2632 cstring_from_COFF_symbol_name ( UChar* name, UChar* strtab )
2633 {
2634    UChar* newstr;
2635    /* If the string is longer than 8 bytes, look in the
2636       string table for it -- this will be correctly zero terminated.
2637    */
2638    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
2639       UInt32 strtab_offset = * (UInt32*)(name+4);
2640       return ((UChar*)strtab) + strtab_offset;
2641    }
2642    /* Otherwise, if shorter than 8 bytes, return the original,
2643       which by defn is correctly terminated.
2644    */
2645    if (name[7]==0) return name;
2646    /* The annoying case: 8 bytes.  Copy into a temporary
2647       (XXX which is never freed ...)
2648    */
2649    newstr = stgMallocBytes(9, "cstring_from_COFF_symbol_name");
2650    ASSERT(newstr);
2651    strncpy((char*)newstr,(char*)name,8);
2652    newstr[8] = 0;
2653    return newstr;
2654 }
2655
2656 /* Getting the name of a section is mildly tricky, so we make a
2657    function for it.  Sadly, in one case we have to copy the string
2658    (when it is exactly 8 bytes long there's no trailing '\0'), so for
2659    consistency we *always* copy the string; the caller must free it
2660 */
2661 static char *
2662 cstring_from_section_name (UChar* name, UChar* strtab)
2663 {
2664     char *newstr;
2665
2666     if (name[0]=='/') {
2667         int strtab_offset = strtol((char*)name+1,NULL,10);
2668         int len = strlen(((char*)strtab) + strtab_offset);
2669
2670         newstr = stgMallocBytes(len, "cstring_from_section_symbol_name");
2671         strcpy((char*)newstr, (char*)((UChar*)strtab) + strtab_offset);
2672         return newstr;
2673     }
2674     else
2675     {
2676         newstr = stgMallocBytes(9, "cstring_from_section_symbol_name");
2677         ASSERT(newstr);
2678         strncpy((char*)newstr,(char*)name,8);
2679         newstr[8] = 0;
2680         return newstr;
2681     }
2682 }
2683
2684 /* Just compares the short names (first 8 chars) */
2685 static COFF_section *
2686 findPEi386SectionCalled ( ObjectCode* oc,  UChar* name )
2687 {
2688    int i;
2689    COFF_header* hdr
2690       = (COFF_header*)(oc->image);
2691    COFF_section* sectab
2692       = (COFF_section*) (
2693            ((UChar*)(oc->image))
2694            + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2695         );
2696    for (i = 0; i < hdr->NumberOfSections; i++) {
2697       UChar* n1;
2698       UChar* n2;
2699       COFF_section* section_i
2700          = (COFF_section*)
2701            myindex ( sizeof_COFF_section, sectab, i );
2702       n1 = (UChar*) &(section_i->Name);
2703       n2 = name;
2704       if (n1[0]==n2[0] && n1[1]==n2[1] && n1[2]==n2[2] &&
2705           n1[3]==n2[3] && n1[4]==n2[4] && n1[5]==n2[5] &&
2706           n1[6]==n2[6] && n1[7]==n2[7])
2707          return section_i;
2708    }
2709
2710    return NULL;
2711 }
2712
2713
2714 static void
2715 zapTrailingAtSign ( UChar* sym )
2716 {
2717 #  define my_isdigit(c) ((c) >= '0' && (c) <= '9')
2718    int i, j;
2719    if (sym[0] == 0) return;
2720    i = 0;
2721    while (sym[i] != 0) i++;
2722    i--;
2723    j = i;
2724    while (j > 0 && my_isdigit(sym[j])) j--;
2725    if (j > 0 && sym[j] == '@' && j != i) sym[j] = 0;
2726 #  undef my_isdigit
2727 }
2728
2729 static void *
2730 lookupSymbolInDLLs ( UChar *lbl )
2731 {
2732     OpenedDLL* o_dll;
2733     void *sym;
2734
2735     for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
2736         /* debugBelch("look in %s for %s\n", o_dll->name, lbl); */
2737
2738         if (lbl[0] == '_') {
2739             /* HACK: if the name has an initial underscore, try stripping
2740                it off & look that up first. I've yet to verify whether there's
2741                a Rule that governs whether an initial '_' *should always* be
2742                stripped off when mapping from import lib name to the DLL name.
2743             */
2744             sym = GetProcAddress(o_dll->instance, (char*)(lbl+1));
2745             if (sym != NULL) {
2746                 /*debugBelch("found %s in %s\n", lbl+1,o_dll->name);*/
2747                 return sym;
2748             }
2749         }
2750         sym = GetProcAddress(o_dll->instance, (char*)lbl);
2751         if (sym != NULL) {
2752             /*debugBelch("found %s in %s\n", lbl,o_dll->name);*/
2753             return sym;
2754            }
2755     }
2756     return NULL;
2757 }
2758
2759
2760 static int
2761 ocVerifyImage_PEi386 ( ObjectCode* oc )
2762 {
2763    int i;
2764    UInt32 j, noRelocs;
2765    COFF_header*  hdr;
2766    COFF_section* sectab;
2767    COFF_symbol*  symtab;
2768    UChar*        strtab;
2769    /* debugBelch("\nLOADING %s\n", oc->fileName); */
2770    hdr = (COFF_header*)(oc->image);
2771    sectab = (COFF_section*) (
2772                ((UChar*)(oc->image))
2773                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2774             );
2775    symtab = (COFF_symbol*) (
2776                ((UChar*)(oc->image))
2777                + hdr->PointerToSymbolTable
2778             );
2779    strtab = ((UChar*)symtab)
2780             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2781
2782    if (hdr->Machine != 0x14c) {
2783       errorBelch("%s: Not x86 PEi386", oc->fileName);
2784       return 0;
2785    }
2786    if (hdr->SizeOfOptionalHeader != 0) {
2787       errorBelch("%s: PEi386 with nonempty optional header", oc->fileName);
2788       return 0;
2789    }
2790    if ( /* (hdr->Characteristics & MYIMAGE_FILE_RELOCS_STRIPPED) || */
2791         (hdr->Characteristics & MYIMAGE_FILE_EXECUTABLE_IMAGE) ||
2792         (hdr->Characteristics & MYIMAGE_FILE_DLL) ||
2793         (hdr->Characteristics & MYIMAGE_FILE_SYSTEM) ) {
2794       errorBelch("%s: Not a PEi386 object file", oc->fileName);
2795       return 0;
2796    }
2797    if ( (hdr->Characteristics & MYIMAGE_FILE_BYTES_REVERSED_HI)
2798         /* || !(hdr->Characteristics & MYIMAGE_FILE_32BIT_MACHINE) */ ) {
2799       errorBelch("%s: Invalid PEi386 word size or endiannness: %d",
2800                  oc->fileName,
2801                  (int)(hdr->Characteristics));
2802       return 0;
2803    }
2804    /* If the string table size is way crazy, this might indicate that
2805       there are more than 64k relocations, despite claims to the
2806       contrary.  Hence this test. */
2807    /* debugBelch("strtab size %d\n", * (UInt32*)strtab); */
2808 #if 0
2809    if ( (*(UInt32*)strtab) > 600000 ) {
2810       /* Note that 600k has no special significance other than being
2811          big enough to handle the almost-2MB-sized lumps that
2812          constitute HSwin32*.o. */
2813       debugBelch("PEi386 object has suspiciously large string table; > 64k relocs?");
2814       return 0;
2815    }
2816 #endif
2817
2818    /* No further verification after this point; only debug printing. */
2819    i = 0;
2820    IF_DEBUG(linker, i=1);
2821    if (i == 0) return 1;
2822
2823    debugBelch( "sectab offset = %d\n", ((UChar*)sectab) - ((UChar*)hdr) );
2824    debugBelch( "symtab offset = %d\n", ((UChar*)symtab) - ((UChar*)hdr) );
2825    debugBelch( "strtab offset = %d\n", ((UChar*)strtab) - ((UChar*)hdr) );
2826
2827    debugBelch("\n" );
2828    debugBelch( "Machine:           0x%x\n", (UInt32)(hdr->Machine) );
2829    debugBelch( "# sections:        %d\n",   (UInt32)(hdr->NumberOfSections) );
2830    debugBelch( "time/date:         0x%x\n", (UInt32)(hdr->TimeDateStamp) );
2831    debugBelch( "symtab offset:     %d\n",   (UInt32)(hdr->PointerToSymbolTable) );
2832    debugBelch( "# symbols:         %d\n",   (UInt32)(hdr->NumberOfSymbols) );
2833    debugBelch( "sz of opt hdr:     %d\n",   (UInt32)(hdr->SizeOfOptionalHeader) );
2834    debugBelch( "characteristics:   0x%x\n", (UInt32)(hdr->Characteristics) );
2835
2836    /* Print the section table. */
2837    debugBelch("\n" );
2838    for (i = 0; i < hdr->NumberOfSections; i++) {
2839       COFF_reloc* reltab;
2840       COFF_section* sectab_i
2841          = (COFF_section*)
2842            myindex ( sizeof_COFF_section, sectab, i );
2843       debugBelch(
2844                 "\n"
2845                 "section %d\n"
2846                 "     name `",
2847                 i
2848               );
2849       printName ( sectab_i->Name, strtab );
2850       debugBelch(
2851                 "'\n"
2852                 "    vsize %d\n"
2853                 "    vaddr %d\n"
2854                 "  data sz %d\n"
2855                 " data off %d\n"
2856                 "  num rel %d\n"
2857                 "  off rel %d\n"
2858                 "  ptr raw 0x%x\n",
2859                 sectab_i->VirtualSize,
2860                 sectab_i->VirtualAddress,
2861                 sectab_i->SizeOfRawData,
2862                 sectab_i->PointerToRawData,
2863                 sectab_i->NumberOfRelocations,
2864                 sectab_i->PointerToRelocations,
2865                 sectab_i->PointerToRawData
2866               );
2867       reltab = (COFF_reloc*) (
2868                   ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2869                );
2870
2871       if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2872         /* If the relocation field (a short) has overflowed, the
2873          * real count can be found in the first reloc entry.
2874          *
2875          * See Section 4.1 (last para) of the PE spec (rev6.0).
2876          */
2877         COFF_reloc* rel = (COFF_reloc*)
2878                            myindex ( sizeof_COFF_reloc, reltab, 0 );
2879         noRelocs = rel->VirtualAddress;
2880         j = 1;
2881       } else {
2882         noRelocs = sectab_i->NumberOfRelocations;
2883         j = 0;
2884       }
2885
2886       for (; j < noRelocs; j++) {
2887          COFF_symbol* sym;
2888          COFF_reloc* rel = (COFF_reloc*)
2889                            myindex ( sizeof_COFF_reloc, reltab, j );
2890          debugBelch(
2891                    "        type 0x%-4x   vaddr 0x%-8x   name `",
2892                    (UInt32)rel->Type,
2893                    rel->VirtualAddress );
2894          sym = (COFF_symbol*)
2895                myindex ( sizeof_COFF_symbol, symtab, rel->SymbolTableIndex );
2896          /* Hmm..mysterious looking offset - what's it for? SOF */
2897          printName ( sym->Name, strtab -10 );
2898          debugBelch("'\n" );
2899       }
2900
2901       debugBelch("\n" );
2902    }
2903    debugBelch("\n" );
2904    debugBelch("string table has size 0x%x\n", * (UInt32*)strtab );
2905    debugBelch("---START of string table---\n");
2906    for (i = 4; i < *(Int32*)strtab; i++) {
2907       if (strtab[i] == 0)
2908          debugBelch("\n"); else
2909          debugBelch("%c", strtab[i] );
2910    }
2911    debugBelch("--- END  of string table---\n");
2912
2913    debugBelch("\n" );
2914    i = 0;
2915    while (1) {
2916       COFF_symbol* symtab_i;
2917       if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2918       symtab_i = (COFF_symbol*)
2919                  myindex ( sizeof_COFF_symbol, symtab, i );
2920       debugBelch(
2921                 "symbol %d\n"
2922                 "     name `",
2923                 i
2924               );
2925       printName ( symtab_i->Name, strtab );
2926       debugBelch(
2927                 "'\n"
2928                 "    value 0x%x\n"
2929                 "   1+sec# %d\n"
2930                 "     type 0x%x\n"
2931                 "   sclass 0x%x\n"
2932                 "     nAux %d\n",
2933                 symtab_i->Value,
2934                 (Int32)(symtab_i->SectionNumber),
2935                 (UInt32)symtab_i->Type,
2936                 (UInt32)symtab_i->StorageClass,
2937                 (UInt32)symtab_i->NumberOfAuxSymbols
2938               );
2939       i += symtab_i->NumberOfAuxSymbols;
2940       i++;
2941    }
2942
2943    debugBelch("\n" );
2944    return 1;
2945 }
2946
2947
2948 static int
2949 ocGetNames_PEi386 ( ObjectCode* oc )
2950 {
2951    COFF_header*  hdr;
2952    COFF_section* sectab;
2953    COFF_symbol*  symtab;
2954    UChar*        strtab;
2955
2956    UChar* sname;
2957    void*  addr;
2958    int    i;
2959
2960    hdr = (COFF_header*)(oc->image);
2961    sectab = (COFF_section*) (
2962                ((UChar*)(oc->image))
2963                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2964             );
2965    symtab = (COFF_symbol*) (
2966                ((UChar*)(oc->image))
2967                + hdr->PointerToSymbolTable
2968             );
2969    strtab = ((UChar*)(oc->image))
2970             + hdr->PointerToSymbolTable
2971             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2972
2973    /* Allocate space for any (local, anonymous) .bss sections. */
2974
2975    for (i = 0; i < hdr->NumberOfSections; i++) {
2976       UInt32 bss_sz;
2977       UChar* zspace;
2978       COFF_section* sectab_i
2979          = (COFF_section*)
2980            myindex ( sizeof_COFF_section, sectab, i );
2981
2982       char *secname = cstring_from_section_name(sectab_i->Name, strtab);
2983
2984       if (0 != strcmp(secname, ".bss")) {
2985           stgFree(secname);
2986           continue;
2987       }
2988
2989       stgFree(secname);
2990
2991       /* sof 10/05: the PE spec text isn't too clear regarding what
2992        * the SizeOfRawData field is supposed to hold for object
2993        * file sections containing just uninitialized data -- for executables,
2994        * it is supposed to be zero; unclear what it's supposed to be
2995        * for object files. However, VirtualSize is guaranteed to be
2996        * zero for object files, which definitely suggests that SizeOfRawData
2997        * will be non-zero (where else would the size of this .bss section be
2998        * stored?) Looking at the COFF_section info for incoming object files,
2999        * this certainly appears to be the case.
