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 "RtsFlags.h"
  22 #include "HsFFI.h"
  23 #include "Hash.h"
  24 #include "Linker.h"
  25 #include "LinkerInternals.h"
  26 #include "RtsUtils.h"
  27 #include "Schedule.h"
  28 #include "Sparks.h"
  29 #include "RtsGlobals.h"
  30 #include "Timer.h"
  31 #include "Trace.h"
  32
  33 #ifdef HAVE_SYS_TYPES_H
  34 #include <sys/types.h>
  35 #endif
  36
  37 #include <stdlib.h>
  38 #include <string.h>
  39
  40 #ifdef HAVE_SYS_STAT_H
  41 #include <sys/stat.h>
  42 #endif
  43
  44 #if defined(HAVE_DLFCN_H)
  45 #include <dlfcn.h>
  46 #endif
  47
  48 #if defined(cygwin32_HOST_OS)
  49 #ifdef HAVE_DIRENT_H
  50 #include <dirent.h>
  51 #endif
  52
  53 #ifdef HAVE_SYS_TIME_H
  54 #include <sys/time.h>
  55 #endif
  56 #include <regex.h>
  57 #include <sys/fcntl.h>
  58 #include <sys/termios.h>
  59 #include <sys/utime.h>
  60 #include <sys/utsname.h>
  61 #include <sys/wait.h>
  62 #endif
  63
  64 #if defined(ia64_HOST_ARCH) || defined(linux_HOST_OS) || defined(freebsd_HOST_OS) || defined(netbsd_HOST_OS) || defined(openbsd_HOST_OS)
  65 #define USE_MMAP
  66 #include <fcntl.h>
  67 #include <sys/mman.h>
  68
  69 #if defined(linux_HOST_OS) || defined(freebsd_HOST_OS) || defined(netbsd_HOST_OS) || defined(openbsd_HOST_OS)
  70 #ifdef HAVE_UNISTD_H
  71 #include <unistd.h>
  72 #endif
  73 #endif
  74
  75 #endif
  76
  77 #if defined(linux_HOST_OS) || defined(solaris2_HOST_OS) || defined(freebsd_HOST_OS) || defined(netbsd_HOST_OS) || defined(openbsd_HOST_OS)
  78 #  define OBJFORMAT_ELF
  79 #elif defined(cygwin32_HOST_OS) || defined (mingw32_HOST_OS)
  80 #  define OBJFORMAT_PEi386
  81 #  include <windows.h>
  82 #  include <math.h>
  83 #elif defined(darwin_HOST_OS)
  84 #  define OBJFORMAT_MACHO
  85 #  include <mach-o/loader.h>
  86 #  include <mach-o/nlist.h>
  87 #  include <mach-o/reloc.h>
  88 #if !defined(HAVE_DLFCN_H)
  89 #  include <mach-o/dyld.h>
  90 #endif
  91 #if defined(powerpc_HOST_ARCH)
  92 #  include <mach-o/ppc/reloc.h>
  93 #endif
  94 #if defined(x86_64_HOST_ARCH)
  95 #  include <mach-o/x86_64/reloc.h>
  96 #endif
  97 #endif
  98
  99 /* Hash table mapping symbol names to Symbol */
 100 static /*Str*/HashTable *symhash;
 101
 102 /* Hash table mapping symbol names to StgStablePtr */
 103 static /*Str*/HashTable *stablehash;
 104
 105 /* List of currently loaded objects */
 106 ObjectCode *objects = NULL;     /* initially empty */
 107
 108 #if defined(OBJFORMAT_ELF)
 109 static int ocVerifyImage_ELF    ( ObjectCode* oc );
 110 static int ocGetNames_ELF       ( ObjectCode* oc );
 111 static int ocResolve_ELF        ( ObjectCode* oc );
 112 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
 113 static int ocAllocateSymbolExtras_ELF ( ObjectCode* oc );
 114 #endif
 115 #elif defined(OBJFORMAT_PEi386)
 116 static int ocVerifyImage_PEi386 ( ObjectCode* oc );
 117 static int ocGetNames_PEi386    ( ObjectCode* oc );
 118 static int ocResolve_PEi386     ( ObjectCode* oc );
 119 static void *lookupSymbolInDLLs ( unsigned char *lbl );
 120 static void zapTrailingAtSign   ( unsigned char *sym );
 121 #elif defined(OBJFORMAT_MACHO)
 122 static int ocVerifyImage_MachO    ( ObjectCode* oc );
 123 static int ocGetNames_MachO       ( ObjectCode* oc );
 124 static int ocResolve_MachO        ( ObjectCode* oc );
 125
 126 static int machoGetMisalignment( FILE * );
 127 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
 128 static int ocAllocateSymbolExtras_MachO ( ObjectCode* oc );
 129 #endif
 130 #ifdef powerpc_HOST_ARCH
 131 static void machoInitSymbolsWithoutUnderscore( void );
 132 #endif
 133 #endif
 134
 135 /* on x86_64 we have a problem with relocating symbol references in
 136  * code that was compiled without -fPIC.  By default, the small memory
 137  * model is used, which assumes that symbol references can fit in a
 138  * 32-bit slot.  The system dynamic linker makes this work for
 139  * references to shared libraries by either (a) allocating a jump
 140  * table slot for code references, or (b) moving the symbol at load
 141  * time (and copying its contents, if necessary) for data references.
 142  *
 143  * We unfortunately can't tell whether symbol references are to code
 144  * or data.  So for now we assume they are code (the vast majority
 145  * are), and allocate jump-table slots.  Unfortunately this will
 146  * SILENTLY generate crashing code for data references.  This hack is
 147  * enabled by X86_64_ELF_NONPIC_HACK.
 148  *
 149  * One workaround is to use shared Haskell libraries.  This is
 150  * coming.  Another workaround is to keep the static libraries but
 151  * compile them with -fPIC, because that will generate PIC references
 152  * to data which can be relocated.  The PIC code is still too green to
 153  * do this systematically, though.
 154  *
 155  * See bug #781
 156  * See thread http://www.haskell.org/pipermail/cvs-ghc/2007-September/038458.html
 157  *
 158  * Naming Scheme for Symbol Macros
 159  *
 160  * SymI_*: symbol is internal to the RTS. It resides in an object
 161  *         file/library that is statically.
 162  * SymE_*: symbol is external to the RTS library. It might be linked
 163  *         dynamically.
 164  *
 165  * Sym*_HasProto  : the symbol prototype is imported in an include file
 166  *                  or defined explicitly
 167  * Sym*_NeedsProto: the symbol is undefined and we add a dummy
 168  *                  default proto extern void sym(void);
 169  */
 170 #define X86_64_ELF_NONPIC_HACK 1
 171
 172 /* Link objects into the lower 2Gb on x86_64.  GHC assumes the
 173  * small memory model on this architecture (see gcc docs,
 174  * -mcmodel=small).
 175  *
 176  * MAP_32BIT not available on OpenBSD/amd64
 177  */
 178 #if defined(x86_64_HOST_ARCH) && defined(MAP_32BIT)
 179 #define TRY_MAP_32BIT MAP_32BIT
 180 #else
 181 #define TRY_MAP_32BIT 0
 182 #endif
 183
 184 /*
 185  * Due to the small memory model (see above), on x86_64 we have to map
 186  * all our non-PIC object files into the low 2Gb of the address space
 187  * (why 2Gb and not 4Gb?  Because all addresses must be reachable
 188  * using a 32-bit signed PC-relative offset). On Linux we can do this
 189  * using the MAP_32BIT flag to mmap(), however on other OSs
 190  * (e.g. *BSD, see #2063, and also on Linux inside Xen, see #2512), we
 191  * can't do this.  So on these systems, we have to pick a base address
 192  * in the low 2Gb of the address space and try to allocate memory from
 193  * there.
 194  *
 195  * We pick a default address based on the OS, but also make this
 196  * configurable via an RTS flag (+RTS -xm)
 197  */
 198 #if defined(x86_64_HOST_ARCH)
 199
 200 #if defined(MAP_32BIT)
 201 // Try to use MAP_32BIT
 202 #define MMAP_32BIT_BASE_DEFAULT 0
 203 #else
 204 // A guess: 1Gb.
 205 #define MMAP_32BIT_BASE_DEFAULT 0x40000000
 206 #endif
 207
 208 static void *mmap_32bit_base = (void *)MMAP_32BIT_BASE_DEFAULT;
 209 #endif
 210
 211 /* MAP_ANONYMOUS is MAP_ANON on some systems, e.g. OpenBSD */
 212 #if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
 213 #define MAP_ANONYMOUS MAP_ANON
 214 #endif
 215
 216 /* -----------------------------------------------------------------------------
 217  * Built-in symbols from the RTS
 218  */
 219
 220 typedef struct _RtsSymbolVal {
 221     char   *lbl;
 222     void   *addr;
 223 } RtsSymbolVal;
 224
 225 #define Maybe_Stable_Names      SymI_HasProto(mkWeakzh_fast)                    \
 226                                 SymI_HasProto(mkWeakForeignEnvzh_fast)          \
 227                                 SymI_HasProto(makeStableNamezh_fast)            \
 228                                 SymI_HasProto(finalizzeWeakzh_fast)
 229
 230 #if !defined (mingw32_HOST_OS)
 231 #define RTS_POSIX_ONLY_SYMBOLS                  \
 232       SymI_HasProto(shutdownHaskellAndSignal)   \
 233       SymI_NeedsProto(lockFile)                 \
 234       SymI_NeedsProto(unlockFile)               \
 235       SymI_HasProto(signal_handlers)            \
 236       SymI_HasProto(stg_sig_install)            \
 237       SymI_NeedsProto(nocldstop)
 238 #endif
 239
 240 #if defined (cygwin32_HOST_OS)
 241 #define RTS_MINGW_ONLY_SYMBOLS /**/
 242 /* Don't have the ability to read import libs / archives, so
 243  * we have to stupidly list a lot of what libcygwin.a
 244  * exports; sigh.