3000        *
3001        * => I suspect we've been incorrectly handling .bss sections in (relocatable)
3002        * object files up until now. This turned out to bite us with ghc-6.4.1's use
3003        * of gcc-3.4.x, which has started to emit initially-zeroed-out local 'static'
3004        * variable decls into to the .bss section. (The specific function in Q which
3005        * triggered this is libraries/base/cbits/dirUtils.c:__hscore_getFolderPath())
3006        */
3007       if (sectab_i->VirtualSize == 0 && sectab_i->SizeOfRawData == 0) continue;
3008       /* This is a non-empty .bss section.  Allocate zeroed space for
3009          it, and set its PointerToRawData field such that oc->image +
3010          PointerToRawData == addr_of_zeroed_space.  */
3011       bss_sz = sectab_i->VirtualSize;
3012       if ( bss_sz < sectab_i->SizeOfRawData) { bss_sz = sectab_i->SizeOfRawData; }
3013       zspace = stgCallocBytes(1, bss_sz, "ocGetNames_PEi386(anonymous bss)");
3014       sectab_i->PointerToRawData = ((UChar*)zspace) - ((UChar*)(oc->image));
3015       addProddableBlock(oc, zspace, bss_sz);
3016       /* debugBelch("BSS anon section at 0x%x\n", zspace); */
3017    }
3018
3019    /* Copy section information into the ObjectCode. */
3020
3021    for (i = 0; i < hdr->NumberOfSections; i++) {
3022       UChar* start;
3023       UChar* end;
3024       UInt32 sz;
3025
3026       SectionKind kind
3027          = SECTIONKIND_OTHER;
3028       COFF_section* sectab_i
3029          = (COFF_section*)
3030            myindex ( sizeof_COFF_section, sectab, i );
3031
3032       char *secname = cstring_from_section_name(sectab_i->Name, strtab);
3033
3034       IF_DEBUG(linker, debugBelch("section name = %s\n", secname ));
3035
3036 #     if 0
3037       /* I'm sure this is the Right Way to do it.  However, the
3038          alternative of testing the sectab_i->Name field seems to
3039          work ok with Cygwin.
3040       */
3041       if (sectab_i->Characteristics & MYIMAGE_SCN_CNT_CODE ||
3042           sectab_i->Characteristics & MYIMAGE_SCN_CNT_INITIALIZED_DATA)
3043          kind = SECTIONKIND_CODE_OR_RODATA;
3044 #     endif
3045
3046       if (0==strcmp(".text",(char*)secname) ||
3047           0==strcmp(".rdata",(char*)secname)||
3048           0==strcmp(".rodata",(char*)secname))
3049          kind = SECTIONKIND_CODE_OR_RODATA;
3050       if (0==strcmp(".data",(char*)secname) ||
3051           0==strcmp(".bss",(char*)secname))
3052          kind = SECTIONKIND_RWDATA;
3053
3054       ASSERT(sectab_i->SizeOfRawData == 0 || sectab_i->VirtualSize == 0);
3055       sz = sectab_i->SizeOfRawData;
3056       if (sz < sectab_i->VirtualSize) sz = sectab_i->VirtualSize;
3057
3058       start = ((UChar*)(oc->image)) + sectab_i->PointerToRawData;
3059       end   = start + sz - 1;
3060
3061       if (kind == SECTIONKIND_OTHER
3062           /* Ignore sections called which contain stabs debugging
3063              information. */
3064           && 0 != strcmp(".stab", (char*)secname)
3065           && 0 != strcmp(".stabstr", (char*)secname)
3066           /* ignore constructor section for now */
3067           && 0 != strcmp(".ctors", (char*)secname)
3068           /* ignore section generated from .ident */
3069           && 0!= strncmp(".debug", (char*)secname, 6)
3070           /* ignore unknown section that appeared in gcc 3.4.5(?) */
3071           && 0!= strcmp(".reloc", (char*)secname)
3072           && 0 != strcmp(".rdata$zzz", (char*)secname)
3073          ) {
3074          errorBelch("Unknown PEi386 section name `%s' (while processing: %s)", secname, oc->fileName);
3075          stgFree(secname);
3076          return 0;
3077       }
3078
3079       if (kind != SECTIONKIND_OTHER && end >= start) {
3080          addSection(oc, kind, start, end);
3081          addProddableBlock(oc, start, end - start + 1);
3082       }
3083
3084       stgFree(secname);
3085    }
3086
3087    /* Copy exported symbols into the ObjectCode. */
3088
3089    oc->n_symbols = hdr->NumberOfSymbols;
3090    oc->symbols   = stgMallocBytes(oc->n_symbols * sizeof(char*),
3091                                   "ocGetNames_PEi386(oc->symbols)");
3092    /* Call me paranoid; I don't care. */
3093    for (i = 0; i < oc->n_symbols; i++)
3094       oc->symbols[i] = NULL;
3095
3096    i = 0;
3097    while (1) {
3098       COFF_symbol* symtab_i;
3099       if (i >= (Int32)(hdr->NumberOfSymbols)) break;
3100       symtab_i = (COFF_symbol*)
3101                  myindex ( sizeof_COFF_symbol, symtab, i );
3102
3103       addr  = NULL;
3104
3105       if (symtab_i->StorageClass == MYIMAGE_SYM_CLASS_EXTERNAL
3106           && symtab_i->SectionNumber != MYIMAGE_SYM_UNDEFINED) {
3107          /* This symbol is global and defined, viz, exported */
3108          /* for MYIMAGE_SYMCLASS_EXTERNAL
3109                 && !MYIMAGE_SYM_UNDEFINED,
3110             the address of the symbol is:
3111                 address of relevant section + offset in section
3112          */
3113          COFF_section* sectabent
3114             = (COFF_section*) myindex ( sizeof_COFF_section,
3115                                         sectab,
3116                                         symtab_i->SectionNumber-1 );
3117          addr = ((UChar*)(oc->image))
3118                 + (sectabent->PointerToRawData
3119                    + symtab_i->Value);
3120       }
3121       else
3122       if (symtab_i->SectionNumber == MYIMAGE_SYM_UNDEFINED
3123           && symtab_i->Value > 0) {
3124          /* This symbol isn't in any section at all, ie, global bss.
3125             Allocate zeroed space for it. */
3126          addr = stgCallocBytes(1, symtab_i->Value,
3127                                "ocGetNames_PEi386(non-anonymous bss)");
3128          addSection(oc, SECTIONKIND_RWDATA, addr,
3129                         ((UChar*)addr) + symtab_i->Value - 1);
3130          addProddableBlock(oc, addr, symtab_i->Value);
3131          /* debugBelch("BSS      section at 0x%x\n", addr); */
3132       }
3133
3134       if (addr != NULL ) {
3135          sname = cstring_from_COFF_symbol_name ( symtab_i->Name, strtab );
3136          /* debugBelch("addSymbol %p `%s \n", addr,sname);  */
3137          IF_DEBUG(linker, debugBelch("addSymbol %p `%s'\n", addr,sname);)
3138          ASSERT(i >= 0 && i < oc->n_symbols);
3139          /* cstring_from_COFF_symbol_name always succeeds. */
3140          oc->symbols[i] = (char*)sname;
3141          ghciInsertStrHashTable(oc->fileName, symhash, (char*)sname, addr);
3142       } else {
3143 #        if 0
3144          debugBelch(
3145                    "IGNORING symbol %d\n"
3146                    "     name `",
3147                    i
3148                  );
3149          printName ( symtab_i->Name, strtab );
3150          debugBelch(
3151                    "'\n"
3152                    "    value 0x%x\n"
3153                    "   1+sec# %d\n"
3154                    "     type 0x%x\n"
3155                    "   sclass 0x%x\n"
3156                    "     nAux %d\n",
3157                    symtab_i->Value,
3158                    (Int32)(symtab_i->SectionNumber),
3159                    (UInt32)symtab_i->Type,
3160                    (UInt32)symtab_i->StorageClass,
3161                    (UInt32)symtab_i->NumberOfAuxSymbols
3162                  );
3163 #        endif
3164       }
3165
3166       i += symtab_i->NumberOfAuxSymbols;
3167       i++;
3168    }
3169
3170    return 1;
3171 }
3172
3173
3174 static int
3175 ocResolve_PEi386 ( ObjectCode* oc )
3176 {
3177    COFF_header*  hdr;
3178    COFF_section* sectab;
3179    COFF_symbol*  symtab;
3180    UChar*        strtab;
3181
3182    UInt32        A;
3183    UInt32        S;
3184    UInt32*       pP;
3185
3186    int i;
3187    UInt32 j, noRelocs;
3188
3189    /* ToDo: should be variable-sized?  But is at least safe in the
3190       sense of buffer-overrun-proof. */
3191    UChar symbol[1000];
3192    /* debugBelch("resolving for %s\n", oc->fileName); */
3193
3194    hdr = (COFF_header*)(oc->image);
3195    sectab = (COFF_section*) (
3196                ((UChar*)(oc->image))
3197                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
3198             );
3199    symtab = (COFF_symbol*) (
3200                ((UChar*)(oc->image))
3201                + hdr->PointerToSymbolTable
3202             );
3203    strtab = ((UChar*)(oc->image))
3204             + hdr->PointerToSymbolTable
3205             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
3206
3207    for (i = 0; i < hdr->NumberOfSections; i++) {
3208       COFF_section* sectab_i
3209          = (COFF_section*)
3210            myindex ( sizeof_COFF_section, sectab, i );
3211       COFF_reloc* reltab
3212          = (COFF_reloc*) (
3213               ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
3214            );
3215
3216       char *secname = cstring_from_section_name(sectab_i->Name, strtab);
3217
3218       /* Ignore sections called which contain stabs debugging
3219          information. */
3220       if (0 == strcmp(".stab", (char*)secname)
3221           || 0 == strcmp(".stabstr", (char*)secname)
3222           || 0 == strcmp(".ctors", (char*)secname)
3223           || 0 == strncmp(".debug", (char*)secname, 6)
3224           || 0 == strcmp(".rdata$zzz", (char*)secname)) {
3225           stgFree(secname);
3226           continue;
3227       }
3228
3229       stgFree(secname);
3230
3231       if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
3232         /* If the relocation field (a short) has overflowed, the
3233          * real count can be found in the first reloc entry.
3234          *
3235          * See Section 4.1 (last para) of the PE spec (rev6.0).
3236          *
3237          * Nov2003 update: the GNU linker still doesn't correctly
3238          * handle the generation of relocatable object files with
3239          * overflown relocations. Hence the output to warn of potential
3240          * troubles.
3241          */
3242         COFF_reloc* rel = (COFF_reloc*)
3243                            myindex ( sizeof_COFF_reloc, reltab, 0 );
3244         noRelocs = rel->VirtualAddress;
3245
3246         /* 10/05: we now assume (and check for) a GNU ld that is capable
3247          * of handling object files with (>2^16) of relocs.
3248          */
3249 #if 0
3250         debugBelch("WARNING: Overflown relocation field (# relocs found: %u)\n",
3251                    noRelocs);
3252 #endif
3253         j = 1;
3254       } else {
3255         noRelocs = sectab_i->NumberOfRelocations;
3256         j = 0;
3257       }
3258
3259
3260       for (; j < noRelocs; j++) {
3261          COFF_symbol* sym;
3262          COFF_reloc* reltab_j
3263             = (COFF_reloc*)
3264               myindex ( sizeof_COFF_reloc, reltab, j );
3265
3266          /* the location to patch */
3267          pP = (UInt32*)(
3268                  ((UChar*)(oc->image))
3269                  + (sectab_i->PointerToRawData
3270                     + reltab_j->VirtualAddress
3271                     - sectab_i->VirtualAddress )
3272               );
3273          /* the existing contents of pP */
3274          A = *pP;
3275          /* the symbol to connect to */
3276          sym = (COFF_symbol*)
3277                myindex ( sizeof_COFF_symbol,
3278                          symtab, reltab_j->SymbolTableIndex );
3279          IF_DEBUG(linker,
3280                   debugBelch(
3281                             "reloc sec %2d num %3d:  type 0x%-4x   "
3282                             "vaddr 0x%-8x   name `",
3283                             i, j,
3284                             (UInt32)reltab_j->Type,
3285                             reltab_j->VirtualAddress );
3286                             printName ( sym->Name, strtab );
3287                             debugBelch("'\n" ));
3288
3289          if (sym->StorageClass == MYIMAGE_SYM_CLASS_STATIC) {
3290             COFF_section* section_sym
3291                = findPEi386SectionCalled ( oc, sym->Name );
3292             if (!section_sym) {
3293                errorBelch("%s: can't find section `%s'", oc->fileName, sym->Name);
3294                return 0;
3295             }
3296             S = ((UInt32)(oc->image))
3297                 + (section_sym->PointerToRawData
3298                    + sym->Value);
3299          } else {
3300             copyName ( sym->Name, strtab, symbol, 1000-1 );
3301             S = (UInt32) lookupSymbol( (char*)symbol );
3302             if ((void*)S != NULL) goto foundit;
3303             errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3304             return 0;
3305            foundit:;
3306          }
3307          checkProddableBlock(oc, pP);
3308          switch (reltab_j->Type) {
3309             case MYIMAGE_REL_I386_DIR32:
3310                *pP = A + S;
3311                break;
3312             case MYIMAGE_REL_I386_REL32:
3313                /* Tricky.  We have to insert a displacement at
3314                   pP which, when added to the PC for the _next_
3315                   insn, gives the address of the target (S).
3316                   Problem is to know the address of the next insn
3317                   when we only know pP.  We assume that this
3318                   literal field is always the last in the insn,
3319                   so that the address of the next insn is pP+4
3320                   -- hence the constant 4.
3321                   Also I don't know if A should be added, but so
3322                   far it has always been zero.
3323
3324                   SOF 05/2005: 'A' (old contents of *pP) have been observed
3325                   to contain values other than zero (the 'wx' object file
3326                   that came with wxhaskell-0.9.4; dunno how it was compiled..).
3327                   So, add displacement to old value instead of asserting
3328                   A to be zero. Fixes wxhaskell-related crashes, and no other
3329                   ill effects have been observed.
3330
3331                   Update: the reason why we're seeing these more elaborate
3332                   relocations is due to a switch in how the NCG compiles SRTs
3333                   and offsets to them from info tables. SRTs live in .(ro)data,
3334                   while info tables live in .text, causing GAS to emit REL32/DISP32
3335                   relocations with non-zero values. Adding the displacement is
3336                   the right thing to do.
3337                */
3338                *pP = S - ((UInt32)pP) - 4 + A;
3339                break;
3340             default:
3341                debugBelch("%s: unhandled PEi386 relocation type %d",
3342                      oc->fileName, reltab_j->Type);
3343                return 0;
3344          }
3345
3346       }
3347    }
3348
3349    IF_DEBUG(linker, debugBelch("completed %s", oc->fileName));
3350    return 1;
3351 }
3352
3353 #endif /* defined(OBJFORMAT_PEi386) */
3354
3355
3356 /* --------------------------------------------------------------------------
3357  * ELF specifics
3358  * ------------------------------------------------------------------------*/
3359
3360 #if defined(OBJFORMAT_ELF)
3361
3362 #define FALSE 0
3363 #define TRUE  1
3364
3365 #if defined(sparc_HOST_ARCH)
3366 #  define ELF_TARGET_SPARC  /* Used inside <elf.h> */
3367 #elif defined(i386_HOST_ARCH)
3368 #  define ELF_TARGET_386    /* Used inside <elf.h> */
3369 #elif defined(x86_64_HOST_ARCH)
3370 #  define ELF_TARGET_X64_64
3371 #  define ELF_64BIT
3372 #endif
3373
3374 #if !defined(openbsd_HOST_OS)
3375 #  include <elf.h>
3376 #else
3377 /* openbsd elf has things in different places, with diff names */
3378 #  include <elf_abi.h>
3379 #  include <machine/reloc.h>
3380 #  define R_386_32    RELOC_32
3381 #  define R_386_PC32  RELOC_PC32
3382 #endif
3383
3384 /* If elf.h doesn't define it */
3385 #  ifndef R_X86_64_PC64
3386 #    define R_X86_64_PC64 24
3387 #  endif
3388
3389 /*
3390  * Define a set of types which can be used for both ELF32 and ELF64
3391  */
3392
3393 #ifdef ELF_64BIT
3394 #define ELFCLASS    ELFCLASS64
3395 #define Elf_Addr    Elf64_Addr
3396 #define Elf_Word    Elf64_Word
3397 #define Elf_Sword   Elf64_Sword
3398 #define Elf_Ehdr    Elf64_Ehdr
3399 #define Elf_Phdr    Elf64_Phdr
3400 #define Elf_Shdr    Elf64_Shdr
3401 #define Elf_Sym     Elf64_Sym
3402 #define Elf_Rel     Elf64_Rel
3403 #define Elf_Rela    Elf64_Rela
3404 #ifndef ELF_ST_TYPE
3405 #define ELF_ST_TYPE ELF64_ST_TYPE
3406 #endif
3407 #ifndef ELF_ST_BIND
3408 #define ELF_ST_BIND ELF64_ST_BIND
3409 #endif
3410 #ifndef ELF_R_TYPE
3411 #define ELF_R_TYPE  ELF64_R_TYPE
3412 #endif
3413 #ifndef ELF_R_SYM
3414 #define ELF_R_SYM   ELF64_R_SYM
3415 #endif
3416 #else
3417 #define ELFCLASS    ELFCLASS32
3418 #define Elf_Addr    Elf32_Addr
3419 #define Elf_Word    Elf32_Word
3420 #define Elf_Sword   Elf32_Sword
3421 #define Elf_Ehdr    Elf32_Ehdr
3422 #define Elf_Phdr    Elf32_Phdr
3423 #define Elf_Shdr    Elf32_Shdr
3424 #define Elf_Sym     Elf32_Sym
3425 #define Elf_Rel     Elf32_Rel
3426 #define Elf_Rela    Elf32_Rela
3427 #ifndef ELF_ST_TYPE
3428 #define ELF_ST_TYPE ELF32_ST_TYPE
3429 #endif
3430 #ifndef ELF_ST_BIND
3431 #define ELF_ST_BIND ELF32_ST_BIND
3432 #endif
3433 #ifndef ELF_R_TYPE
3434 #define ELF_R_TYPE  ELF32_R_TYPE
3435 #endif
3436 #ifndef ELF_R_SYM
3437 #define ELF_R_SYM   ELF32_R_SYM
3438 #endif
3439 #endif
3440
3441
3442 /*
3443  * Functions to allocate entries in dynamic sections.  Currently we simply
3444  * preallocate a large number, and we don't check if a entry for the given
3445  * target already exists (a linear search is too slow).  Ideally these
3446  * entries would be associated with symbols.
3447  */
3448
3449 /* These sizes sufficient to load HSbase + HShaskell98 + a few modules */
3450 #define GOT_SIZE            0x20000
3451 #define FUNCTION_TABLE_SIZE 0x10000
3452 #define PLT_SIZE            0x08000
3453
3454 #ifdef ELF_NEED_GOT
3455 static Elf_Addr got[GOT_SIZE];
3456 static unsigned int gotIndex;
3457 static Elf_Addr gp_val = (Elf_Addr)got;
3458
3459 static Elf_Addr
3460 allocateGOTEntry(Elf_Addr target)
3461 {
3462    Elf_Addr *entry;
3463
3464    if (gotIndex >= GOT_SIZE)
3465       barf("Global offset table overflow");
3466
3467    entry = &got[gotIndex++];
3468    *entry = target;
3469    return (Elf_Addr)entry;
3470 }
3471 #endif
3472
3473 #ifdef ELF_FUNCTION_DESC
3474 typedef struct {
3475    Elf_Addr ip;
3476    Elf_Addr gp;
3477 } FunctionDesc;
3478
3479 static FunctionDesc functionTable[FUNCTION_TABLE_SIZE];
3480 static unsigned int functionTableIndex;
3481
3482 static Elf_Addr
3483 allocateFunctionDesc(Elf_Addr target)
3484 {
3485    FunctionDesc *entry;
3486
3487    if (functionTableIndex >= FUNCTION_TABLE_SIZE)
3488       barf("Function table overflow");
3489
3490    entry = &functionTable[functionTableIndex++];
3491    entry->ip = target;
3492    entry->gp = (Elf_Addr)gp_val;
3493    return (Elf_Addr)entry;
3494 }
3495
3496 static Elf_Addr
3497 copyFunctionDesc(Elf_Addr target)
3498 {
3499    FunctionDesc *olddesc = (FunctionDesc *)target;
3500    FunctionDesc *newdesc;
3501
3502    newdesc = (FunctionDesc *)allocateFunctionDesc(olddesc->ip);
3503    newdesc->gp = olddesc->gp;
3504    return (Elf_Addr)newdesc;
3505 }
3506 #endif
3507
3508 #ifdef ELF_NEED_PLT
3509
3510 typedef struct {
3511    unsigned char code[sizeof(plt_code)];
3512 } PLTEntry;
3513
3514 static Elf_Addr
3515 allocatePLTEntry(Elf_Addr target, ObjectCode *oc)
3516 {
3517    PLTEntry *plt = (PLTEntry *)oc->plt;
3518    PLTEntry *entry;
3519
3520    if (oc->pltIndex >= PLT_SIZE)
3521       barf("Procedure table overflow");
3522
3523    entry = &plt[oc->pltIndex++];
3524    memcpy(entry->code, plt_code, sizeof(entry->code));
3525    PLT_RELOC(entry->code, target);
3526    return (Elf_Addr)entry;
3527 }
3528
3529 static unsigned int
3530 PLTSize(void)
3531 {
3532    return (PLT_SIZE * sizeof(PLTEntry));
3533 }
3534 #endif
3535
3536
3537 /*
3538  * Generic ELF functions
3539  */
3540
3541 static char *
3542 findElfSection ( void* objImage, Elf_Word sh_type )
3543 {
3544    char* ehdrC = (char*)objImage;
3545    Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
3546    Elf_Shdr* shdr = (Elf_Shdr*)(ehdrC + ehdr->e_shoff);
3547    char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
3548    char* ptr = NULL;
3549    int i;
3550
3551    for (i = 0; i < ehdr->e_shnum; i++) {
3552       if (shdr[i].sh_type == sh_type
3553           /* Ignore the section header's string table. */
3554           && i != ehdr->e_shstrndx
3555           /* Ignore string tables named .stabstr, as they contain
3556              debugging info. */
3557           && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
3558          ) {
3559          ptr = ehdrC + shdr[i].sh_offset;
3560          break;
3561       }
3562    }
3563    return ptr;
3564 }
3565
3566 static int
3567 ocVerifyImage_ELF ( ObjectCode* oc )
3568 {
3569    Elf_Shdr* shdr;
3570    Elf_Sym*  stab;
3571    int i, j, nent, nstrtab, nsymtabs;
3572    char* sh_strtab;
3573    char* strtab;
3574
3575    char*     ehdrC = (char*)(oc->image);
3576    Elf_Ehdr* ehdr  = (Elf_Ehdr*)ehdrC;
3577
3578    if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
3579        ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
3580        ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
3581        ehdr->e_ident[EI_MAG3] != ELFMAG3) {
3582       errorBelch("%s: not an ELF object", oc->fileName);
3583       return 0;
3584    }
3585
3586    if (ehdr->e_ident[EI_CLASS] != ELFCLASS) {
3587       errorBelch("%s: unsupported ELF format", oc->fileName);
3588       return 0;
3589    }
3590
3591    if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) {
3592        IF_DEBUG(linker,debugBelch( "Is little-endian\n" ));
3593    } else
3594    if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) {
3595        IF_DEBUG(linker,debugBelch( "Is big-endian\n" ));
3596    } else {
3597        errorBelch("%s: unknown endiannness", oc->fileName);
3598        return 0;
3599    }
3600
3601    if (ehdr->e_type != ET_REL) {
3602       errorBelch("%s: not a relocatable object (.o) file", oc->fileName);
3603       return 0;
3604    }
3605    IF_DEBUG(linker, debugBelch( "Is a relocatable object (.o) file\n" ));
3606
3607    IF_DEBUG(linker,debugBelch( "Architecture is " ));
3608    switch (ehdr->e_machine) {
3609       case EM_386:   IF_DEBUG(linker,debugBelch( "x86" )); break;
3610 #ifdef EM_SPARC32PLUS
3611       case EM_SPARC32PLUS:
3612 #endif
3613       case EM_SPARC: IF_DEBUG(linker,debugBelch( "sparc" )); break;
3614 #ifdef EM_IA_64
3615       case EM_IA_64: IF_DEBUG(linker,debugBelch( "ia64" )); break;
3616 #endif
3617       case EM_PPC:   IF_DEBUG(linker,debugBelch( "powerpc32" )); break;
3618 #ifdef EM_X86_64
3619       case EM_X86_64: IF_DEBUG(linker,debugBelch( "x86_64" )); break;
3620 #elif defined(EM_AMD64)
3621       case EM_AMD64: IF_DEBUG(linker,debugBelch( "amd64" )); break;
3622 #endif
3623       default:       IF_DEBUG(linker,debugBelch( "unknown" ));
3624                      errorBelch("%s: unknown architecture (e_machine == %d)"
3625                                 , oc->fileName, ehdr->e_machine);
3626                      return 0;
3627    }
3628
3629    IF_DEBUG(linker,debugBelch(
3630              "\nSection header table: start %ld, n_entries %d, ent_size %d\n",
3631              (long)ehdr->e_shoff, ehdr->e_shnum, ehdr->e_shentsize  ));
3632
3633    ASSERT (ehdr->e_shentsize == sizeof(Elf_Shdr));
3634
3635    shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3636
3637    if (ehdr->e_shstrndx == SHN_UNDEF) {
3638       errorBelch("%s: no section header string table", oc->fileName);
3639       return 0;
3640    } else {
3641       IF_DEBUG(linker,debugBelch( "Section header string table is section %d\n",
3642                           ehdr->e_shstrndx));
3643       sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
3644    }
3645
3646    for (i = 0; i < ehdr->e_shnum; i++) {
3647       IF_DEBUG(linker,debugBelch("%2d:  ", i ));
3648       IF_DEBUG(linker,debugBelch("type=%2d  ", (int)shdr[i].sh_type ));
3649       IF_DEBUG(linker,debugBelch("size=%4d  ", (int)shdr[i].sh_size ));
3650       IF_DEBUG(linker,debugBelch("offs=%4d  ", (int)shdr[i].sh_offset ));
3651       IF_DEBUG(linker,debugBelch("  (%p .. %p)  ",
3652                ehdrC + shdr[i].sh_offset,
3653                       ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1));
3654
3655       if (shdr[i].sh_type == SHT_REL) {
3656           IF_DEBUG(linker,debugBelch("Rel  " ));
3657       } else if (shdr[i].sh_type == SHT_RELA) {
3658           IF_DEBUG(linker,debugBelch("RelA " ));
3659       } else {
3660           IF_DEBUG(linker,debugBelch("     "));
3661       }
3662       if (sh_strtab) {
3663           IF_DEBUG(linker,debugBelch("sname=%s\n", sh_strtab + shdr[i].sh_name ));
3664       }
3665    }
3666
3667    IF_DEBUG(linker,debugBelch( "\nString tables" ));
3668    strtab = NULL;
3669    nstrtab = 0;
3670    for (i = 0; i < ehdr->e_shnum; i++) {
3671       if (shdr[i].sh_type == SHT_STRTAB
3672           /* Ignore the section header's string table. */
3673           && i != ehdr->e_shstrndx
3674           /* Ignore string tables named .stabstr, as they contain
3675              debugging info. */
3676           && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
3677          ) {
3678          IF_DEBUG(linker,debugBelch("   section %d is a normal string table", i ));
3679          strtab = ehdrC + shdr[i].sh_offset;
3680          nstrtab++;
3681       }
3682    }
3683    if (nstrtab != 1) {
3684       errorBelch("%s: no string tables, or too many", oc->fileName);
3685       return 0;
3686    }
3687
3688    nsymtabs = 0;
3689    IF_DEBUG(linker,debugBelch( "\nSymbol tables" ));
3690    for (i = 0; i < ehdr->e_shnum; i++) {
3691       if (shdr[i].sh_type != SHT_SYMTAB) continue;
3692       IF_DEBUG(linker,debugBelch( "section %d is a symbol table\n", i ));
3693       nsymtabs++;
3694       stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
3695       nent = shdr[i].sh_size / sizeof(Elf_Sym);
3696       IF_DEBUG(linker,debugBelch( "   number of entries is apparently %d (%ld rem)\n",
3697                nent,
3698                (long)shdr[i].sh_size % sizeof(Elf_Sym)