 245  */
 246 #define RTS_CYGWIN_ONLY_SYMBOLS                          \
 247       SymI_HasProto(regfree)                             \
 248       SymI_HasProto(regexec)                             \
 249       SymI_HasProto(regerror)                            \
 250       SymI_HasProto(regcomp)                             \
 251       SymI_HasProto(__errno)                             \
 252       SymI_HasProto(access)                              \
 253       SymI_HasProto(chmod)                               \
 254       SymI_HasProto(chdir)                               \
 255       SymI_HasProto(close)                               \
 256       SymI_HasProto(creat)                               \
 257       SymI_HasProto(dup)                                 \
 258       SymI_HasProto(dup2)                                \
 259       SymI_HasProto(fstat)                               \
 260       SymI_HasProto(fcntl)                               \
 261       SymI_HasProto(getcwd)                              \
 262       SymI_HasProto(getenv)                              \
 263       SymI_HasProto(lseek)                               \
 264       SymI_HasProto(open)                                \
 265       SymI_HasProto(fpathconf)                           \
 266       SymI_HasProto(pathconf)                            \
 267       SymI_HasProto(stat)                                \
 268       SymI_HasProto(pow)                                 \
 269       SymI_HasProto(tanh)                                \
 270       SymI_HasProto(cosh)                                \
 271       SymI_HasProto(sinh)                                \
 272       SymI_HasProto(atan)                                \
 273       SymI_HasProto(acos)                                \
 274       SymI_HasProto(asin)                                \
 275       SymI_HasProto(tan)                                 \
 276       SymI_HasProto(cos)                                 \
 277       SymI_HasProto(sin)                                 \
 278       SymI_HasProto(exp)                                 \
 279       SymI_HasProto(log)                                 \
 280       SymI_HasProto(sqrt)                                \
 281       SymI_HasProto(localtime_r)                         \
 282       SymI_HasProto(gmtime_r)                            \
 283       SymI_HasProto(mktime)                              \
 284       SymI_NeedsProto(_imp___tzname)                     \
 285       SymI_HasProto(gettimeofday)                        \
 286       SymI_HasProto(timezone)                            \
 287       SymI_HasProto(tcgetattr)                           \
 288       SymI_HasProto(tcsetattr)                           \
 289       SymI_HasProto(memcpy)                              \
 290       SymI_HasProto(memmove)                             \
 291       SymI_HasProto(realloc)                             \
 292       SymI_HasProto(malloc)                              \
 293       SymI_HasProto(free)                                \
 294       SymI_HasProto(fork)                                \
 295       SymI_HasProto(lstat)                               \
 296       SymI_HasProto(isatty)                              \
 297       SymI_HasProto(mkdir)                               \
 298       SymI_HasProto(opendir)                             \
 299       SymI_HasProto(readdir)                             \
 300       SymI_HasProto(rewinddir)                           \
 301       SymI_HasProto(closedir)                            \
 302       SymI_HasProto(link)                                \
 303       SymI_HasProto(mkfifo)                              \
 304       SymI_HasProto(pipe)                                \
 305       SymI_HasProto(read)                                \
 306       SymI_HasProto(rename)                              \
 307       SymI_HasProto(rmdir)                               \
 308       SymI_HasProto(select)                              \
 309       SymI_HasProto(system)                              \
 310       SymI_HasProto(write)                               \
 311       SymI_HasProto(strcmp)                              \
 312       SymI_HasProto(strcpy)                              \
 313       SymI_HasProto(strncpy)                             \
 314       SymI_HasProto(strerror)                            \
 315       SymI_HasProto(sigaddset)                           \
 316       SymI_HasProto(sigemptyset)                         \
 317       SymI_HasProto(sigprocmask)                         \
 318       SymI_HasProto(umask)                               \
 319       SymI_HasProto(uname)                               \
 320       SymI_HasProto(unlink)                              \
 321       SymI_HasProto(utime)                               \
 322       SymI_HasProto(waitpid)
 323
 324 #elif !defined(mingw32_HOST_OS)
 325 #define RTS_MINGW_ONLY_SYMBOLS /**/
 326 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
 327 #else /* defined(mingw32_HOST_OS) */
 328 #define RTS_POSIX_ONLY_SYMBOLS  /**/
 329 #define RTS_CYGWIN_ONLY_SYMBOLS /**/
 330
 331 /* Extra syms gen'ed by mingw-2's gcc-3.2: */
 332 #if __GNUC__>=3
 333 #define RTS_MINGW_EXTRA_SYMS                    \
 334       SymI_NeedsProto(_imp____mb_cur_max)       \
 335       SymI_NeedsProto(_imp___pctype)
 336 #else
 337 #define RTS_MINGW_EXTRA_SYMS
 338 #endif
 339
 340 #if HAVE_GETTIMEOFDAY
 341 #define RTS_MINGW_GETTIMEOFDAY_SYM SymI_NeedsProto(gettimeofday)
 342 #else
 343 #define RTS_MINGW_GETTIMEOFDAY_SYM /**/
 344 #endif
 345
 346 /* These are statically linked from the mingw libraries into the ghc
 347    executable, so we have to employ this hack. */
 348 #define RTS_MINGW_ONLY_SYMBOLS                           \
 349       SymI_HasProto(asyncReadzh_fast)                    \
 350       SymI_HasProto(asyncWritezh_fast)                   \
 351       SymI_HasProto(asyncDoProczh_fast)                  \
 352       SymI_HasProto(memset)                              \
 353       SymI_HasProto(inet_ntoa)                           \
 354       SymI_HasProto(inet_addr)                           \
 355       SymI_HasProto(htonl)                               \
 356       SymI_HasProto(recvfrom)                            \
 357       SymI_HasProto(listen)                              \
 358       SymI_HasProto(bind)                                \
 359       SymI_HasProto(shutdown)                            \
 360       SymI_HasProto(connect)                             \
 361       SymI_HasProto(htons)                               \
 362       SymI_HasProto(ntohs)                               \
 363       SymI_HasProto(getservbyname)                       \
 364       SymI_HasProto(getservbyport)                       \
 365       SymI_HasProto(getprotobynumber)                    \
 366       SymI_HasProto(getprotobyname)                      \
 367       SymI_HasProto(gethostbyname)                       \
 368       SymI_HasProto(gethostbyaddr)                       \
 369       SymI_HasProto(gethostname)                         \
 370       SymI_HasProto(strcpy)                              \
 371       SymI_HasProto(strncpy)                             \
 372       SymI_HasProto(abort)                               \
 373       SymI_NeedsProto(_alloca)                           \
 374       SymI_NeedsProto(isxdigit)                          \
 375       SymI_NeedsProto(isupper)                           \
 376       SymI_NeedsProto(ispunct)                           \
 377       SymI_NeedsProto(islower)                           \
 378       SymI_NeedsProto(isspace)                           \
 379       SymI_NeedsProto(isprint)                           \
 380       SymI_NeedsProto(isdigit)                           \
 381       SymI_NeedsProto(iscntrl)                           \
 382       SymI_NeedsProto(isalpha)                           \
 383       SymI_NeedsProto(isalnum)                           \
 384       SymI_NeedsProto(isascii)                           \
 385       SymI_HasProto(__mingw_vfprintf)                    \
 386       SymI_HasProto(strcmp)                              \
 387       SymI_HasProto(memmove)                             \
 388       SymI_HasProto(realloc)                             \
 389       SymI_HasProto(malloc)                              \
 390       SymI_HasProto(pow)                                 \
 391       SymI_HasProto(tanh)                                \
 392       SymI_HasProto(cosh)                                \
 393       SymI_HasProto(sinh)                                \
 394       SymI_HasProto(atan)                                \
 395       SymI_HasProto(acos)                                \
 396       SymI_HasProto(asin)                                \
 397       SymI_HasProto(tan)                                 \
 398       SymI_HasProto(cos)                                 \
 399       SymI_HasProto(sin)                                 \
 400       SymI_HasProto(exp)                                 \
 401       SymI_HasProto(log)                                 \
 402       SymI_HasProto(sqrt)                                \
 403       SymI_HasProto(powf)                                \
 404       SymI_HasProto(tanhf)                               \
 405       SymI_HasProto(coshf)                               \
 406       SymI_HasProto(sinhf)                               \
 407       SymI_HasProto(atanf)                               \
 408       SymI_HasProto(acosf)                               \
 409       SymI_HasProto(asinf)                               \