3699              ));
3700       if (0 != shdr[i].sh_size % sizeof(Elf_Sym)) {
3701          errorBelch("%s: non-integral number of symbol table entries", oc->fileName);
3702          return 0;
3703       }
3704       for (j = 0; j < nent; j++) {
3705          IF_DEBUG(linker,debugBelch("   %2d  ", j ));
3706          IF_DEBUG(linker,debugBelch("  sec=%-5d  size=%-3d  val=%5p  ",
3707                              (int)stab[j].st_shndx,
3708                              (int)stab[j].st_size,
3709                              (char*)stab[j].st_value ));
3710
3711          IF_DEBUG(linker,debugBelch("type=" ));
3712          switch (ELF_ST_TYPE(stab[j].st_info)) {
3713             case STT_NOTYPE:  IF_DEBUG(linker,debugBelch("notype " )); break;
3714             case STT_OBJECT:  IF_DEBUG(linker,debugBelch("object " )); break;
3715             case STT_FUNC  :  IF_DEBUG(linker,debugBelch("func   " )); break;
3716             case STT_SECTION: IF_DEBUG(linker,debugBelch("section" )); break;
3717             case STT_FILE:    IF_DEBUG(linker,debugBelch("file   " )); break;
3718             default:          IF_DEBUG(linker,debugBelch("?      " )); break;
3719          }
3720          IF_DEBUG(linker,debugBelch("  " ));
3721
3722          IF_DEBUG(linker,debugBelch("bind=" ));
3723          switch (ELF_ST_BIND(stab[j].st_info)) {
3724             case STB_LOCAL :  IF_DEBUG(linker,debugBelch("local " )); break;
3725             case STB_GLOBAL:  IF_DEBUG(linker,debugBelch("global" )); break;
3726             case STB_WEAK  :  IF_DEBUG(linker,debugBelch("weak  " )); break;
3727             default:          IF_DEBUG(linker,debugBelch("?     " )); break;
3728          }
3729          IF_DEBUG(linker,debugBelch("  " ));
3730
3731          IF_DEBUG(linker,debugBelch("name=%s\n", strtab + stab[j].st_name ));
3732       }
3733    }
3734
3735    if (nsymtabs == 0) {
3736       errorBelch("%s: didn't find any symbol tables", oc->fileName);
3737       return 0;
3738    }
3739
3740    return 1;
3741 }
3742
3743 static int getSectionKind_ELF( Elf_Shdr *hdr, int *is_bss )
3744 {
3745     *is_bss = FALSE;
3746
3747     if (hdr->sh_type == SHT_PROGBITS
3748         && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_EXECINSTR)) {
3749         /* .text-style section */
3750         return SECTIONKIND_CODE_OR_RODATA;
3751     }
3752
3753     if (hdr->sh_type == SHT_PROGBITS
3754             && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
3755             /* .data-style section */
3756             return SECTIONKIND_RWDATA;
3757     }
3758
3759     if (hdr->sh_type == SHT_PROGBITS
3760         && (hdr->sh_flags & SHF_ALLOC) && !(hdr->sh_flags & SHF_WRITE)) {
3761         /* .rodata-style section */
3762         return SECTIONKIND_CODE_OR_RODATA;
3763     }
3764
3765     if (hdr->sh_type == SHT_NOBITS
3766         && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
3767         /* .bss-style section */
3768         *is_bss = TRUE;
3769         return SECTIONKIND_RWDATA;
3770     }
3771
3772     return SECTIONKIND_OTHER;
3773 }
3774
3775
3776 static int
3777 ocGetNames_ELF ( ObjectCode* oc )
3778 {
3779    int i, j, k, nent;
3780    Elf_Sym* stab;
3781
3782    char*     ehdrC    = (char*)(oc->image);
3783    Elf_Ehdr* ehdr     = (Elf_Ehdr*)ehdrC;
3784    char*     strtab   = findElfSection ( ehdrC, SHT_STRTAB );
3785    Elf_Shdr* shdr     = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3786
3787    ASSERT(symhash != NULL);
3788
3789    if (!strtab) {
3790       errorBelch("%s: no strtab", oc->fileName);
3791       return 0;
3792    }
3793
3794    k = 0;
3795    for (i = 0; i < ehdr->e_shnum; i++) {
3796       /* Figure out what kind of section it is.  Logic derived from
3797          Figure 1.14 ("Special Sections") of the ELF document
3798          ("Portable Formats Specification, Version 1.1"). */
3799       int         is_bss = FALSE;
3800       SectionKind kind   = getSectionKind_ELF(&shdr[i], &is_bss);
3801
3802       if (is_bss && shdr[i].sh_size > 0) {
3803          /* This is a non-empty .bss section.  Allocate zeroed space for
3804             it, and set its .sh_offset field such that
3805             ehdrC + .sh_offset == addr_of_zeroed_space.  */
3806          char* zspace = stgCallocBytes(1, shdr[i].sh_size,
3807                                        "ocGetNames_ELF(BSS)");
3808          shdr[i].sh_offset = ((char*)zspace) - ((char*)ehdrC);
3809          /*
3810          debugBelch("BSS section at 0x%x, size %d\n",
3811                          zspace, shdr[i].sh_size);
3812          */
3813       }
3814
3815       /* fill in the section info */
3816       if (kind != SECTIONKIND_OTHER && shdr[i].sh_size > 0) {
3817          addProddableBlock(oc, ehdrC + shdr[i].sh_offset, shdr[i].sh_size);
3818          addSection(oc, kind, ehdrC + shdr[i].sh_offset,
3819                         ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1);
3820       }
3821
3822       if (shdr[i].sh_type != SHT_SYMTAB) continue;
3823
3824       /* copy stuff into this module's object symbol table */
3825       stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
3826       nent = shdr[i].sh_size / sizeof(Elf_Sym);
3827
3828       oc->n_symbols = nent;
3829       oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
3830                                    "ocGetNames_ELF(oc->symbols)");
3831
3832       for (j = 0; j < nent; j++) {
3833
3834          char  isLocal = FALSE; /* avoids uninit-var warning */
3835          char* ad      = NULL;
3836          char* nm      = strtab + stab[j].st_name;
3837          int   secno   = stab[j].st_shndx;
3838
3839          /* Figure out if we want to add it; if so, set ad to its
3840             address.  Otherwise leave ad == NULL. */
3841
3842          if (secno == SHN_COMMON) {
3843             isLocal = FALSE;
3844             ad = stgCallocBytes(1, stab[j].st_size, "ocGetNames_ELF(COMMON)");
3845             /*
3846             debugBelch("COMMON symbol, size %d name %s\n",
3847                             stab[j].st_size, nm);
3848             */
3849             /* Pointless to do addProddableBlock() for this area,
3850                since the linker should never poke around in it. */
3851          }
3852          else
3853          if ( ( ELF_ST_BIND(stab[j].st_info)==STB_GLOBAL
3854                 || ELF_ST_BIND(stab[j].st_info)==STB_LOCAL
3855               )
3856               /* and not an undefined symbol */
3857               && stab[j].st_shndx != SHN_UNDEF
3858               /* and not in a "special section" */
3859               && stab[j].st_shndx < SHN_LORESERVE
3860               &&
3861               /* and it's a not a section or string table or anything silly */
3862               ( ELF_ST_TYPE(stab[j].st_info)==STT_FUNC ||
3863                 ELF_ST_TYPE(stab[j].st_info)==STT_OBJECT ||
3864                 ELF_ST_TYPE(stab[j].st_info)==STT_NOTYPE
3865               )
3866             ) {
3867             /* Section 0 is the undefined section, hence > and not >=. */
3868             ASSERT(secno > 0 && secno < ehdr->e_shnum);
3869             /*
3870             if (shdr[secno].sh_type == SHT_NOBITS) {
3871                debugBelch("   BSS symbol, size %d off %d name %s\n",
3872                                stab[j].st_size, stab[j].st_value, nm);
3873             }
3874             */
3875             ad = ehdrC + shdr[ secno ].sh_offset + stab[j].st_value;
3876             if (ELF_ST_BIND(stab[j].st_info)==STB_LOCAL) {
3877                isLocal = TRUE;
3878             } else {
3879 #ifdef ELF_FUNCTION_DESC
3880                /* dlsym() and the initialisation table both give us function
3881                 * descriptors, so to be consistent we store function descriptors
3882                 * in the symbol table */
3883                if (ELF_ST_TYPE(stab[j].st_info) == STT_FUNC)
3884                    ad = (char *)allocateFunctionDesc((Elf_Addr)ad);
3885 #endif
3886                IF_DEBUG(linker,debugBelch( "addOTabName(GLOB): %10p  %s %s\n",
3887                                       ad, oc->fileName, nm ));
3888                isLocal = FALSE;
3889             }
3890          }
3891
3892          /* And the decision is ... */
3893
3894          if (ad != NULL) {
3895             ASSERT(nm != NULL);
3896             oc->symbols[j] = nm;
3897             /* Acquire! */
3898             if (isLocal) {
3899                /* Ignore entirely. */
3900             } else {
3901                ghciInsertStrHashTable(oc->fileName, symhash, nm, ad);
3902             }
3903          } else {
3904             /* Skip. */
3905             IF_DEBUG(linker,debugBelch( "skipping `%s'\n",
3906                                    strtab + stab[j].st_name ));
3907             /*
3908             debugBelch(
3909                     "skipping   bind = %d,  type = %d,  shndx = %d   `%s'\n",
3910                     (int)ELF_ST_BIND(stab[j].st_info),
3911                     (int)ELF_ST_TYPE(stab[j].st_info),
3912                     (int)stab[j].st_shndx,
3913                     strtab + stab[j].st_name
3914                    );
3915             */
3916             oc->symbols[j] = NULL;
3917          }
3918
3919       }
3920    }
3921
3922    return 1;
3923 }
3924
3925 /* Do ELF relocations which lack an explicit addend.  All x86-linux
3926    relocations appear to be of this form. */
3927 static int
3928 do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
3929                          Elf_Shdr* shdr, int shnum,
3930                          Elf_Sym*  stab, char* strtab )
3931 {
3932    int j;
3933    char *symbol;
3934    Elf_Word* targ;
3935    Elf_Rel*  rtab = (Elf_Rel*) (ehdrC + shdr[shnum].sh_offset);
3936    int         nent = shdr[shnum].sh_size / sizeof(Elf_Rel);
3937    int target_shndx = shdr[shnum].sh_info;
3938    int symtab_shndx = shdr[shnum].sh_link;
3939
3940    stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3941    targ  = (Elf_Word*)(ehdrC + shdr[ target_shndx ].sh_offset);
3942    IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3943                           target_shndx, symtab_shndx ));
3944
3945    /* Skip sections that we're not interested in. */
3946    {
3947        int is_bss;
3948        SectionKind kind = getSectionKind_ELF(&shdr[target_shndx], &is_bss);
3949        if (kind == SECTIONKIND_OTHER) {
3950            IF_DEBUG(linker,debugBelch( "skipping (target section not loaded)"));
3951            return 1;
3952        }
3953    }
3954
3955    for (j = 0; j < nent; j++) {
3956       Elf_Addr offset = rtab[j].r_offset;
3957       Elf_Addr info   = rtab[j].r_info;
3958
3959       Elf_Addr  P  = ((Elf_Addr)targ) + offset;
3960       Elf_Word* pP = (Elf_Word*)P;
3961       Elf_Addr  A  = *pP;
3962       Elf_Addr  S;
3963       void*     S_tmp;
3964       Elf_Addr  value;
3965       StgStablePtr stablePtr;
3966       StgPtr stableVal;
3967
3968       IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p)",
3969                              j, (void*)offset, (void*)info ));
3970       if (!info) {
3971          IF_DEBUG(linker,debugBelch( " ZERO" ));
3972          S = 0;
3973       } else {
3974          Elf_Sym sym = stab[ELF_R_SYM(info)];
3975          /* First see if it is a local symbol. */
3976          if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3977             /* Yes, so we can get the address directly from the ELF symbol
3978                table. */
3979             symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3980             S = (Elf_Addr)
3981                 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3982                        + stab[ELF_R_SYM(info)].st_value);
3983
3984          } else {
3985             symbol = strtab + sym.st_name;
3986             stablePtr = (StgStablePtr)lookupHashTable(stablehash, (StgWord)symbol);
3987             if (NULL == stablePtr) {
3988               /* No, so look up the name in our global table. */
3989               S_tmp = lookupSymbol( symbol );
3990               S = (Elf_Addr)S_tmp;
3991             } else {
3992               stableVal = deRefStablePtr( stablePtr );
3993               S_tmp = stableVal;
3994               S = (Elf_Addr)S_tmp;
3995             }
3996          }
3997          if (!S) {
3998             errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3999             return 0;
4000          }
4001          IF_DEBUG(linker,debugBelch( "`%s' resolves to %p\n", symbol, (void*)S ));
4002       }
4003
4004       IF_DEBUG(linker,debugBelch( "Reloc: P = %p   S = %p   A = %p\n",
4005                              (void*)P, (void*)S, (void*)A ));
4006       checkProddableBlock ( oc, pP );
4007
4008       value = S + A;
4009
4010       switch (ELF_R_TYPE(info)) {
4011 #        ifdef i386_HOST_ARCH
4012          case R_386_32:   *pP = value;     break;
4013          case R_386_PC32: *pP = value - P; break;
4014 #        endif
4015          default:
4016             errorBelch("%s: unhandled ELF relocation(Rel) type %lu\n",
4017                   oc->fileName, (lnat)ELF_R_TYPE(info));
4018             return 0;
4019       }
4020
4021    }
4022    return 1;
4023 }
4024
4025 /* Do ELF relocations for which explicit addends are supplied.
4026    sparc-solaris relocations appear to be of this form. */
4027 static int
4028 do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
4029                           Elf_Shdr* shdr, int shnum,
4030                           Elf_Sym*  stab, char* strtab )
4031 {
4032    int j;
4033    char *symbol = NULL;
4034    Elf_Addr targ;
4035    Elf_Rela* rtab = (Elf_Rela*) (ehdrC + shdr[shnum].sh_offset);
4036    int         nent = shdr[shnum].sh_size / sizeof(Elf_Rela);
4037    int target_shndx = shdr[shnum].sh_info;
4038    int symtab_shndx = shdr[shnum].sh_link;
4039
4040    stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
4041    targ  = (Elf_Addr) (ehdrC + shdr[ target_shndx ].sh_offset);
4042    IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
4043                           target_shndx, symtab_shndx ));
4044
4045    for (j = 0; j < nent; j++) {
4046 #if defined(DEBUG) || defined(sparc_HOST_ARCH) || defined(ia64_HOST_ARCH) || defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
4047       /* This #ifdef only serves to avoid unused-var warnings. */
4048       Elf_Addr  offset = rtab[j].r_offset;
4049       Elf_Addr  P      = targ + offset;
4050 #endif
4051       Elf_Addr  info   = rtab[j].r_info;
4052       Elf_Addr  A      = rtab[j].r_addend;
4053       Elf_Addr  S;
4054       void*     S_tmp;
4055       Elf_Addr  value;
4056 #     if defined(sparc_HOST_ARCH)
4057       Elf_Word* pP = (Elf_Word*)P;
4058       Elf_Word  w1, w2;
4059 #     elif defined(powerpc_HOST_ARCH)
4060       Elf_Sword delta;
4061 #     endif
4062
4063       IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p %6p)   ",
4064                              j, (void*)offset, (void*)info,
4065                                 (void*)A ));
4066       if (!info) {
4067          IF_DEBUG(linker,debugBelch( " ZERO" ));
4068          S = 0;
4069       } else {
4070          Elf_Sym sym = stab[ELF_R_SYM(info)];
4071          /* First see if it is a local symbol. */
4072          if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
4073             /* Yes, so we can get the address directly from the ELF symbol
4074                table. */
4075             symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
4076             S = (Elf_Addr)
4077                 (ehdrC + shdr[ sym.st_shndx ].sh_offset
4078                        + stab[ELF_R_SYM(info)].st_value);
4079 #ifdef ELF_FUNCTION_DESC
4080             /* Make a function descriptor for this function */
4081             if (S && ELF_ST_TYPE(sym.st_info) == STT_FUNC) {
4082                S = allocateFunctionDesc(S + A);
4083                A = 0;
4084             }
4085 #endif
4086          } else {
4087             /* No, so look up the name in our global table. */
4088             symbol = strtab + sym.st_name;
4089             S_tmp = lookupSymbol( symbol );
4090             S = (Elf_Addr)S_tmp;
4091
4092 #ifdef ELF_FUNCTION_DESC
4093             /* If a function, already a function descriptor - we would
4094                have to copy it to add an offset. */
4095             if (S && (ELF_ST_TYPE(sym.st_info) == STT_FUNC) && (A != 0))
4096                errorBelch("%s: function %s with addend %p", oc->fileName, symbol, (void *)A);
4097 #endif
4098          }
4099          if (!S) {
4100            errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
4101            return 0;
4102          }
4103          IF_DEBUG(linker,debugBelch( "`%s' resolves to %p", symbol, (void*)S ));
4104       }
4105
4106       IF_DEBUG(linker,debugBelch("Reloc: P = %p   S = %p   A = %p\n",
4107                                         (void*)P, (void*)S, (void*)A ));
4108       /* checkProddableBlock ( oc, (void*)P ); */
4109
4110       value = S + A;
4111
4112       switch (ELF_R_TYPE(info)) {
4113 #        if defined(sparc_HOST_ARCH)
4114          case R_SPARC_WDISP30:
4115             w1 = *pP & 0xC0000000;
4116             w2 = (Elf_Word)((value - P) >> 2);
4117             ASSERT((w2 & 0xC0000000) == 0);
4118             w1 |= w2;
4119             *pP = w1;
4120             break;
4121          case R_SPARC_HI22:
4122             w1 = *pP & 0xFFC00000;
4123             w2 = (Elf_Word)(value >> 10);
4124             ASSERT((w2 & 0xFFC00000) == 0);
4125             w1 |= w2;
4126             *pP = w1;
4127             break;
4128          case R_SPARC_LO10:
4129             w1 = *pP & ~0x3FF;
4130             w2 = (Elf_Word)(value & 0x3FF);
4131             ASSERT((w2 & ~0x3FF) == 0);
4132             w1 |= w2;
4133             *pP = w1;
4134             break;
4135
4136          /* According to the Sun documentation:
4137             R_SPARC_UA32
4138             This relocation type resembles R_SPARC_32, except it refers to an
4139             unaligned word. That is, the word to be relocated must be treated
4140             as four separate bytes with arbitrary alignment, not as a word
4141             aligned according to the architecture requirements.
4142          */
4143          case R_SPARC_UA32:
4144             w2  = (Elf_Word)value;
4145
4146             // SPARC doesn't do misaligned writes of 32 bit words,
4147             //       so we have to do this one byte-at-a-time.
4148             char *pPc   = (char*)pP;
4149             pPc[0]      = (char) ((Elf_Word)(w2 & 0xff000000) >> 24);
4150             pPc[1]      = (char) ((Elf_Word)(w2 & 0x00ff0000) >> 16);
4151             pPc[2]      = (char) ((Elf_Word)(w2 & 0x0000ff00) >> 8);
4152             pPc[3]      = (char) ((Elf_Word)(w2 & 0x000000ff));
4153             break;
4154
4155          case R_SPARC_32:
4156             w2 = (Elf_Word)value;
4157             *pP = w2;
4158             break;
4159 #        elif defined(powerpc_HOST_ARCH)
4160          case R_PPC_ADDR16_LO:
4161             *(Elf32_Half*) P = value;
4162             break;
4163
4164          case R_PPC_ADDR16_HI:
4165             *(Elf32_Half*) P = value >> 16;
4166             break;
4167
4168          case R_PPC_ADDR16_HA:
4169             *(Elf32_Half*) P = (value + 0x8000) >> 16;
4170             break;
4171
4172          case R_PPC_ADDR32:
4173             *(Elf32_Word *) P = value;
4174             break;
4175
4176          case R_PPC_REL32:
4177             *(Elf32_Word *) P = value - P;
4178             break;
4179
4180          case R_PPC_REL24:
4181             delta = value - P;
4182
4183             if( delta << 6 >> 6 != delta )
4184             {
4185                value = (Elf_Addr) (&makeSymbolExtra( oc, ELF_R_SYM(info), value )
4186                                         ->jumpIsland);
4187                delta = value - P;
4188
4189                if( value == 0 || delta << 6 >> 6 != delta )
4190                {
4191                   barf( "Unable to make SymbolExtra for #%d",
4192                         ELF_R_SYM(info) );
4193                   return 0;
4194                }
4195             }
4196
4197             *(Elf_Word *) P = (*(Elf_Word *) P & 0xfc000003)
4198                                           | (delta & 0x3fffffc);
4199             break;
4200 #        endif
4201
4202 #if x86_64_HOST_ARCH
4203       case R_X86_64_64:
4204           *(Elf64_Xword *)P = value;
4205           break;
4206
4207       case R_X86_64_PC32:
4208       {
4209 #if defined(ALWAYS_PIC)
4210           barf("R_X86_64_PC32 relocation, but ALWAYS_PIC.");
4211 #else
4212           StgInt64 off = value - P;
4213           if (off >= 0x7fffffffL || off < -0x80000000L) {
4214 #if X86_64_ELF_NONPIC_HACK
4215               StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
4216                                                 -> jumpIsland;
4217               off = pltAddress + A - P;
4218 #else
4219               barf("R_X86_64_PC32 relocation out of range: %s = %p\nRecompile %s with -fPIC.",
4220                    symbol, off, oc->fileName );
4221 #endif
4222           }
4223           *(Elf64_Word *)P = (Elf64_Word)off;
4224 #endif
4225           break;
4226       }
4227
4228       case R_X86_64_PC64:
4229       {
4230           StgInt64 off = value - P;
4231           *(Elf64_Word *)P = (Elf64_Word)off;
4232           break;
4233       }
4234
4235       case R_X86_64_32:
4236 #if defined(ALWAYS_PIC)
4237           barf("R_X86_64_32 relocation, but ALWAYS_PIC.");
4238 #else
4239           if (value >= 0x7fffffffL) {
4240 #if X86_64_ELF_NONPIC_HACK
4241               StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
4242                                                 -> jumpIsland;
4243               value = pltAddress + A;
4244 #else
4245               barf("R_X86_64_32 relocation out of range: %s = %p\nRecompile %s with -fPIC.",
4246                    symbol, value, oc->fileName );
4247 #endif
4248           }
4249           *(Elf64_Word *)P = (Elf64_Word)value;
4250 #endif
4251           break;
4252
4253       case R_X86_64_32S:
4254 #if defined(ALWAYS_PIC)
4255           barf("R_X86_64_32S relocation, but ALWAYS_PIC.");
4256 #else
4257           if ((StgInt64)value > 0x7fffffffL || (StgInt64)value < -0x80000000L) {
4258 #if X86_64_ELF_NONPIC_HACK
4259               StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
4260                                                 -> jumpIsland;
4261               value = pltAddress + A;
4262 #else
4263               barf("R_X86_64_32S relocation out of range: %s = %p\nRecompile %s with -fPIC.",
4264                    symbol, value, oc->fileName );
4265 #endif
4266           }
4267           *(Elf64_Sword *)P = (Elf64_Sword)value;
4268 #endif
4269           break;
4270
4271       case R_X86_64_GOTPCREL:
4272       {
4273           StgInt64 gotAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)->addr;
4274           StgInt64 off = gotAddress + A - P;
4275           *(Elf64_Word *)P = (Elf64_Word)off;
4276           break;
4277       }
4278
4279       case R_X86_64_PLT32:
4280       {
4281 #if defined(ALWAYS_PIC)
4282           barf("R_X86_64_PLT32 relocation, but ALWAYS_PIC.");
4283 #else
4284           StgInt64 off = value - P;
4285           if (off >= 0x7fffffffL || off < -0x80000000L) {
4286               StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
4287                                                     -> jumpIsland;
4288               off = pltAddress + A - P;
4289           }
4290           *(Elf64_Word *)P = (Elf64_Word)off;
4291 #endif
4292           break;
4293       }
4294 #endif
4295
4296          default:
4297             errorBelch("%s: unhandled ELF relocation(RelA) type %lu\n",
4298                   oc->fileName, (lnat)ELF_R_TYPE(info));
4299             return 0;
4300       }
4301
4302    }
4303    return 1;
4304 }
4305
4306 static int
4307 ocResolve_ELF ( ObjectCode* oc )
4308 {
4309    char *strtab;
4310    int   shnum, ok;
4311    Elf_Sym*  stab  = NULL;
4312    char*     ehdrC = (char*)(oc->image);
4313    Elf_Ehdr* ehdr  = (Elf_Ehdr*) ehdrC;
4314    Elf_Shdr* shdr  = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
4315
4316    /* first find "the" symbol table */
4317    stab = (Elf_Sym*) findElfSection ( ehdrC, SHT_SYMTAB );
4318
4319    /* also go find the string table */
4320    strtab = findElfSection ( ehdrC, SHT_STRTAB );
4321
4322    if (stab == NULL || strtab == NULL) {
4323       errorBelch("%s: can't find string or symbol table", oc->fileName);
4324       return 0;
4325    }
4326
4327    /* Process the relocation sections. */
4328    for (shnum = 0; shnum < ehdr->e_shnum; shnum++) {
4329       if (shdr[shnum].sh_type == SHT_REL) {
4330          ok = do_Elf_Rel_relocations ( oc, ehdrC, shdr,
4331                                        shnum, stab, strtab );
4332          if (!ok) return ok;
4333       }
4334       else
4335       if (shdr[shnum].sh_type == SHT_RELA) {
4336          ok = do_Elf_Rela_relocations ( oc, ehdrC, shdr,
4337                                         shnum, stab, strtab );
4338          if (!ok) return ok;
4339       }
4340    }
4341
4342 #if defined(powerpc_HOST_ARCH)
4343    ocFlushInstructionCache( oc );
4344 #endif
4345
4346    return 1;
4347 }
4348
4349 /*
4350  * PowerPC & X86_64 ELF specifics
4351  */
4352
4353 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
4354
4355 static int ocAllocateSymbolExtras_ELF( ObjectCode *oc )
4356 {
4357   Elf_Ehdr *ehdr;
4358   Elf_Shdr* shdr;
4359   int i;
4360
4361   ehdr = (Elf_Ehdr *) oc->image;
4362   shdr = (Elf_Shdr *) ( ((char *)oc->image) + ehdr->e_shoff );
4363
4364   for( i = 0; i < ehdr->e_shnum; i++ )
4365     if( shdr[i].sh_type == SHT_SYMTAB )
4366       break;
4367
4368   if( i == ehdr->e_shnum )
4369   {
4370     errorBelch( "This ELF file contains no symtab" );
4371     return 0;
4372   }
4373
4374   if( shdr[i].sh_entsize != sizeof( Elf_Sym ) )
4375   {
4376     errorBelch( "The entry size (%d) of the symtab isn't %d\n",
4377       (int) shdr[i].sh_entsize, (int) sizeof( Elf_Sym ) );
4378
4379     return 0;
4380   }
4381
4382   return ocAllocateSymbolExtras( oc, shdr[i].sh_size / sizeof( Elf_Sym ), 0 );
4383 }
4384
4385 #endif /* powerpc */
4386
4387 #endif /* ELF */
4388
4389 /* --------------------------------------------------------------------------
4390  * Mach-O specifics
4391  * ------------------------------------------------------------------------*/
4392
4393 #if defined(OBJFORMAT_MACHO)
4394
4395 /*
4396   Support for MachO linking on Darwin/MacOS X
4397   by Wolfgang Thaller (wolfgang.thaller@gmx.net)