 410       SymI_HasProto(tanf)                                \
 411       SymI_HasProto(cosf)                                \
 412       SymI_HasProto(sinf)                                \
 413       SymI_HasProto(expf)                                \
 414       SymI_HasProto(logf)                                \
 415       SymI_HasProto(sqrtf)                               \
 416       SymI_HasProto(memcpy)                              \
 417       SymI_HasProto(rts_InstallConsoleEvent)             \
 418       SymI_HasProto(rts_ConsoleHandlerDone)              \
 419       SymI_NeedsProto(mktime)                            \
 420       SymI_NeedsProto(_imp___timezone)                   \
 421       SymI_NeedsProto(_imp___tzname)                     \
 422       SymI_NeedsProto(_imp__tzname)                      \
 423       SymI_NeedsProto(_imp___iob)                        \
 424       SymI_NeedsProto(_imp___osver)                      \
 425       SymI_NeedsProto(localtime)                         \
 426       SymI_NeedsProto(gmtime)                            \
 427       SymI_NeedsProto(opendir)                           \
 428       SymI_NeedsProto(readdir)                           \
 429       SymI_NeedsProto(rewinddir)                         \
 430       RTS_MINGW_EXTRA_SYMS                               \
 431       RTS_MINGW_GETTIMEOFDAY_SYM                         \
 432       SymI_NeedsProto(closedir)
 433 #endif
 434
 435 #if defined(darwin_TARGET_OS) && HAVE_PRINTF_LDBLSTUB
 436 #define RTS_DARWIN_ONLY_SYMBOLS                             \
 437      SymI_NeedsProto(asprintf$LDBLStub)                     \
 438      SymI_NeedsProto(err$LDBLStub)                          \
 439      SymI_NeedsProto(errc$LDBLStub)                         \
 440      SymI_NeedsProto(errx$LDBLStub)                         \
 441      SymI_NeedsProto(fprintf$LDBLStub)                      \
 442      SymI_NeedsProto(fscanf$LDBLStub)                       \
 443      SymI_NeedsProto(fwprintf$LDBLStub)                     \
 444      SymI_NeedsProto(fwscanf$LDBLStub)                      \
 445      SymI_NeedsProto(printf$LDBLStub)                       \
 446      SymI_NeedsProto(scanf$LDBLStub)                        \
 447      SymI_NeedsProto(snprintf$LDBLStub)                     \
 448      SymI_NeedsProto(sprintf$LDBLStub)                      \
 449      SymI_NeedsProto(sscanf$LDBLStub)                       \
 450      SymI_NeedsProto(strtold$LDBLStub)                      \
 451      SymI_NeedsProto(swprintf$LDBLStub)                     \
 452      SymI_NeedsProto(swscanf$LDBLStub)                      \
 453      SymI_NeedsProto(syslog$LDBLStub)                       \
 454      SymI_NeedsProto(vasprintf$LDBLStub)                    \
 455      SymI_NeedsProto(verr$LDBLStub)                         \
 456      SymI_NeedsProto(verrc$LDBLStub)                        \
 457      SymI_NeedsProto(verrx$LDBLStub)                        \
 458      SymI_NeedsProto(vfprintf$LDBLStub)                     \
 459      SymI_NeedsProto(vfscanf$LDBLStub)                      \
 460      SymI_NeedsProto(vfwprintf$LDBLStub)                    \
 461      SymI_NeedsProto(vfwscanf$LDBLStub)                     \
 462      SymI_NeedsProto(vprintf$LDBLStub)                      \
 463      SymI_NeedsProto(vscanf$LDBLStub)                       \
 464      SymI_NeedsProto(vsnprintf$LDBLStub)                    \
 465      SymI_NeedsProto(vsprintf$LDBLStub)                     \
 466      SymI_NeedsProto(vsscanf$LDBLStub)                      \
 467      SymI_NeedsProto(vswprintf$LDBLStub)                    \
 468      SymI_NeedsProto(vswscanf$LDBLStub)                     \
 469      SymI_NeedsProto(vsyslog$LDBLStub)                      \
 470      SymI_NeedsProto(vwarn$LDBLStub)                        \
 471      SymI_NeedsProto(vwarnc$LDBLStub)                       \
 472      SymI_NeedsProto(vwarnx$LDBLStub)                       \
 473      SymI_NeedsProto(vwprintf$LDBLStub)                     \
 474      SymI_NeedsProto(vwscanf$LDBLStub)                      \
 475      SymI_NeedsProto(warn$LDBLStub)                         \
 476      SymI_NeedsProto(warnc$LDBLStub)                        \
 477      SymI_NeedsProto(warnx$LDBLStub)                        \
 478      SymI_NeedsProto(wcstold$LDBLStub)                      \
 479      SymI_NeedsProto(wprintf$LDBLStub)                      \
 480      SymI_NeedsProto(wscanf$LDBLStub)
 481 #else
 482 #define RTS_DARWIN_ONLY_SYMBOLS
 483 #endif
 484
 485 #ifndef SMP
 486 # define MAIN_CAP_SYM SymI_HasProto(MainCapability)
 487 #else
 488 # define MAIN_CAP_SYM
 489 #endif
 490
 491 #if !defined(mingw32_HOST_OS)
 492 #define RTS_USER_SIGNALS_SYMBOLS \
 493    SymI_HasProto(setIOManagerPipe) \
 494    SymI_NeedsProto(blockUserSignals) \
 495    SymI_NeedsProto(unblockUserSignals)
 496 #else
 497 #define RTS_USER_SIGNALS_SYMBOLS     \
 498    SymI_HasProto(sendIOManagerEvent) \
 499    SymI_HasProto(readIOManagerEvent) \
 500    SymI_HasProto(getIOManagerEvent)  \
 501    SymI_HasProto(console_handler)
 502 #endif
 503
 504 #define RTS_LIBFFI_SYMBOLS                                  \
 505      SymE_NeedsProto(ffi_prep_cif)                          \
 506      SymE_NeedsProto(ffi_call)                              \
 507      SymE_NeedsProto(ffi_type_void)                         \
 508      SymE_NeedsProto(ffi_type_float)                        \
 509      SymE_NeedsProto(ffi_type_double)                       \
 510      SymE_NeedsProto(ffi_type_sint64)                       \
 511      SymE_NeedsProto(ffi_type_uint64)                       \
 512      SymE_NeedsProto(ffi_type_sint32)                       \
 513      SymE_NeedsProto(ffi_type_uint32)                       \
 514      SymE_NeedsProto(ffi_type_sint16)                       \
 515      SymE_NeedsProto(ffi_type_uint16)                       \
 516      SymE_NeedsProto(ffi_type_sint8)                        \
 517      SymE_NeedsProto(ffi_type_uint8)                        \
 518      SymE_NeedsProto(ffi_type_pointer)
 519
 520 #ifdef TABLES_NEXT_TO_CODE
 521 #define RTS_RET_SYMBOLS /* nothing */
 522 #else
 523 #define RTS_RET_SYMBOLS                                 \
 524       SymI_HasProto(stg_enter_ret)                      \
 525       SymI_HasProto(stg_gc_fun_ret)                     \
 526       SymI_HasProto(stg_ap_v_ret)                       \
 527       SymI_HasProto(stg_ap_f_ret)                       \
 528       SymI_HasProto(stg_ap_d_ret)                       \
 529       SymI_HasProto(stg_ap_l_ret)                       \
 530       SymI_HasProto(stg_ap_n_ret)                       \
 531       SymI_HasProto(stg_ap_p_ret)                       \
 532       SymI_HasProto(stg_ap_pv_ret)                      \
 533       SymI_HasProto(stg_ap_pp_ret)                      \
 534       SymI_HasProto(stg_ap_ppv_ret)                     \
 535       SymI_HasProto(stg_ap_ppp_ret)                     \
 536       SymI_HasProto(stg_ap_pppv_ret)                    \
 537       SymI_HasProto(stg_ap_pppp_ret)                    \
 538       SymI_HasProto(stg_ap_ppppp_ret)                   \
 539       SymI_HasProto(stg_ap_pppppp_ret)
 540 #endif
 541
 542 #define RTS_SYMBOLS                                     \
 543       Maybe_Stable_Names                                \
 544       SymI_HasProto(StgReturn)                          \
 545       SymI_HasProto(stg_enter_info)                     \
 546       SymI_HasProto(stg_gc_void_info)                   \
 547       SymI_HasProto(__stg_gc_enter_1)                   \
 548       SymI_HasProto(stg_gc_noregs)                      \
 549       SymI_HasProto(stg_gc_unpt_r1_info)                \
 550       SymI_HasProto(stg_gc_unpt_r1)                     \
 551       SymI_HasProto(stg_gc_unbx_r1_info)                \
 552       SymI_HasProto(stg_gc_unbx_r1)                     \
 553       SymI_HasProto(stg_gc_f1_info)                     \
 554       SymI_HasProto(stg_gc_f1)                          \
 555       SymI_HasProto(stg_gc_d1_info)                     \
 556       SymI_HasProto(stg_gc_d1)                          \
 557       SymI_HasProto(stg_gc_l1_info)                     \
 558       SymI_HasProto(stg_gc_l1)                          \
 559       SymI_HasProto(__stg_gc_fun)                       \
 560       SymI_HasProto(stg_gc_fun_info)                    \
 561       SymI_HasProto(stg_gc_gen)                         \
 562       SymI_HasProto(stg_gc_gen_info)                    \
 563       SymI_HasProto(stg_gc_gen_hp)                      \
 564       SymI_HasProto(stg_gc_ut)                          \
 565       SymI_HasProto(stg_gen_yield)                      \
 566       SymI_HasProto(stg_yield_noregs)                   \
 567       SymI_HasProto(stg_yield_to_interpreter)           \
 568       SymI_HasProto(stg_gen_block)                      \
 569       SymI_HasProto(stg_block_noregs)                   \
 570       SymI_HasProto(stg_block_1)                        \
 571       SymI_HasProto(stg_block_takemvar)                 \
 572       SymI_HasProto(stg_block_putmvar)                  \
 573       MAIN_CAP_SYM                                      \
 574       SymI_HasProto(MallocFailHook)                     \
 575       SymI_HasProto(OnExitHook)                         \
 576       SymI_HasProto(OutOfHeapHook)                      \
 577       SymI_HasProto(StackOverflowHook)                  \
 578       SymI_HasProto(addDLL)                             \
 579       SymI_HasProto(__int_encodeDouble)                 \
 580       SymI_HasProto(__word_encodeDouble)                \