4398
4399   I hereby formally apologize for the hackish nature of this code.
4400   Things that need to be done:
4401   *) implement ocVerifyImage_MachO
4402   *) add still more sanity checks.
4403 */
4404
4405 #if x86_64_HOST_ARCH || powerpc64_HOST_ARCH
4406 #define mach_header mach_header_64
4407 #define segment_command segment_command_64
4408 #define section section_64
4409 #define nlist nlist_64
4410 #endif
4411
4412 #ifdef powerpc_HOST_ARCH
4413 static int ocAllocateSymbolExtras_MachO(ObjectCode* oc)
4414 {
4415     struct mach_header *header = (struct mach_header *) oc->image;
4416     struct load_command *lc = (struct load_command *) (header + 1);
4417     unsigned i;
4418
4419     for( i = 0; i < header->ncmds; i++ )
4420     {
4421         if( lc->cmd == LC_SYMTAB )
4422         {
4423                 // Find out the first and last undefined external
4424                 // symbol, so we don't have to allocate too many
4425                 // jump islands.
4426             struct symtab_command *symLC = (struct symtab_command *) lc;
4427             unsigned min = symLC->nsyms, max = 0;
4428             struct nlist *nlist =
4429                 symLC ? (struct nlist*) ((char*) oc->image + symLC->symoff)
4430                       : NULL;
4431             for(i=0;i<symLC->nsyms;i++)
4432             {
4433                 if(nlist[i].n_type & N_STAB)
4434                     ;
4435                 else if(nlist[i].n_type & N_EXT)
4436                 {
4437                     if((nlist[i].n_type & N_TYPE) == N_UNDF
4438                         && (nlist[i].n_value == 0))
4439                     {
4440                         if(i < min)
4441                             min = i;
4442                         if(i > max)
4443                             max = i;
4444                     }
4445                 }
4446             }
4447             if(max >= min)
4448                 return ocAllocateSymbolExtras(oc, max - min + 1, min);
4449
4450             break;
4451         }
4452
4453         lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
4454     }
4455     return ocAllocateSymbolExtras(oc,0,0);
4456 }
4457 #endif
4458 #ifdef x86_64_HOST_ARCH
4459 static int ocAllocateSymbolExtras_MachO(ObjectCode* oc)
4460 {
4461     struct mach_header *header = (struct mach_header *) oc->image;
4462     struct load_command *lc = (struct load_command *) (header + 1);
4463     unsigned i;
4464
4465     for( i = 0; i < header->ncmds; i++ )
4466     {
4467         if( lc->cmd == LC_SYMTAB )
4468         {
4469                 // Just allocate one entry for every symbol
4470             struct symtab_command *symLC = (struct symtab_command *) lc;
4471
4472             return ocAllocateSymbolExtras(oc, symLC->nsyms, 0);
4473         }
4474
4475         lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
4476     }
4477     return ocAllocateSymbolExtras(oc,0,0);
4478 }
4479 #endif
4480
4481 static int ocVerifyImage_MachO(ObjectCode* oc)
4482 {
4483     char *image = (char*) oc->image;
4484     struct mach_header *header = (struct mach_header*) image;
4485
4486 #if x86_64_HOST_ARCH || powerpc64_HOST_ARCH
4487     if(header->magic != MH_MAGIC_64) {
4488         errorBelch("%s: Bad magic. Expected: %08x, got: %08x.\n",
4489                    oc->fileName, MH_MAGIC_64, header->magic);
4490         return 0;
4491     }
4492 #else
4493     if(header->magic != MH_MAGIC) {
4494         errorBelch("%s: Bad magic. Expected: %08x, got: %08x.\n",
4495                    oc->fileName, MH_MAGIC, header->magic);
4496         return 0;
4497     }
4498 #endif
4499     // FIXME: do some more verifying here
4500     return 1;
4501 }
4502
4503 static int resolveImports(
4504     ObjectCode* oc,
4505     char *image,
4506     struct symtab_command *symLC,
4507     struct section *sect,    // ptr to lazy or non-lazy symbol pointer section
4508     unsigned long *indirectSyms,
4509     struct nlist *nlist)
4510 {
4511     unsigned i;
4512     size_t itemSize = 4;
4513
4514     IF_DEBUG(linker, debugBelch("resolveImports: start\n"));
4515
4516 #if i386_HOST_ARCH
4517     int isJumpTable = 0;
4518     if(!strcmp(sect->sectname,"__jump_table"))
4519     {
4520         isJumpTable = 1;
4521         itemSize = 5;
4522         ASSERT(sect->reserved2 == itemSize);
4523     }
4524 #endif
4525
4526     for(i=0; i*itemSize < sect->size;i++)
4527     {
4528         // according to otool, reserved1 contains the first index into the indirect symbol table
4529         struct nlist *symbol = &nlist[indirectSyms[sect->reserved1+i]];
4530         char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4531         void *addr = NULL;
4532
4533         IF_DEBUG(linker, debugBelch("resolveImports: resolving %s\n", nm));
4534         if ((symbol->n_type & N_TYPE) == N_UNDF
4535             && (symbol->n_type & N_EXT) && (symbol->n_value != 0)) {
4536             addr = (void*) (symbol->n_value);
4537             IF_DEBUG(linker, debugBelch("resolveImports: undefined external %s has value %p\n", nm, addr));
4538         } else {
4539             addr = lookupSymbol(nm);
4540             IF_DEBUG(linker, debugBelch("resolveImports: looking up %s, %p\n", nm, addr));
4541         }
4542         if (!addr)
4543         {
4544             errorBelch("\n%s: unknown symbol `%s'", oc->fileName, nm);
4545             return 0;
4546         }
4547         ASSERT(addr);
4548
4549 #if i386_HOST_ARCH
4550         if(isJumpTable)
4551         {
4552             checkProddableBlock(oc,image + sect->offset + i*itemSize);
4553             *(image + sect->offset + i*itemSize) = 0xe9; // jmp
4554             *(unsigned*)(image + sect->offset + i*itemSize + 1)
4555                 = (char*)addr - (image + sect->offset + i*itemSize + 5);
4556         }
4557         else
4558 #endif
4559         {
4560             checkProddableBlock(oc,((void**)(image + sect->offset)) + i);
4561             ((void**)(image + sect->offset))[i] = addr;
4562         }
4563     }
4564
4565     IF_DEBUG(linker, debugBelch("resolveImports: done\n"));
4566     return 1;
4567 }
4568
4569 static unsigned long relocateAddress(
4570     ObjectCode* oc,
4571     int nSections,
4572     struct section* sections,
4573     unsigned long address)
4574 {
4575     int i;
4576     IF_DEBUG(linker, debugBelch("relocateAddress: start\n"));
4577     for (i = 0; i < nSections; i++)
4578     {
4579             IF_DEBUG(linker, debugBelch("    relocating address in section %d\n", i));
4580         if (sections[i].addr <= address
4581             && address < sections[i].addr + sections[i].size)
4582         {
4583             return (unsigned long)oc->image
4584                     + sections[i].offset + address - sections[i].addr;
4585         }
4586     }
4587     barf("Invalid Mach-O file:"
4588          "Address out of bounds while relocating object file");
4589     return 0;
4590 }
4591
4592 static int relocateSection(
4593     ObjectCode* oc,
4594     char *image,
4595     struct symtab_command *symLC, struct nlist *nlist,
4596     int nSections, struct section* sections, struct section *sect)
4597 {
4598     struct relocation_info *relocs;
4599     int i, n;
4600
4601     IF_DEBUG(linker, debugBelch("relocateSection: start\n"));
4602
4603     if(!strcmp(sect->sectname,"__la_symbol_ptr"))
4604         return 1;
4605     else if(!strcmp(sect->sectname,"__nl_symbol_ptr"))
4606         return 1;
4607     else if(!strcmp(sect->sectname,"__la_sym_ptr2"))
4608         return 1;
4609     else if(!strcmp(sect->sectname,"__la_sym_ptr3"))
4610         return 1;
4611
4612     n = sect->nreloc;
4613     IF_DEBUG(linker, debugBelch("relocateSection: number of relocations: %d\n", n));
4614
4615     relocs = (struct relocation_info*) (image + sect->reloff);
4616
4617     for(i=0;i<n;i++)
4618     {
4619 #ifdef x86_64_HOST_ARCH
4620         struct relocation_info *reloc = &relocs[i];
4621
4622         char    *thingPtr = image + sect->offset + reloc->r_address;
4623         uint64_t thing;
4624         /* We shouldn't need to initialise this, but gcc on OS X 64 bit
4625            complains that it may be used uninitialized if we don't */
4626         uint64_t value = 0;
4627         uint64_t baseValue;
4628         int type = reloc->r_type;
4629
4630         checkProddableBlock(oc,thingPtr);
4631         switch(reloc->r_length)
4632         {
4633             case 0:
4634                 thing = *(uint8_t*)thingPtr;
4635                 baseValue = (uint64_t)thingPtr + 1;
4636                 break;
4637             case 1:
4638                 thing = *(uint16_t*)thingPtr;
4639                 baseValue = (uint64_t)thingPtr + 2;
4640                 break;
4641             case 2:
4642                 thing = *(uint32_t*)thingPtr;
4643                 baseValue = (uint64_t)thingPtr + 4;
4644                 break;
4645             case 3:
4646                 thing = *(uint64_t*)thingPtr;
4647                 baseValue = (uint64_t)thingPtr + 8;
4648                 break;
4649             default:
4650                 barf("Unknown size.");
4651         }
4652
4653         IF_DEBUG(linker,
4654                  debugBelch("relocateSection: length = %d, thing = %d, baseValue = %p\n",
4655                             reloc->r_length, thing, baseValue));
4656
4657         if (type == X86_64_RELOC_GOT
4658            || type == X86_64_RELOC_GOT_LOAD)
4659         {
4660             struct nlist *symbol = &nlist[reloc->r_symbolnum];
4661             char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4662
4663             IF_DEBUG(linker, debugBelch("relocateSection: making jump island for %s, extern = %d, X86_64_RELOC_GOT\n", nm, reloc->r_extern));
4664             ASSERT(reloc->r_extern);
4665             value = (uint64_t) &makeSymbolExtra(oc, reloc->r_symbolnum, (unsigned long)lookupSymbol(nm))->addr;
4666
4667             type = X86_64_RELOC_SIGNED;
4668         }
4669         else if(reloc->r_extern)
4670         {
4671             struct nlist *symbol = &nlist[reloc->r_symbolnum];
4672             char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4673
4674             IF_DEBUG(linker, debugBelch("relocateSection: looking up external symbol %s\n", nm));
4675             IF_DEBUG(linker, debugBelch("               : type  = %d\n", symbol->n_type));
4676             IF_DEBUG(linker, debugBelch("               : sect  = %d\n", symbol->n_sect));
4677             IF_DEBUG(linker, debugBelch("               : desc  = %d\n", symbol->n_desc));
4678             IF_DEBUG(linker, debugBelch("               : value = %p\n", (void *)symbol->n_value));
4679             if ((symbol->n_type & N_TYPE) == N_SECT) {
4680                 value = relocateAddress(oc, nSections, sections,
4681                                         symbol->n_value);
4682                 IF_DEBUG(linker, debugBelch("relocateSection, defined external symbol %s, relocated address %p\n", nm, (void *)value));
4683             }
4684             else {
4685                 value = (uint64_t) lookupSymbol(nm);
4686                 IF_DEBUG(linker, debugBelch("relocateSection: external symbol %s, address %p\n", nm, (void *)value));
4687             }
4688         }
4689         else
4690         {
4691             value = sections[reloc->r_symbolnum-1].offset
4692                   - sections[reloc->r_symbolnum-1].addr
4693                   + (uint64_t) image;
4694         }
4695
4696         IF_DEBUG(linker, debugBelch("relocateSection: value = %p\n", (void *)value));
4697
4698         if (type == X86_64_RELOC_BRANCH)
4699         {
4700             if((int32_t)(value - baseValue) != (int64_t)(value - baseValue))
4701             {
4702                 ASSERT(reloc->r_extern);
4703                 value = (uint64_t) &makeSymbolExtra(oc, reloc->r_symbolnum, value)
4704                                         -> jumpIsland;
4705             }
4706             ASSERT((int32_t)(value - baseValue) == (int64_t)(value - baseValue));
4707             type = X86_64_RELOC_SIGNED;
4708         }
4709
4710         switch(type)
4711         {
4712             case X86_64_RELOC_UNSIGNED:
4713                 ASSERT(!reloc->r_pcrel);
4714                 thing += value;
4715                 break;
4716             case X86_64_RELOC_SIGNED:
4717             case X86_64_RELOC_SIGNED_1:
4718             case X86_64_RELOC_SIGNED_2:
4719             case X86_64_RELOC_SIGNED_4:
4720                 ASSERT(reloc->r_pcrel);
4721                 thing += value - baseValue;
4722                 break;
4723             case X86_64_RELOC_SUBTRACTOR:
4724                 ASSERT(!reloc->r_pcrel);
4725                 thing -= value;
4726                 break;
4727             default:
4728                 barf("unkown relocation");
4729         }
4730
4731         switch(reloc->r_length)
4732         {
4733             case 0:
4734                 *(uint8_t*)thingPtr = thing;
4735                 break;
4736             case 1:
4737                 *(uint16_t*)thingPtr = thing;
4738                 break;
4739             case 2:
4740                 *(uint32_t*)thingPtr = thing;
4741                 break;
4742             case 3:
4743                 *(uint64_t*)thingPtr = thing;
4744                 break;
4745         }
4746 #else
4747         if(relocs[i].r_address & R_SCATTERED)
4748         {
4749             struct scattered_relocation_info *scat =
4750                 (struct scattered_relocation_info*) &relocs[i];
4751
4752             if(!scat->r_pcrel)
4753             {
4754                 if(scat->r_length == 2)
4755                 {
4756                     unsigned long word = 0;
4757                     unsigned long* wordPtr = (unsigned long*) (image + sect->offset + scat->r_address);
4758                     checkProddableBlock(oc,wordPtr);
4759
4760                     // Note on relocation types:
4761                     // i386 uses the GENERIC_RELOC_* types,
4762                     // while ppc uses special PPC_RELOC_* types.