 581       SymI_HasProto(__2Int_encodeDouble)                \
 582       SymI_HasProto(__int_encodeFloat)                  \
 583       SymI_HasProto(__word_encodeFloat)                 \
 584       SymI_HasProto(atomicallyzh_fast)                  \
 585       SymI_HasProto(barf)                               \
 586       SymI_HasProto(debugBelch)                         \
 587       SymI_HasProto(errorBelch)                         \
 588       SymI_HasProto(sysErrorBelch)                      \
 589       SymI_HasProto(asyncExceptionsBlockedzh_fast)      \
 590       SymI_HasProto(blockAsyncExceptionszh_fast)        \
 591       SymI_HasProto(catchzh_fast)                       \
 592       SymI_HasProto(catchRetryzh_fast)                  \
 593       SymI_HasProto(catchSTMzh_fast)                    \
 594       SymI_HasProto(checkzh_fast)                       \
 595       SymI_HasProto(closure_flags)                      \
 596       SymI_HasProto(cmp_thread)                         \
 597       SymI_HasProto(createAdjustor)                     \
 598       SymI_HasProto(decodeDoublezu2Intzh_fast)          \
 599       SymI_HasProto(decodeFloatzuIntzh_fast)            \
 600       SymI_HasProto(defaultsHook)                       \
 601       SymI_HasProto(delayzh_fast)                       \
 602       SymI_HasProto(deRefWeakzh_fast)                   \
 603       SymI_HasProto(deRefStablePtrzh_fast)              \
 604       SymI_HasProto(dirty_MUT_VAR)                      \
 605       SymI_HasProto(forkzh_fast)                        \
 606       SymI_HasProto(forkOnzh_fast)                      \
 607       SymI_HasProto(forkProcess)                        \
 608       SymI_HasProto(forkOS_createThread)                \
 609       SymI_HasProto(freeHaskellFunctionPtr)             \
 610       SymI_HasProto(freeStablePtr)                      \
 611       SymI_HasProto(getOrSetTypeableStore)              \
 612       SymI_HasProto(getOrSetSignalHandlerStore)         \
 613       SymI_HasProto(genSymZh)                           \
 614       SymI_HasProto(genericRaise)                       \
 615       SymI_HasProto(getProgArgv)                        \
 616       SymI_HasProto(getFullProgArgv)                    \
 617       SymI_HasProto(getStablePtr)                       \
 618       SymI_HasProto(hs_init)                            \
 619       SymI_HasProto(hs_exit)                            \
 620       SymI_HasProto(hs_set_argv)                        \
 621       SymI_HasProto(hs_add_root)                        \
 622       SymI_HasProto(hs_perform_gc)                      \
 623       SymI_HasProto(hs_free_stable_ptr)                 \
 624       SymI_HasProto(hs_free_fun_ptr)                    \
 625       SymI_HasProto(hs_hpc_rootModule)                  \
 626       SymI_HasProto(hs_hpc_module)                      \
 627       SymI_HasProto(initLinker)                         \
 628       SymI_HasProto(unpackClosurezh_fast)               \
 629       SymI_HasProto(getApStackValzh_fast)               \
 630       SymI_HasProto(getSparkzh_fast)                    \
 631       SymI_HasProto(isCurrentThreadBoundzh_fast)        \
 632       SymI_HasProto(isDoubleDenormalized)               \
 633       SymI_HasProto(isDoubleInfinite)                   \
 634       SymI_HasProto(isDoubleNaN)                        \
 635       SymI_HasProto(isDoubleNegativeZero)               \
 636       SymI_HasProto(isEmptyMVarzh_fast)                 \
 637       SymI_HasProto(isFloatDenormalized)                \
 638       SymI_HasProto(isFloatInfinite)                    \
 639       SymI_HasProto(isFloatNaN)                         \
 640       SymI_HasProto(isFloatNegativeZero)                \
 641       SymI_HasProto(killThreadzh_fast)                  \
 642       SymI_HasProto(loadObj)                            \
 643       SymI_HasProto(insertStableSymbol)                 \
 644       SymI_HasProto(insertSymbol)                       \
 645       SymI_HasProto(lookupSymbol)                       \
 646       SymI_HasProto(makeStablePtrzh_fast)               \
 647       SymI_HasProto(mkApUpd0zh_fast)                    \
 648       SymI_HasProto(myThreadIdzh_fast)                  \
 649       SymI_HasProto(labelThreadzh_fast)                 \
 650       SymI_HasProto(newArrayzh_fast)                    \
 651       SymI_HasProto(newBCOzh_fast)                      \
 652       SymI_HasProto(newByteArrayzh_fast)                \
 653       SymI_HasProto_redirect(newCAF, newDynCAF)         \
 654       SymI_HasProto(newMVarzh_fast)                     \
 655       SymI_HasProto(newMutVarzh_fast)                   \
 656       SymI_HasProto(newTVarzh_fast)                     \
 657       SymI_HasProto(noDuplicatezh_fast)                 \
 658       SymI_HasProto(atomicModifyMutVarzh_fast)          \
 659       SymI_HasProto(newPinnedByteArrayzh_fast)          \
 660       SymI_HasProto(newAlignedPinnedByteArrayzh_fast)   \
 661       SymI_HasProto(newSpark)                           \
 662       SymI_HasProto(performGC)                          \
 663       SymI_HasProto(performMajorGC)                     \
 664       SymI_HasProto(prog_argc)                          \
 665       SymI_HasProto(prog_argv)                          \
 666       SymI_HasProto(putMVarzh_fast)                     \
 667       SymI_HasProto(raisezh_fast)                       \
 668       SymI_HasProto(raiseIOzh_fast)                     \
 669       SymI_HasProto(readTVarzh_fast)                    \
 670       SymI_HasProto(readTVarIOzh_fast)                  \
 671       SymI_HasProto(resetNonBlockingFd)                 \
 672       SymI_HasProto(resumeThread)                       \
 673       SymI_HasProto(resolveObjs)                        \
 674       SymI_HasProto(retryzh_fast)                       \
 675       SymI_HasProto(rts_apply)                          \
 676       SymI_HasProto(rts_checkSchedStatus)               \
 677       SymI_HasProto(rts_eval)                           \
 678       SymI_HasProto(rts_evalIO)                         \
 679       SymI_HasProto(rts_evalLazyIO)                     \
 680       SymI_HasProto(rts_evalStableIO)                   \
 681       SymI_HasProto(rts_eval_)                          \
 682       SymI_HasProto(rts_getBool)                        \
 683       SymI_HasProto(rts_getChar)                        \
 684       SymI_HasProto(rts_getDouble)                      \
 685       SymI_HasProto(rts_getFloat)                       \
 686       SymI_HasProto(rts_getInt)                         \
 687       SymI_HasProto(rts_getInt8)                        \
 688       SymI_HasProto(rts_getInt16)                       \
 689       SymI_HasProto(rts_getInt32)                       \
 690       SymI_HasProto(rts_getInt64)                       \
 691       SymI_HasProto(rts_getPtr)                         \
 692       SymI_HasProto(rts_getFunPtr)                      \
 693       SymI_HasProto(rts_getStablePtr)                   \
 694       SymI_HasProto(rts_getThreadId)                    \
 695       SymI_HasProto(rts_getWord)                        \
 696       SymI_HasProto(rts_getWord8)                       \
 697       SymI_HasProto(rts_getWord16)                      \
 698       SymI_HasProto(rts_getWord32)                      \
 699       SymI_HasProto(rts_getWord64)                      \
 700       SymI_HasProto(rts_lock)                           \
 701       SymI_HasProto(rts_mkBool)                         \
 702       SymI_HasProto(rts_mkChar)                         \
 703       SymI_HasProto(rts_mkDouble)                       \
 704       SymI_HasProto(rts_mkFloat)                        \
 705       SymI_HasProto(rts_mkInt)                          \
 706       SymI_HasProto(rts_mkInt8)                         \
 707       SymI_HasProto(rts_mkInt16)                        \
 708       SymI_HasProto(rts_mkInt32)                        \
 709       SymI_HasProto(rts_mkInt64)                        \
 710       SymI_HasProto(rts_mkPtr)                          \
 711       SymI_HasProto(rts_mkFunPtr)                       \
 712       SymI_HasProto(rts_mkStablePtr)                    \
 713       SymI_HasProto(rts_mkString)                       \
 714       SymI_HasProto(rts_mkWord)                         \
 715       SymI_HasProto(rts_mkWord8)                        \
 716       SymI_HasProto(rts_mkWord16)                       \
 717       SymI_HasProto(rts_mkWord32)                       \
 718       SymI_HasProto(rts_mkWord64)                       \
 719       SymI_HasProto(rts_unlock)                         \
 720       SymI_HasProto(rts_unsafeGetMyCapability)          \
 721       SymI_HasProto(rtsSupportsBoundThreads)            \
 722       SymI_HasProto(__hscore_get_saved_termios)         \
 723       SymI_HasProto(__hscore_set_saved_termios)         \
 724       SymI_HasProto(setProgArgv)                        \
 725       SymI_HasProto(startupHaskell)                     \
 726       SymI_HasProto(shutdownHaskell)                    \
 727       SymI_HasProto(shutdownHaskellAndExit)             \
 728       SymI_HasProto(stable_ptr_table)                   \
 729       SymI_HasProto(stackOverflow)                      \
 730       SymI_HasProto(stg_CAF_BLACKHOLE_info)             \
 731       SymI_HasProto(__stg_EAGER_BLACKHOLE_info)         \
 732       SymI_HasProto(awakenBlockedQueue)                 \
 733       SymI_HasProto(startTimer)                         \
 734       SymI_HasProto(stg_CHARLIKE_closure)               \
 735       SymI_HasProto(stg_MVAR_CLEAN_info)                \
 736       SymI_HasProto(stg_MVAR_DIRTY_info)                \
 737       SymI_HasProto(stg_IND_STATIC_info)                \
 738       SymI_HasProto(stg_INTLIKE_closure)                \
 739       SymI_HasProto(stg_ARR_WORDS_info)                 \
 740       SymI_HasProto(stg_MUT_ARR_PTRS_DIRTY_info)        \
 741       SymI_HasProto(stg_MUT_ARR_PTRS_FROZEN_info)       \
 742       SymI_HasProto(stg_MUT_ARR_PTRS_FROZEN0_info)      \
 743       SymI_HasProto(stg_WEAK_info)                      \
 744       SymI_HasProto(stg_ap_v_info)                      \
 745       SymI_HasProto(stg_ap_f_info)                      \
 746       SymI_HasProto(stg_ap_d_info)                      \
 747       SymI_HasProto(stg_ap_l_info)                      \
 748       SymI_HasProto(stg_ap_n_info)                      \
 749       SymI_HasProto(stg_ap_p_info)                      \
 750       SymI_HasProto(stg_ap_pv_info)                     \
 751       SymI_HasProto(stg_ap_pp_info)                     \
 752       SymI_HasProto(stg_ap_ppv_info)                    \
 753       SymI_HasProto(stg_ap_ppp_info)                    \
 754       SymI_HasProto(stg_ap_pppv_info)                   \
 755       SymI_HasProto(stg_ap_pppp_info)                   \
 756       SymI_HasProto(stg_ap_ppppp_info)                  \
 757       SymI_HasProto(stg_ap_pppppp_info)                 \
 758       SymI_HasProto(stg_ap_0_fast)                      \
 759       SymI_HasProto(stg_ap_v_fast)                      \
 760       SymI_HasProto(stg_ap_f_fast)                      \
 761       SymI_HasProto(stg_ap_d_fast)                      \
 762       SymI_HasProto(stg_ap_l_fast)                      \
 763       SymI_HasProto(stg_ap_n_fast)                      \
 764       SymI_HasProto(stg_ap_p_fast)                      \
 765       SymI_HasProto(stg_ap_pv_fast)                     \
 766       SymI_HasProto(stg_ap_pp_fast)                     \
 767       SymI_HasProto(stg_ap_ppv_fast)                    \
 768       SymI_HasProto(stg_ap_ppp_fast)                    \
 769       SymI_HasProto(stg_ap_pppv_fast)                   \
 770       SymI_HasProto(stg_ap_pppp_fast)                   \
 771       SymI_HasProto(stg_ap_ppppp_fast)                  \
 772       SymI_HasProto(stg_ap_pppppp_fast)                 \
 773       SymI_HasProto(stg_ap_1_upd_info)                  \
 774       SymI_HasProto(stg_ap_2_upd_info)                  \
 775       SymI_HasProto(stg_ap_3_upd_info)                  \
 776       SymI_HasProto(stg_ap_4_upd_info)                  \
 777       SymI_HasProto(stg_ap_5_upd_info)                  \
 778       SymI_HasProto(stg_ap_6_upd_info)                  \
 779       SymI_HasProto(stg_ap_7_upd_info)                  \
 780       SymI_HasProto(stg_exit)                           \
 781       SymI_HasProto(stg_sel_0_upd_info)                 \
 782       SymI_HasProto(stg_sel_10_upd_info)                \
 783       SymI_HasProto(stg_sel_11_upd_info)                \
 784       SymI_HasProto(stg_sel_12_upd_info)                \
 785       SymI_HasProto(stg_sel_13_upd_info)                \
 786       SymI_HasProto(stg_sel_14_upd_info)                \
 787       SymI_HasProto(stg_sel_15_upd_info)                \
 788       SymI_HasProto(stg_sel_1_upd_info)                 \
 789       SymI_HasProto(stg_sel_2_upd_info)                 \
 790       SymI_HasProto(stg_sel_3_upd_info)                 \
 791       SymI_HasProto(stg_sel_4_upd_info)                 \
 792       SymI_HasProto(stg_sel_5_upd_info)                 \
 793       SymI_HasProto(stg_sel_6_upd_info)                 \
 794       SymI_HasProto(stg_sel_7_upd_info)                 \
 795       SymI_HasProto(stg_sel_8_upd_info)                 \
 796       SymI_HasProto(stg_sel_9_upd_info)                 \
 797       SymI_HasProto(stg_upd_frame_info)                 \
 798       SymI_HasProto(suspendThread)                      \
 799       SymI_HasProto(takeMVarzh_fast)                    \
 800       SymI_HasProto(threadStatuszh_fast)                \
 801       SymI_HasProto(tryPutMVarzh_fast)                  \
 802       SymI_HasProto(tryTakeMVarzh_fast)                 \
 803       SymI_HasProto(unblockAsyncExceptionszh_fast)      \
 804       SymI_HasProto(unloadObj)                          \
 805       SymI_HasProto(unsafeThawArrayzh_fast)             \
 806       SymI_HasProto(waitReadzh_fast)                    \
 807       SymI_HasProto(waitWritezh_fast)                   \
 808       SymI_HasProto(writeTVarzh_fast)                   \
 809       SymI_HasProto(yieldzh_fast)                       \
 810       SymI_NeedsProto(stg_interp_constr_entry)          \
 811       SymI_HasProto(alloc_blocks)                       \
 812       SymI_HasProto(alloc_blocks_lim)                   \
 813       SymI_HasProto(allocateLocal)                      \
 814       SymI_HasProto(allocateExec)                       \
 815       SymI_HasProto(freeExec)                           \
 816       SymI_HasProto(getAllocations)                     \
 817       SymI_HasProto(revertCAFs)                         \
 818       SymI_HasProto(RtsFlags)                           \
 819       SymI_NeedsProto(rts_breakpoint_io_action)         \
 820       SymI_NeedsProto(rts_stop_next_breakpoint)         \
 821       SymI_NeedsProto(rts_stop_on_exception)            \
 822       SymI_HasProto(stopTimer)                          \
 823       SymI_HasProto(n_capabilities)                     \
 824       SymI_HasProto(traceCcszh_fast)                    \
 825       RTS_USER_SIGNALS_SYMBOLS
 826
 827
 828 // 64-bit support functions in libgcc.a
 829 #if defined(__GNUC__) && SIZEOF_VOID_P <= 4
 830 #define RTS_LIBGCC_SYMBOLS                             \
 831       SymI_NeedsProto(__divdi3)                        \
 832       SymI_NeedsProto(__udivdi3)                       \
 833       SymI_NeedsProto(__moddi3)                        \
 834       SymI_NeedsProto(__umoddi3)                       \
 835       SymI_NeedsProto(__muldi3)                        \
 836       SymI_NeedsProto(__ashldi3)                       \
 837       SymI_NeedsProto(__ashrdi3)                       \
 838       SymI_NeedsProto(__lshrdi3)                       \
 839       SymI_NeedsProto(__eprintf)
 840 #elif defined(ia64_HOST_ARCH)
 841 #define RTS_LIBGCC_SYMBOLS                              \
 842       SymI_NeedsProto(__divdi3)                         \
 843       SymI_NeedsProto(__udivdi3)                        \
 844       SymI_NeedsProto(__moddi3)                         \
 845       SymI_NeedsProto(__umoddi3)                        \
 846       SymI_NeedsProto(__divsf3)                         \
 847       SymI_NeedsProto(__divdf3)
 848 #else
 849 #define RTS_LIBGCC_SYMBOLS
 850 #endif
 851
 852 #if defined(darwin_HOST_OS) && defined(powerpc_HOST_ARCH)
 853       // Symbols that don't have a leading underscore
 854       // on Mac OS X. They have to receive special treatment,
 855       // see machoInitSymbolsWithoutUnderscore()
 856 #define RTS_MACHO_NOUNDERLINE_SYMBOLS           \
 857       SymI_NeedsProto(saveFP)                           \
 858       SymI_NeedsProto(restFP)
 859 #endif
 860
 861 /* entirely bogus claims about types of these symbols */
 862 #define SymI_NeedsProto(vvv)  extern void vvv(void);
 863 #if defined(__PIC__) && defined(mingw32_TARGET_OS)
 864 #define SymE_HasProto(vvv)    SymE_HasProto(vvv);
 865 #define SymE_NeedsProto(vvv)    extern void _imp__ ## vvv (void);
 866 #else
 867 #define SymE_NeedsProto(vvv)  SymI_NeedsProto(vvv);
 868 #define SymE_HasProto(vvv)    SymI_HasProto(vvv)
 869 #endif
 870 #define SymI_HasProto(vvv) /**/
 871 #define SymI_HasProto_redirect(vvv,xxx) /**/
 872 RTS_SYMBOLS
 873 RTS_RET_SYMBOLS
 874 RTS_POSIX_ONLY_SYMBOLS
 875 RTS_MINGW_ONLY_SYMBOLS
 876 RTS_CYGWIN_ONLY_SYMBOLS
 877 RTS_DARWIN_ONLY_SYMBOLS
 878 RTS_LIBGCC_SYMBOLS
 879 RTS_LIBFFI_SYMBOLS
 880 #undef SymI_NeedsProto
 881 #undef SymI_HasProto
 882 #undef SymI_HasProto_redirect
 883 #undef SymE_HasProto
 884 #undef SymE_NeedsProto
 885
 886 #ifdef LEADING_UNDERSCORE
 887 #define MAYBE_LEADING_UNDERSCORE_STR(s) ("_" s)
 888 #else
 889 #define MAYBE_LEADING_UNDERSCORE_STR(s) (s)
 890 #endif
 891
 892 #define SymI_HasProto(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
 893                     (void*)(&(vvv)) },
 894 #define SymE_HasProto(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
 895             (void*)DLL_IMPORT_DATA_REF(vvv) },
 896
 897 #define SymI_NeedsProto(vvv) SymI_HasProto(vvv)
 898 #define SymE_NeedsProto(vvv) SymE_HasProto(vvv)
 899
 900 // SymI_HasProto_redirect allows us to redirect references to one symbol to
 901 // another symbol.  See newCAF/newDynCAF for an example.
 902 #define SymI_HasProto_redirect(vvv,xxx) \
 903     { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
 904       (void*)(&(xxx)) },
 905
 906 static RtsSymbolVal rtsSyms[] = {
 907       RTS_SYMBOLS
 908       RTS_RET_SYMBOLS
 909       RTS_POSIX_ONLY_SYMBOLS
 910       RTS_MINGW_ONLY_SYMBOLS
 911       RTS_CYGWIN_ONLY_SYMBOLS
 912       RTS_DARWIN_ONLY_SYMBOLS
 913       RTS_LIBGCC_SYMBOLS
 914       RTS_LIBFFI_SYMBOLS
 915 #if defined(darwin_HOST_OS) && defined(i386_HOST_ARCH)
 916       // dyld stub code contains references to this,
 917       // but it should never be called because we treat
 918       // lazy pointers as nonlazy.
 919       { "dyld_stub_binding_helper", (void*)0xDEADBEEF },
 920 #endif
 921       { 0, 0 } /* sentinel */
 922 };
 923
 924
 925
 926 /* -----------------------------------------------------------------------------
 927  * Insert symbols into hash tables, checking for duplicates.