4763                     // *_RELOC_VANILLA and *_RELOC_PAIR have the same value
4764                     // in both cases, all others are different.
4765                     // Therefore, we use GENERIC_RELOC_VANILLA
4766                     // and GENERIC_RELOC_PAIR instead of the PPC variants,
4767                     // and use #ifdefs for the other types.
4768
4769                     // Step 1: Figure out what the relocated value should be
4770                     if(scat->r_type == GENERIC_RELOC_VANILLA)
4771                     {
4772                         word = *wordPtr + (unsigned long) relocateAddress(
4773                                                                 oc,
4774                                                                 nSections,
4775                                                                 sections,
4776                                                                 scat->r_value)
4777                                         - scat->r_value;
4778                     }
4779 #ifdef powerpc_HOST_ARCH
4780                     else if(scat->r_type == PPC_RELOC_SECTDIFF
4781                         || scat->r_type == PPC_RELOC_LO16_SECTDIFF
4782                         || scat->r_type == PPC_RELOC_HI16_SECTDIFF
4783                         || scat->r_type == PPC_RELOC_HA16_SECTDIFF
4784                         || scat->r_type == PPC_RELOC_LOCAL_SECTDIFF)
4785 #else
4786                     else if(scat->r_type == GENERIC_RELOC_SECTDIFF
4787                         || scat->r_type == GENERIC_RELOC_LOCAL_SECTDIFF)
4788 #endif
4789                     {
4790                         struct scattered_relocation_info *pair =
4791                                 (struct scattered_relocation_info*) &relocs[i+1];
4792
4793                         if(!pair->r_scattered || pair->r_type != GENERIC_RELOC_PAIR)
4794                             barf("Invalid Mach-O file: "
4795                                  "RELOC_*_SECTDIFF not followed by RELOC_PAIR");
4796
4797                         word = (unsigned long)
4798                                (relocateAddress(oc, nSections, sections, scat->r_value)
4799                               - relocateAddress(oc, nSections, sections, pair->r_value));
4800                         i++;
4801                     }
4802 #ifdef powerpc_HOST_ARCH
4803                     else if(scat->r_type == PPC_RELOC_HI16
4804                          || scat->r_type == PPC_RELOC_LO16
4805                          || scat->r_type == PPC_RELOC_HA16
4806                          || scat->r_type == PPC_RELOC_LO14)
4807                     {   // these are generated by label+offset things
4808                         struct relocation_info *pair = &relocs[i+1];
4809                         if((pair->r_address & R_SCATTERED) || pair->r_type != PPC_RELOC_PAIR)
4810                             barf("Invalid Mach-O file: "
4811                                  "PPC_RELOC_* not followed by PPC_RELOC_PAIR");
4812
4813                         if(scat->r_type == PPC_RELOC_LO16)
4814                         {
4815                             word = ((unsigned short*) wordPtr)[1];
4816                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4817                         }
4818                         else if(scat->r_type == PPC_RELOC_LO14)
4819                         {
4820                             barf("Unsupported Relocation: PPC_RELOC_LO14");
4821                             word = ((unsigned short*) wordPtr)[1] & 0xFFFC;
4822                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4823                         }
4824                         else if(scat->r_type == PPC_RELOC_HI16)
4825                         {
4826                             word = ((unsigned short*) wordPtr)[1] << 16;
4827                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
4828                         }
4829                         else if(scat->r_type == PPC_RELOC_HA16)
4830                         {
4831                             word = ((unsigned short*) wordPtr)[1] << 16;
4832                             word += ((short)relocs[i+1].r_address & (short)0xFFFF);
4833                         }
4834
4835
4836                         word += (unsigned long) relocateAddress(oc, nSections, sections, scat->r_value)
4837                                                 - scat->r_value;
4838
4839                         i++;
4840                     }
4841  #endif
4842                     else
4843                     {
4844                         barf ("Don't know how to handle this Mach-O "
4845                               "scattered relocation entry: "
4846                               "object file %s; entry type %ld; "
4847                               "address %#lx\n",
4848                               OC_INFORMATIVE_FILENAME(oc),
4849                               scat->r_type,
4850                               scat->r_address);
4851                         return 0;
4852                      }
4853
4854 #ifdef powerpc_HOST_ARCH
4855                     if(scat->r_type == GENERIC_RELOC_VANILLA
4856                         || scat->r_type == PPC_RELOC_SECTDIFF)
4857 #else
4858                     if(scat->r_type == GENERIC_RELOC_VANILLA
4859                         || scat->r_type == GENERIC_RELOC_SECTDIFF
4860                         || scat->r_type == GENERIC_RELOC_LOCAL_SECTDIFF)
4861 #endif
4862                     {
4863                         *wordPtr = word;
4864                     }
4865 #ifdef powerpc_HOST_ARCH
4866                     else if(scat->r_type == PPC_RELOC_LO16_SECTDIFF || scat->r_type == PPC_RELOC_LO16)
4867                     {
4868                         ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
4869                     }
4870                     else if(scat->r_type == PPC_RELOC_HI16_SECTDIFF || scat->r_type == PPC_RELOC_HI16)
4871                     {
4872                         ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
4873                     }
4874                     else if(scat->r_type == PPC_RELOC_HA16_SECTDIFF || scat->r_type == PPC_RELOC_HA16)
4875                     {
4876                         ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
4877                             + ((word & (1<<15)) ? 1 : 0);
4878                     }
4879 #endif
4880                 }
4881                 else
4882                 {
4883                     barf("Can't handle Mach-O scattered relocation entry "
4884                          "with this r_length tag: "
4885                          "object file %s; entry type %ld; "
4886                          "r_length tag %ld; address %#lx\n",
4887                          OC_INFORMATIVE_FILENAME(oc),
4888                          scat->r_type,
4889                          scat->r_length,
4890                          scat->r_address);
4891                     return 0;
4892                 }
4893             }
4894             else /* scat->r_pcrel */
4895             {
4896                 barf("Don't know how to handle *PC-relative* Mach-O "
4897                      "scattered relocation entry: "
4898                      "object file %s; entry type %ld; address %#lx\n",
4899                      OC_INFORMATIVE_FILENAME(oc),
4900                      scat->r_type,
4901                      scat->r_address);
4902                return 0;
4903             }
4904
4905         }
4906         else /* !(relocs[i].r_address & R_SCATTERED) */
4907         {
4908             struct relocation_info *reloc = &relocs[i];
4909             if(reloc->r_pcrel && !reloc->r_extern)
4910                 continue;
4911
4912             if(reloc->r_length == 2)
4913             {
4914                 unsigned long word = 0;
4915 #ifdef powerpc_HOST_ARCH
4916                 unsigned long jumpIsland = 0;
4917                 long offsetToJumpIsland = 0xBADBAD42; // initialise to bad value
4918                                                       // to avoid warning and to catch
4919                                                       // bugs.
4920 #endif
4921
4922                 unsigned long* wordPtr = (unsigned long*) (image + sect->offset + reloc->r_address);
4923                 checkProddableBlock(oc,wordPtr);
4924
4925                 if(reloc->r_type == GENERIC_RELOC_VANILLA)
4926                 {
4927                     word = *wordPtr;
4928                 }
4929 #ifdef powerpc_HOST_ARCH
4930                 else if(reloc->r_type == PPC_RELOC_LO16)
4931                 {
4932                     word = ((unsigned short*) wordPtr)[1];
4933                     word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4934                 }
4935                 else if(reloc->r_type == PPC_RELOC_HI16)
4936                 {
4937                     word = ((unsigned short*) wordPtr)[1] << 16;
4938                     word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
4939                 }
4940                 else if(reloc->r_type == PPC_RELOC_HA16)
4941                 {
4942                     word = ((unsigned short*) wordPtr)[1] << 16;
4943                     word += ((short)relocs[i+1].r_address & (short)0xFFFF);
4944                 }
4945                 else if(reloc->r_type == PPC_RELOC_BR24)
4946                 {
4947                     word = *wordPtr;
4948                     word = (word & 0x03FFFFFC) | ((word & 0x02000000) ? 0xFC000000 : 0);
4949                 }
4950 #endif
4951                 else
4952                 {
4953                     barf("Can't handle this Mach-O relocation entry "
4954                          "(not scattered): "
4955                          "object file %s; entry type %ld; address %#lx\n",
4956                          OC_INFORMATIVE_FILENAME(oc),
4957                          reloc->r_type,
4958                          reloc->r_address);
4959                     return 0;
4960                 }
4961
4962                 if(!reloc->r_extern)
4963                 {
4964                     long delta =
4965                         sections[reloc->r_symbolnum-1].offset
4966                         - sections[reloc->r_symbolnum-1].addr
4967                         + ((long) image);
4968
4969                     word += delta;
4970                 }
4971                 else
4972                 {
4973                     struct nlist *symbol = &nlist[reloc->r_symbolnum];
4974                     char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4975                     void *symbolAddress = lookupSymbol(nm);
4976                     if(!symbolAddress)
4977                     {
4978                         errorBelch("\nunknown symbol `%s'", nm);
4979                         return 0;
4980                     }
4981
4982                     if(reloc->r_pcrel)
4983                     {
4984 #ifdef powerpc_HOST_ARCH
4985                             // In the .o file, this should be a relative jump to NULL
4986                             // and we'll change it to a relative jump to the symbol
4987                         ASSERT(word + reloc->r_address == 0);
4988                         jumpIsland = (unsigned long)
4989                                         &makeSymbolExtra(oc,
4990                                                          reloc->r_symbolnum,
4991                                                          (unsigned long) symbolAddress)
4992                                          -> jumpIsland;
4993                         if(jumpIsland != 0)
4994                         {
4995                             offsetToJumpIsland = word + jumpIsland
4996                                 - (((long)image) + sect->offset - sect->addr);
4997                         }
4998 #endif
4999                         word += (unsigned long) symbolAddress
5000                                 - (((long)image) + sect->offset - sect->addr);
5001                     }
5002                     else
5003                     {
5004                         word += (unsigned long) symbolAddress;
5005                     }
5006                 }
5007
5008                 if(reloc->r_type == GENERIC_RELOC_VANILLA)
5009                 {
5010                     *wordPtr = word;
5011                     continue;
5012                 }
5013 #ifdef powerpc_HOST_ARCH
5014                 else if(reloc->r_type == PPC_RELOC_LO16)
5015                 {
5016                     ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
5017                     i++; continue;
5018                 }
5019                 else if(reloc->r_type == PPC_RELOC_HI16)
5020                 {
5021                     ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
5022                     i++; continue;
5023                 }
5024                 else if(reloc->r_type == PPC_RELOC_HA16)
5025                 {
5026                     ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
5027                         + ((word & (1<<15)) ? 1 : 0);
5028                     i++; continue;
5029                 }
5030                 else if(reloc->r_type == PPC_RELOC_BR24)
5031                 {
5032                     if((word & 0x03) != 0)
5033                         barf("%s: unconditional relative branch with a displacement "
5034                              "which isn't a multiple of 4 bytes: %#lx",
5035                              OC_INFORMATIVE_FILENAME(oc),
5036                              word);
5037
5038                     if((word & 0xFE000000) != 0xFE000000 &&
5039                        (word & 0xFE000000) != 0x00000000)
5040                     {
5041                         // The branch offset is too large.