 928  */
 929
 930 static void ghciInsertStrHashTable ( char* obj_name,
 931                                      HashTable *table,
 932                                      char* key,
 933                                      void *data
 934                                    )
 935 {
 936    if (lookupHashTable(table, (StgWord)key) == NULL)
 937    {
 938       insertStrHashTable(table, (StgWord)key, data);
 939       return;
 940    }
 941    debugBelch(
 942       "\n\n"
 943       "GHCi runtime linker: fatal error: I found a duplicate definition for symbol\n"
 944       "   %s\n"
 945       "whilst processing object file\n"
 946       "   %s\n"
 947       "This could be caused by:\n"
 948       "   * Loading two different object files which export the same symbol\n"
 949       "   * Specifying the same object file twice on the GHCi command line\n"
 950       "   * An incorrect `package.conf' entry, causing some object to be\n"
 951       "     loaded twice.\n"
 952       "GHCi cannot safely continue in this situation.  Exiting now.  Sorry.\n"
 953       "\n",
 954       (char*)key,
 955       obj_name
 956    );
 957    exit(1);
 958 }
 959 /* -----------------------------------------------------------------------------
 960  * initialize the object linker
 961  */
 962
 963
 964 static int linker_init_done = 0 ;
 965
 966 #if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
 967 static void *dl_prog_handle;
 968 #endif
 969
 970 void
 971 initLinker( void )
 972 {
 973     RtsSymbolVal *sym;
 974
 975     /* Make initLinker idempotent, so we can call it
 976        before evey relevant operation; that means we
 977        don't need to initialise the linker separately */
 978     if (linker_init_done == 1) { return; } else {
 979       linker_init_done = 1;
 980     }
 981
 982     stablehash = allocStrHashTable();
 983     symhash = allocStrHashTable();
 984
 985     /* populate the symbol table with stuff from the RTS */
 986     for (sym = rtsSyms; sym->lbl != NULL; sym++) {
 987         ghciInsertStrHashTable("(GHCi built-in symbols)",
 988                                symhash, sym->lbl, sym->addr);
 989     }
 990 #   if defined(OBJFORMAT_MACHO) && defined(powerpc_HOST_ARCH)
 991     machoInitSymbolsWithoutUnderscore();
 992 #   endif
 993
 994 #   if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
 995 #   if defined(RTLD_DEFAULT)
 996     dl_prog_handle = RTLD_DEFAULT;
 997 #   else
 998     dl_prog_handle = dlopen(NULL, RTLD_LAZY);
 999 #   endif /* RTLD_DEFAULT */
1000 #   endif
1001
1002 #if defined(x86_64_HOST_ARCH)
1003     if (RtsFlags.MiscFlags.linkerMemBase != 0) {
1004         // User-override for mmap_32bit_base
1005         mmap_32bit_base = (void*)RtsFlags.MiscFlags.linkerMemBase;
1006     }
1007 #endif
1008
1009 #if defined(mingw32_HOST_OS)
1010     /*
1011      * These two libraries cause problems when added to the static link,
1012      * but are necessary for resolving symbols in GHCi, hence we load
1013      * them manually here.
1014      */
1015     addDLL("msvcrt");
1016     addDLL("kernel32");
1017 #endif
1018 }
1019
1020 /* -----------------------------------------------------------------------------
1021  *                  Loading DLL or .so dynamic libraries
1022  * -----------------------------------------------------------------------------
1023  *
1024  * Add a DLL from which symbols may be found.  In the ELF case, just
1025  * do RTLD_GLOBAL-style add, so no further messing around needs to
1026  * happen in order that symbols in the loaded .so are findable --
1027  * lookupSymbol() will subsequently see them by dlsym on the program's
1028  * dl-handle.  Returns NULL if success, otherwise ptr to an err msg.
1029  *
1030  * In the PEi386 case, open the DLLs and put handles to them in a
1031  * linked list.  When looking for a symbol, try all handles in the
1032  * list.  This means that we need to load even DLLs that are guaranteed
1033  * to be in the ghc.exe image already, just so we can get a handle
1034  * to give to loadSymbol, so that we can find the symbols.  For such
1035  * libraries, the LoadLibrary call should be a no-op except for returning
1036  * the handle.
1037  *
1038  */
1039
1040 #if defined(OBJFORMAT_PEi386)
1041 /* A record for storing handles into DLLs. */
1042
1043 typedef
1044    struct _OpenedDLL {
1045       char*              name;
1046       struct _OpenedDLL* next;
1047       HINSTANCE instance;
1048    }
1049    OpenedDLL;
1050
1051 /* A list thereof. */
1052 static OpenedDLL* opened_dlls = NULL;
1053 #endif
1054
1055 const char *
1056 addDLL( char *dll_name )
1057 {
1058 #  if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1059    /* ------------------- ELF DLL loader ------------------- */
1060    void *hdl;
1061    const char *errmsg;
1062
1063    initLinker();
1064
1065    // omitted: RTLD_NOW
1066    // see http://www.haskell.org/pipermail/cvs-ghc/2007-September/038570.html
1067    hdl= dlopen(dll_name, RTLD_LAZY | RTLD_GLOBAL);
1068
1069    if (hdl == NULL) {
1070       /* dlopen failed; return a ptr to the error msg. */
1071       errmsg = dlerror();
1072       if (errmsg == NULL) errmsg = "addDLL: unknown error";
1073       return errmsg;
1074    } else {
1075       return NULL;
1076    }
1077    /*NOTREACHED*/
1078
1079 #  elif defined(OBJFORMAT_PEi386)
1080    /* ------------------- Win32 DLL loader ------------------- */
1081
1082    char*      buf;
1083    OpenedDLL* o_dll;
1084    HINSTANCE  instance;
1085
1086    initLinker();
1087
1088    /* debugBelch("\naddDLL; dll_name = `%s'\n", dll_name); */
1089
1090    /* See if we've already got it, and ignore if so. */
1091    for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
1092       if (0 == strcmp(o_dll->name, dll_name))
1093          return NULL;
1094    }
1095
1096    /* The file name has no suffix (yet) so that we can try
1097       both foo.dll and foo.drv
1098
1099       The documentation for LoadLibrary says:
1100         If no file name extension is specified in the lpFileName
1101         parameter, the default library extension .dll is
1102         appended. However, the file name string can include a trailing
1103         point character (.) to indicate that the module name has no
1104         extension. */
1105
1106    buf = stgMallocBytes(strlen(dll_name) + 10, "addDLL");
1107    sprintf(buf, "%s.DLL", dll_name);
1108    instance = LoadLibrary(buf);
1109    if (instance == NULL) {
1110        if (GetLastError() != ERROR_MOD_NOT_FOUND) goto error;
1111        // KAA: allow loading of drivers (like winspool.drv)
1112        sprintf(buf, "%s.DRV", dll_name);
1113        instance = LoadLibrary(buf);
1114        if (instance == NULL) {
1115            if (GetLastError() != ERROR_MOD_NOT_FOUND) goto error;
1116            // #1883: allow loading of unix-style libfoo.dll DLLs
1117            sprintf(buf, "lib%s.DLL", dll_name);
1118            instance = LoadLibrary(buf);
1119            if (instance == NULL) {
1120                goto error;
1121            }
1122        }
1123    }
1124    stgFree(buf);
1125
1126    /* Add this DLL to the list of DLLs in which to search for symbols. */
1127    o_dll = stgMallocBytes( sizeof(OpenedDLL), "addDLL" );
1128    o_dll->name     = stgMallocBytes(1+strlen(dll_name), "addDLL");
1129    strcpy(o_dll->name, dll_name);
1130    o_dll->instance = instance;
1131    o_dll->next     = opened_dlls;
1132    opened_dlls     = o_dll;
1133
1134    return NULL;
1135
1136 error:
1137    stgFree(buf);
1138    sysErrorBelch(dll_name);
1139
1140    /* LoadLibrary failed; return a ptr to the error msg. */
1141    return "addDLL: could not load DLL";
1142
1143 #  else
1144    barf("addDLL: not implemented on this platform");
1145 #  endif
1146 }
1147
1148 /* -----------------------------------------------------------------------------
1149  * insert a stable symbol in the hash table
1150  */
1151
1152 void
1153 insertStableSymbol(char* obj_name, char* key, StgPtr p)
1154 {
1155   ghciInsertStrHashTable(obj_name, stablehash, key, getStablePtr(p));
1156 }
1157
1158
1159 /* -----------------------------------------------------------------------------
1160  * insert a symbol in the hash table
1161  */
1162 void
1163 insertSymbol(char* obj_name, char* key, void* data)
1164 {
1165   ghciInsertStrHashTable(obj_name, symhash, key, data);
1166 }
1167
1168 /* -----------------------------------------------------------------------------
1169  * lookup a symbol in the hash table
1170  */
1171 void *
1172 lookupSymbol( char *lbl )
1173 {
1174     void *val;
1175     initLinker() ;
1176     ASSERT(symhash != NULL);
1177     val = lookupStrHashTable(symhash, lbl);
1178
1179     if (val == NULL) {
1180 #       if defined(OBJFORMAT_ELF)
1181         return dlsym(dl_prog_handle, lbl);
1182 #       elif defined(OBJFORMAT_MACHO)
1183 #       if HAVE_DLFCN_H
1184         /* On OS X 10.3 and later, we use dlsym instead of the old legacy
1185            interface.
1186
1187            HACK: On OS X, global symbols are prefixed with an underscore.
1188                  However, dlsym wants us to omit the leading underscore from the
1189                  symbol name. For now, we simply strip it off here (and ONLY
1190                  here).
1191         */
1192         ASSERT(lbl[0] == '_');
1193         return dlsym(dl_prog_handle, lbl+1);
1194 #       else
1195         if(NSIsSymbolNameDefined(lbl)) {
1196             NSSymbol symbol = NSLookupAndBindSymbol(lbl);
1197             return NSAddressOfSymbol(symbol);
1198         } else {
1199             return NULL;
1200         }
1201 #       endif /* HAVE_DLFCN_H */
1202 #       elif defined(OBJFORMAT_PEi386)
1203         void* sym;
1204
1205         sym = lookupSymbolInDLLs(lbl);
1206         if (sym != NULL) { return sym; };
1207
1208         // Also try looking up the symbol without the @N suffix.  Some
1209         // DLLs have the suffixes on their symbols, some don't.
1210         zapTrailingAtSign ( lbl );
1211         sym = lookupSymbolInDLLs(lbl);
1212         if (sym != NULL) { return sym; };
1213         return NULL;
1214
1215 #       else
1216         ASSERT(2+2 == 5);
1217         return NULL;
1218 #       endif
1219     } else {
1220         return val;
1221     }
1222 }
1223
1224 /* -----------------------------------------------------------------------------
1225  * Debugging aid: look in GHCi's object symbol tables for symbols
1226  * within DELTA bytes of the specified address, and show their names.
1227  */
1228 #ifdef DEBUG
1229 void ghci_enquire ( char* addr );
1230
1231 void ghci_enquire ( char* addr )
1232 {
1233    int   i;
1234    char* sym;
1235    char* a;
1236    const int DELTA = 64;
1237    ObjectCode* oc;
1238
1239    initLinker();
1240
1241    for (oc = objects; oc; oc = oc->next) {
1242       for (i = 0; i < oc->n_symbols; i++) {
1243          sym = oc->symbols[i];
1244          if (sym == NULL) continue;
1245          a = NULL;
1246          if (a == NULL) {
1247             a = lookupStrHashTable(symhash, sym);
1248          }
1249          if (a == NULL) {
1250              // debugBelch("ghci_enquire: can't find %s\n", sym);
1251          }
1252          else if (addr-DELTA <= a && a <= addr+DELTA) {
1253             debugBelch("%p + %3d  ==  `%s'\n", addr, (int)(a - addr), sym);
1254          }
1255       }
1256    }
1257 }
1258 #endif
1259
1260 #ifdef ia64_HOST_ARCH
1261 static unsigned int PLTSize(void);
1262 #endif
1263
1264 #ifdef USE_MMAP
1265 #define ROUND_UP(x,size) ((x + size - 1) & ~(size - 1))
1266
1267 static void *
1268 mmapForLinker (size_t bytes, nat flags, int fd)
1269 {
1270    void *map_addr = NULL;
1271    void *result;
1272    int pagesize, size;
1273    static nat fixed = 0;
1274
1275    pagesize = getpagesize();
1276    size = ROUND_UP(bytes, pagesize);
1277
1278 #if defined(x86_64_HOST_ARCH)
1279 mmap_again:
1280
1281    if (mmap_32bit_base != 0) {
1282        map_addr = mmap_32bit_base;
1283    }
1284 #endif
1285
1286    result = mmap(map_addr, size, PROT_EXEC|PROT_READ|PROT_WRITE,
1287                     MAP_PRIVATE|TRY_MAP_32BIT|fixed|flags, fd, 0);
1288
1289    if (result == MAP_FAILED) {
1290        sysErrorBelch("mmap %lu bytes at %p",(lnat)size,map_addr);
1291        errorBelch("Try specifying an address with +RTS -xm<addr> -RTS");
1292        stg_exit(EXIT_FAILURE);
1293    }
1294
1295 #if defined(x86_64_HOST_ARCH)
1296    if (mmap_32bit_base != 0) {
1297        if (result == map_addr) {
1298            mmap_32bit_base = map_addr + size;
1299        } else {
1300            if ((W_)result > 0x80000000) {
1301                // oops, we were given memory over 2Gb
1302 #if defined(freebsd_HOST_OS)
1303                // Some platforms require MAP_FIXED.  This is normally
1304                // a bad idea, because MAP_FIXED will overwrite
1305                // existing mappings.
1306                munmap(result,size);
1307                fixed = MAP_FIXED;
1308                goto mmap_again;
1309 #else
1310                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);
1311 #endif
1312            } else {
1313                // hmm, we were given memory somewhere else, but it's
1314                // still under 2Gb so we can use it.  Next time, ask
1315                // for memory right after the place we just got some
1316                mmap_32bit_base = (void*)result + size;
1317            }
1318        }
1319    } else {
1320        if ((W_)result > 0x80000000) {
1321            // oops, we were given memory over 2Gb
1322            // ... try allocating memory somewhere else?;
1323            debugTrace(DEBUG_linker,"MAP_32BIT didn't work; gave us %lu bytes at 0x%p", bytes, result);
1324            munmap(result, size);
1325
1326            // Set a base address and try again... (guess: 1Gb)
1327            mmap_32bit_base = (void*)0x40000000;
1328            goto mmap_again;
1329        }
1330    }
1331 #endif
1332
1333    return result;
1334 }
1335 #endif // USE_MMAP
1336
1337 /* -----------------------------------------------------------------------------
1338  * Load an obj (populate the global symbol table, but don't resolve yet)
1339  *
1340  * Returns: 1 if ok, 0 on error.
1341  */
1342 HsInt
1343 loadObj( char *path )
1344 {
1345    ObjectCode* oc;
1346    struct stat st;
1347    int r;
1348 #ifdef USE_MMAP
1349    int fd;
1350 #else
1351    FILE *f;
1352 #endif
1353    initLinker();
1354
1355    /* debugBelch("loadObj %s\n", path ); */
1356
1357    /* Check that we haven't already loaded this object.
1358       Ignore requests to load multiple times */
1359    {
1360        ObjectCode *o;
1361        int is_dup = 0;
1362        for (o = objects; o; o = o->next) {
1363           if (0 == strcmp(o->fileName, path)) {
1364              is_dup = 1;
1365              break; /* don't need to search further */
1366           }
1367        }
1368        if (is_dup) {
1369           IF_DEBUG(linker, debugBelch(
1370             "GHCi runtime linker: warning: looks like you're trying to load the\n"
1371             "same object file twice:\n"
1372             "   %s\n"
1373             "GHCi will ignore this, but be warned.\n"
1374             , path));
1375           return 1; /* success */
1376        }
1377    }
1378
1379    oc = stgMallocBytes(sizeof(ObjectCode), "loadObj(oc)");
1380
1381 #  if defined(OBJFORMAT_ELF)
1382    oc->formatName = "ELF";
1383 #  elif defined(OBJFORMAT_PEi386)
1384    oc->formatName = "PEi386";
1385 #  elif defined(OBJFORMAT_MACHO)
1386    oc->formatName = "Mach-O";
1387 #  else
1388    stgFree(oc);
1389    barf("loadObj: not implemented on this platform");
1390 #  endif
1391
1392    r = stat(path, &st);
1393    if (r == -1) { return 0; }
1394
1395    /* sigh, strdup() isn't a POSIX function, so do it the long way */
1396    oc->fileName = stgMallocBytes( strlen(path)+1, "loadObj" );
1397    strcpy(oc->fileName, path);
1398
1399    oc->fileSize          = st.st_size;
1400    oc->symbols           = NULL;
1401    oc->sections          = NULL;
1402    oc->proddables        = NULL;
1403
1404    /* chain it onto the list of objects */
1405    oc->next              = objects;
1406    objects               = oc;
1407
1408 #ifdef USE_MMAP
1409    /* On many architectures malloc'd memory isn't executable, so we need to use mmap. */
1410
1411 #if defined(openbsd_HOST_OS)
1412    fd = open(path, O_RDONLY, S_IRUSR);
1413 #else
1414    fd = open(path, O_RDONLY);
1415 #endif
1416    if (fd == -1)
1417       barf("loadObj: can't open `%s'", path);
1418
1419 #ifdef ia64_HOST_ARCH
1420    /* The PLT needs to be right before the object */
1421    {
1422    int pagesize, n;
1423    pagesize = getpagesize();
1424    n = ROUND_UP(PLTSize(), pagesize);
1425    oc->plt = mmap(NULL, n, PROT_EXEC|PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
1426    if (oc->plt == MAP_FAILED)
1427       barf("loadObj: can't allocate PLT");
1428
1429    oc->pltIndex = 0;
1430    map_addr = oc->plt + n;
1431
1432    n = ROUND_UP(oc->fileSize, pagesize);
1433    oc->image = mmap(map_addr, n, PROT_EXEC|PROT_READ|PROT_WRITE,
1434                     MAP_PRIVATE|TRY_MAP_32BIT, fd, 0);
1435    if (oc->image == MAP_FAILED)
1436       barf("loadObj: can't map `%s'", path);
1437    }
1438 #else
1439    oc->image = mmapForLinker(oc->fileSize, 0, fd);
1440 #endif
1441
1442    close(fd);
1443
1444 #else /* !USE_MMAP */
1445    /* load the image into memory */
1446    f = fopen(path, "rb");
1447    if (!f)
1448        barf("loadObj: can't read `%s'", path);
1449
1450 #   if defined(mingw32_HOST_OS)
1451         // TODO: We would like to use allocateExec here, but allocateExec
1452         //       cannot currently allocate blocks large enough.
1453     oc->image = VirtualAlloc(NULL, oc->fileSize, MEM_RESERVE | MEM_COMMIT,
1454                              PAGE_EXECUTE_READWRITE);
1455 #   elif defined(darwin_HOST_OS)
1456     // In a Mach-O .o file, all sections can and will be misaligned
1457     // if the total size of the headers is not a multiple of the
1458     // desired alignment. This is fine for .o files that only serve
1459     // as input for the static linker, but it's not fine for us,
1460     // as SSE (used by gcc for floating point) and Altivec require
1461     // 16-byte alignment.
1462     // We calculate the correct alignment from the header before
1463     // reading the file, and then we misalign oc->image on purpose so
1464     // that the actual sections end up aligned again.