5042                         // Therefore, we try to use a jump island.
5043                         if(jumpIsland == 0)
5044                         {
5045                             barf("%s: unconditional relative branch out of range: "
5046                                  "no jump island available: %#lx",
5047                                  OC_INFORMATIVE_FILENAME(oc),
5048                                  word);
5049                         }
5050
5051                         word = offsetToJumpIsland;
5052                         if((word & 0xFE000000) != 0xFE000000 &&
5053                            (word & 0xFE000000) != 0x00000000)
5054                             barf("%s: unconditional relative branch out of range: "
5055                                  "jump island out of range: %#lx",
5056                                  OC_INFORMATIVE_FILENAME(oc),
5057                                  word);
5058                     }
5059                     *wordPtr = (*wordPtr & 0xFC000003) | (word & 0x03FFFFFC);
5060                     continue;
5061                 }
5062 #endif
5063             }
5064             else
5065             {
5066                  barf("Can't handle Mach-O relocation entry (not scattered) "
5067                       "with this r_length tag: "
5068                       "object file %s; entry type %ld; "
5069                       "r_length tag %ld; address %#lx\n",
5070                       OC_INFORMATIVE_FILENAME(oc),
5071                       reloc->r_type,
5072                       reloc->r_length,
5073                       reloc->r_address);
5074                  return 0;
5075             }
5076         }
5077 #endif
5078     }
5079     IF_DEBUG(linker, debugBelch("relocateSection: done\n"));
5080     return 1;
5081 }
5082
5083 static int ocGetNames_MachO(ObjectCode* oc)
5084 {
5085     char *image = (char*) oc->image;
5086     struct mach_header *header = (struct mach_header*) image;
5087     struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
5088     unsigned i,curSymbol = 0;
5089     struct segment_command *segLC = NULL;
5090     struct section *sections;
5091     struct symtab_command *symLC = NULL;
5092     struct nlist *nlist;
5093     unsigned long commonSize = 0;
5094     char    *commonStorage = NULL;
5095     unsigned long commonCounter;
5096
5097     IF_DEBUG(linker,debugBelch("ocGetNames_MachO: start\n"));
5098
5099     for(i=0;i<header->ncmds;i++)
5100     {
5101         if(lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64)
5102             segLC = (struct segment_command*) lc;
5103         else if(lc->cmd == LC_SYMTAB)
5104             symLC = (struct symtab_command*) lc;
5105         lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
5106     }
5107
5108     sections = (struct section*) (segLC+1);
5109     nlist = symLC ? (struct nlist*) (image + symLC->symoff)
5110                   : NULL;
5111
5112     if(!segLC)
5113         barf("ocGetNames_MachO: no segment load command");
5114
5115     for(i=0;i<segLC->nsects;i++)
5116     {
5117         IF_DEBUG(linker, debugBelch("ocGetNames_MachO: segment %d\n", i));
5118         if (sections[i].size == 0)
5119             continue;
5120
5121         if((sections[i].flags & SECTION_TYPE) == S_ZEROFILL)
5122         {
5123             char * zeroFillArea = stgCallocBytes(1,sections[i].size,
5124                                       "ocGetNames_MachO(common symbols)");
5125             sections[i].offset = zeroFillArea - image;
5126         }
5127
5128         if(!strcmp(sections[i].sectname,"__text"))
5129             addSection(oc, SECTIONKIND_CODE_OR_RODATA,
5130                 (void*) (image + sections[i].offset),
5131                 (void*) (image + sections[i].offset + sections[i].size));
5132         else if(!strcmp(sections[i].sectname,"__const"))
5133             addSection(oc, SECTIONKIND_RWDATA,
5134                 (void*) (image + sections[i].offset),
5135                 (void*) (image + sections[i].offset + sections[i].size));
5136         else if(!strcmp(sections[i].sectname,"__data"))
5137             addSection(oc, SECTIONKIND_RWDATA,
5138                 (void*) (image + sections[i].offset),
5139                 (void*) (image + sections[i].offset + sections[i].size));
5140         else if(!strcmp(sections[i].sectname,"__bss")
5141                 || !strcmp(sections[i].sectname,"__common"))
5142             addSection(oc, SECTIONKIND_RWDATA,
5143                 (void*) (image + sections[i].offset),
5144                 (void*) (image + sections[i].offset + sections[i].size));
5145
5146         addProddableBlock(oc, (void*) (image + sections[i].offset),
5147                                         sections[i].size);
5148     }
5149
5150         // count external symbols defined here
5151     oc->n_symbols = 0;
5152     if(symLC)
5153     {
5154         for(i=0;i<symLC->nsyms;i++)
5155         {
5156             if(nlist[i].n_type & N_STAB)
5157                 ;
5158             else if(nlist[i].n_type & N_EXT)
5159             {
5160                 if((nlist[i].n_type & N_TYPE) == N_UNDF
5161                     && (nlist[i].n_value != 0))
5162                 {
5163                     commonSize += nlist[i].n_value;
5164                     oc->n_symbols++;
5165                 }
5166                 else if((nlist[i].n_type & N_TYPE) == N_SECT)
5167                     oc->n_symbols++;
5168             }
5169         }
5170     }
5171     IF_DEBUG(linker, debugBelch("ocGetNames_MachO: %d external symbols\n", oc->n_symbols));
5172     oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
5173                                    "ocGetNames_MachO(oc->symbols)");
5174
5175     if(symLC)
5176     {
5177         for(i=0;i<symLC->nsyms;i++)
5178         {
5179             if(nlist[i].n_type & N_STAB)
5180                 ;
5181             else if((nlist[i].n_type & N_TYPE) == N_SECT)
5182             {
5183                 if(nlist[i].n_type & N_EXT)
5184                 {
5185                     char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
5186                     if ((nlist[i].n_desc & N_WEAK_DEF) && lookupSymbol(nm)) {
5187                         // weak definition, and we already have a definition
5188                         IF_DEBUG(linker, debugBelch("    weak: %s\n", nm));
5189                     }
5190                     else
5191                     {
5192                             IF_DEBUG(linker, debugBelch("ocGetNames_MachO: inserting %s\n", nm));
5193                             ghciInsertStrHashTable(oc->fileName, symhash, nm,
5194                                                     image
5195                                                     + sections[nlist[i].n_sect-1].offset
5196                                                     - sections[nlist[i].n_sect-1].addr
5197                                                     + nlist[i].n_value);
5198                             oc->symbols[curSymbol++] = nm;
5199                     }
5200                 }
5201             }
5202         }
5203     }
5204
5205     commonStorage = stgCallocBytes(1,commonSize,"ocGetNames_MachO(common symbols)");
5206     commonCounter = (unsigned long)commonStorage;
5207     if(symLC)
5208     {
5209         for(i=0;i<symLC->nsyms;i++)
5210         {
5211             if((nlist[i].n_type & N_TYPE) == N_UNDF
5212                     && (nlist[i].n_type & N_EXT) && (nlist[i].n_value != 0))
5213             {
5214                 char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
5215                 unsigned long sz = nlist[i].n_value;
5216
5217                 nlist[i].n_value = commonCounter;
5218
5219                 IF_DEBUG(linker, debugBelch("ocGetNames_MachO: inserting common symbol: %s\n", nm));
5220                 ghciInsertStrHashTable(oc->fileName, symhash, nm,
5221                                        (void*)commonCounter);
5222                 oc->symbols[curSymbol++] = nm;
5223
5224                 commonCounter += sz;
5225             }
5226         }
5227     }
5228     return 1;
5229 }
5230
5231 static int ocResolve_MachO(ObjectCode* oc)
5232 {
5233     char *image = (char*) oc->image;
5234     struct mach_header *header = (struct mach_header*) image;
5235     struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
5236     unsigned i;
5237     struct segment_command *segLC = NULL;
5238     struct section *sections;
5239     struct symtab_command *symLC = NULL;
5240     struct dysymtab_command *dsymLC = NULL;
5241     struct nlist *nlist;
5242
5243     IF_DEBUG(linker, debugBelch("ocResolve_MachO: start\n"));
5244     for (i = 0; i < header->ncmds; i++)
5245     {
5246         if(lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64)
5247             segLC = (struct segment_command*) lc;
5248         else if(lc->cmd == LC_SYMTAB)
5249             symLC = (struct symtab_command*) lc;
5250         else if(lc->cmd == LC_DYSYMTAB)
5251             dsymLC = (struct dysymtab_command*) lc;
5252         lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
5253     }
5254
5255     sections = (struct section*) (segLC+1);
5256     nlist = symLC ? (struct nlist*) (image + symLC->symoff)
5257                   : NULL;
5258
5259     if(dsymLC)
5260     {
5261         unsigned long *indirectSyms
5262             = (unsigned long*) (image + dsymLC->indirectsymoff);
5263
5264         IF_DEBUG(linker, debugBelch("ocResolve_MachO: resolving dsymLC\n"));
5265         for (i = 0; i < segLC->nsects; i++)
5266         {
5267             if(    !strcmp(sections[i].sectname,"__la_symbol_ptr")
5268                 || !strcmp(sections[i].sectname,"__la_sym_ptr2")
5269                 || !strcmp(sections[i].sectname,"__la_sym_ptr3"))
5270             {
5271                 if(!resolveImports(oc,image,symLC,&sections[i],indirectSyms,nlist))
5272                     return 0;
5273             }
5274             else if(!strcmp(sections[i].sectname,"__nl_symbol_ptr")
5275                 ||  !strcmp(sections[i].sectname,"__pointers"))
5276             {
5277                 if(!resolveImports(oc,image,symLC,&sections[i],indirectSyms,nlist))
5278                     return 0;
5279             }
5280             else if(!strcmp(sections[i].sectname,"__jump_table"))
5281             {
5282                 if(!resolveImports(oc,image,symLC,&sections[i],indirectSyms,nlist))
5283                     return 0;
5284             }
5285             else
5286             {
5287                 IF_DEBUG(linker, debugBelch("ocResolve_MachO: unknown section\n"));
5288             }
5289         }
5290     }
5291
5292     for(i=0;i<segLC->nsects;i++)
5293     {
5294             IF_DEBUG(linker, debugBelch("ocResolve_MachO: relocating section %d\n", i));
5295
5296         if (!relocateSection(oc,image,symLC,nlist,segLC->nsects,sections,&sections[i]))
5297             return 0;
5298     }
5299
5300 #if defined (powerpc_HOST_ARCH)
5301     ocFlushInstructionCache( oc );
5302 #endif
5303
5304     return 1;
5305 }
5306
5307 #ifdef powerpc_HOST_ARCH
5308 /*
5309  * The Mach-O object format uses leading underscores. But not everywhere.
5310  * There is a small number of runtime support functions defined in
5311  * libcc_dynamic.a whose name does not have a leading underscore.
5312  * As a consequence, we can't get their address from C code.
5313  * We have to use inline assembler just to take the address of a function.
5314  * Yuck.
5315  */
5316
5317 extern void* symbolsWithoutUnderscore[];
5318
5319 static void machoInitSymbolsWithoutUnderscore()
5320 {
5321     void **p = symbolsWithoutUnderscore;
5322     __asm__ volatile(".globl _symbolsWithoutUnderscore\n.data\n_symbolsWithoutUnderscore:");
5323
5324 #undef SymI_NeedsProto
5325 #define SymI_NeedsProto(x)  \
5326     __asm__ volatile(".long " # x);
5327
5328     RTS_MACHO_NOUNDERLINE_SYMBOLS
5329
5330     __asm__ volatile(".text");
5331
5332 #undef SymI_NeedsProto
5333 #define SymI_NeedsProto(x)  \
5334     ghciInsertStrHashTable("(GHCi built-in symbols)", symhash, #x, *p++);
5335
5336     RTS_MACHO_NOUNDERLINE_SYMBOLS
5337
5338 #undef SymI_NeedsProto
5339 }
5340 #endif
5341
5342 #ifndef USE_MMAP
5343 /*
5344  * Figure out by how much to shift the entire Mach-O file in memory
5345  * when loading so that its single segment ends up 16-byte-aligned
5346  */
5347 static int machoGetMisalignment( FILE * f )
5348 {
5349     struct mach_header header;
5350     int misalignment;
5351
5352     {
5353         int n = fread(&header, sizeof(header), 1, f);
5354         if (n != 1) {
5355             barf("machoGetMisalignment: can't read the Mach-O header");
5356         }
5357     }
5358     fseek(f, -sizeof(header), SEEK_CUR);
5359
5360 #if x86_64_HOST_ARCH || powerpc64_HOST_ARCH
5361     if(header.magic != MH_MAGIC_64) {
5362         barf("Bad magic. Expected: %08x, got: %08x.",
5363              MH_MAGIC_64, header.magic);
5364     }
5365 #else
5366     if(header.magic != MH_MAGIC) {
5367         barf("Bad magic. Expected: %08x, got: %08x.",
5368              MH_MAGIC, header.magic);
5369     }
5370 #endif
5371
5372     misalignment = (header.sizeofcmds + sizeof(header))
5373                     & 0xF;
5374
5375     return misalignment ? (16 - misalignment) : 0;
5376 }
5377 #endif
5378
5379 #endif