1465    oc->misalignment = machoGetMisalignment(f);
1466    oc->image = stgMallocBytes(oc->fileSize + oc->misalignment, "loadObj(image)");
1467    oc->image += oc->misalignment;
1468 #  else
1469    oc->image = stgMallocBytes(oc->fileSize, "loadObj(image)");
1470 #  endif
1471
1472    {
1473        int n;
1474        n = fread ( oc->image, 1, oc->fileSize, f );
1475        if (n != oc->fileSize)
1476            barf("loadObj: error whilst reading `%s'", path);
1477    }
1478    fclose(f);
1479 #endif /* USE_MMAP */
1480
1481 #  if defined(OBJFORMAT_MACHO) && (defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH))
1482    r = ocAllocateSymbolExtras_MachO ( oc );
1483    if (!r) { return r; }
1484 #  elif defined(OBJFORMAT_ELF) && (defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH))
1485    r = ocAllocateSymbolExtras_ELF ( oc );
1486    if (!r) { return r; }
1487 #endif
1488
1489    /* verify the in-memory image */
1490 #  if defined(OBJFORMAT_ELF)
1491    r = ocVerifyImage_ELF ( oc );
1492 #  elif defined(OBJFORMAT_PEi386)
1493    r = ocVerifyImage_PEi386 ( oc );
1494 #  elif defined(OBJFORMAT_MACHO)
1495    r = ocVerifyImage_MachO ( oc );
1496 #  else
1497    barf("loadObj: no verify method");
1498 #  endif
1499    if (!r) { return r; }
1500
1501    /* build the symbol list for this image */
1502 #  if defined(OBJFORMAT_ELF)
1503    r = ocGetNames_ELF ( oc );
1504 #  elif defined(OBJFORMAT_PEi386)
1505    r = ocGetNames_PEi386 ( oc );
1506 #  elif defined(OBJFORMAT_MACHO)
1507    r = ocGetNames_MachO ( oc );
1508 #  else
1509    barf("loadObj: no getNames method");
1510 #  endif
1511    if (!r) { return r; }
1512
1513    /* loaded, but not resolved yet */
1514    oc->status = OBJECT_LOADED;
1515
1516    return 1;
1517 }
1518
1519 /* -----------------------------------------------------------------------------
1520  * resolve all the currently unlinked objects in memory
1521  *
1522  * Returns: 1 if ok, 0 on error.
1523  */
1524 HsInt
1525 resolveObjs( void )
1526 {
1527     ObjectCode *oc;
1528     int r;
1529
1530     initLinker();
1531
1532     for (oc = objects; oc; oc = oc->next) {
1533         if (oc->status != OBJECT_RESOLVED) {
1534 #           if defined(OBJFORMAT_ELF)
1535             r = ocResolve_ELF ( oc );
1536 #           elif defined(OBJFORMAT_PEi386)
1537             r = ocResolve_PEi386 ( oc );
1538 #           elif defined(OBJFORMAT_MACHO)
1539             r = ocResolve_MachO ( oc );
1540 #           else
1541             barf("resolveObjs: not implemented on this platform");
1542 #           endif
1543             if (!r) { return r; }
1544             oc->status = OBJECT_RESOLVED;
1545         }
1546     }
1547     return 1;
1548 }
1549
1550 /* -----------------------------------------------------------------------------
1551  * delete an object from the pool
1552  */
1553 HsInt
1554 unloadObj( char *path )
1555 {
1556     ObjectCode *oc, *prev;
1557
1558     ASSERT(symhash != NULL);
1559     ASSERT(objects != NULL);
1560
1561     initLinker();
1562
1563     prev = NULL;
1564     for (oc = objects; oc; prev = oc, oc = oc->next) {
1565         if (!strcmp(oc->fileName,path)) {
1566
1567             /* Remove all the mappings for the symbols within this
1568              * object..
1569              */
1570             {
1571                 int i;
1572                 for (i = 0; i < oc->n_symbols; i++) {
1573                    if (oc->symbols[i] != NULL) {
1574                        removeStrHashTable(symhash, oc->symbols[i], NULL);
1575                    }
1576                 }
1577             }
1578
1579             if (prev == NULL) {
1580                 objects = oc->next;
1581             } else {
1582                 prev->next = oc->next;
1583             }
1584
1585             // We're going to leave this in place, in case there are
1586             // any pointers from the heap into it:
1587                 // #ifdef mingw32_HOST_OS
1588                 //  VirtualFree(oc->image);
1589                 // #else
1590             //  stgFree(oc->image);
1591             // #endif
1592             stgFree(oc->fileName);
1593             stgFree(oc->symbols);
1594             stgFree(oc->sections);
1595             stgFree(oc);
1596             return 1;
1597         }
1598     }
1599
1600     errorBelch("unloadObj: can't find `%s' to unload", path);
1601     return 0;
1602 }
1603
1604 /* -----------------------------------------------------------------------------
1605  * Sanity checking.  For each ObjectCode, maintain a list of address ranges
1606  * which may be prodded during relocation, and abort if we try and write
1607  * outside any of these.
1608  */
1609 static void addProddableBlock ( ObjectCode* oc, void* start, int size )
1610 {
1611    ProddableBlock* pb
1612       = stgMallocBytes(sizeof(ProddableBlock), "addProddableBlock");
1613    /* debugBelch("aPB %p %p %d\n", oc, start, size); */
1614    ASSERT(size > 0);
1615    pb->start      = start;
1616    pb->size       = size;
1617    pb->next       = oc->proddables;
1618    oc->proddables = pb;
1619 }
1620
1621 static void checkProddableBlock ( ObjectCode* oc, void* addr )
1622 {
1623    ProddableBlock* pb;
1624    for (pb = oc->proddables; pb != NULL; pb = pb->next) {
1625       char* s = (char*)(pb->start);
1626       char* e = s + pb->size - 1;
1627       char* a = (char*)addr;
1628       /* Assumes that the biggest fixup involves a 4-byte write.  This
1629          probably needs to be changed to 8 (ie, +7) on 64-bit
1630          plats. */
1631       if (a >= s && (a+3) <= e) return;
1632    }
1633    barf("checkProddableBlock: invalid fixup in runtime linker");
1634 }
1635
1636 /* -----------------------------------------------------------------------------
1637  * Section management.
1638  */
1639 static void addSection ( ObjectCode* oc, SectionKind kind,
1640                          void* start, void* end )
1641 {
1642    Section* s   = stgMallocBytes(sizeof(Section), "addSection");
1643    s->start     = start;
1644    s->end       = end;
1645    s->kind      = kind;
1646    s->next      = oc->sections;
1647    oc->sections = s;
1648    /*
1649    debugBelch("addSection: %p-%p (size %d), kind %d\n",
1650                    start, ((char*)end)-1, end - start + 1, kind );
1651    */
1652 }
1653
1654
1655 /* --------------------------------------------------------------------------
1656  * Symbol Extras.
1657  * This is about allocating a small chunk of memory for every symbol in the
1658  * object file. We make sure that the SymboLExtras are always "in range" of
1659  * limited-range PC-relative instructions on various platforms by allocating
1660  * them right next to the object code itself.
1661  */
1662
1663 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
1664
1665 /*
1666   ocAllocateSymbolExtras
1667
1668   Allocate additional space at the end of the object file image to make room
1669   for jump islands (powerpc, x86_64) and GOT entries (x86_64).
1670
1671   PowerPC relative branch instructions have a 24 bit displacement field.
1672   As PPC code is always 4-byte-aligned, this yields a +-32MB range.
1673   If a particular imported symbol is outside this range, we have to redirect
1674   the jump to a short piece of new code that just loads the 32bit absolute
1675   address and jumps there.
1676   On x86_64, PC-relative jumps and PC-relative accesses to the GOT are limited
1677   to 32 bits (+-2GB).
1678
1679   This function just allocates space for one SymbolExtra for every
1680   undefined symbol in the object file. The code for the jump islands is
1681   filled in by makeSymbolExtra below.
1682 */
1683
1684 static int ocAllocateSymbolExtras( ObjectCode* oc, int count, int first )
1685 {
1686 #ifdef USE_MMAP
1687   int pagesize, n, m;
1688 #endif
1689   int aligned;
1690 #ifndef USE_MMAP
1691   int misalignment = 0;
1692 #ifdef darwin_HOST_OS
1693   misalignment = oc->misalignment;
1694 #endif
1695 #endif
1696
1697   if( count > 0 )
1698   {
1699     // round up to the nearest 4
1700     aligned = (oc->fileSize + 3) & ~3;
1701
1702 #ifdef USE_MMAP
1703     pagesize = getpagesize();
1704     n = ROUND_UP( oc->fileSize, pagesize );
1705     m = ROUND_UP( aligned + sizeof (SymbolExtra) * count, pagesize );
1706
1707     /* we try to use spare space at the end of the last page of the
1708      * image for the jump islands, but if there isn't enough space
1709      * then we have to map some (anonymously, remembering MAP_32BIT).
1710      */
1711     if( m > n ) // we need to allocate more pages
1712     {
1713         oc->symbol_extras = mmapForLinker(sizeof(SymbolExtra) * count,
1714                                           MAP_ANONYMOUS, -1);
1715     }
1716     else
1717     {
1718         oc->symbol_extras = (SymbolExtra *) (oc->image + aligned);
1719     }
1720 #else
1721     oc->image -= misalignment;
1722     oc->image = stgReallocBytes( oc->image,
1723                                  misalignment +
1724                                  aligned + sizeof (SymbolExtra) * count,
1725                                  "ocAllocateSymbolExtras" );
1726     oc->image += misalignment;
1727
1728     oc->symbol_extras = (SymbolExtra *) (oc->image + aligned);
1729 #endif /* USE_MMAP */
1730
1731     memset( oc->symbol_extras, 0, sizeof (SymbolExtra) * count );
1732   }
1733   else
1734     oc->symbol_extras = NULL;
1735
1736   oc->first_symbol_extra = first;
1737   oc->n_symbol_extras = count;
1738
1739   return 1;
1740 }
1741
1742 static SymbolExtra* makeSymbolExtra( ObjectCode* oc,
1743                                      unsigned long symbolNumber,
1744                                      unsigned long target )
1745 {
1746   SymbolExtra *extra;
1747
1748   ASSERT( symbolNumber >= oc->first_symbol_extra
1749         && symbolNumber - oc->first_symbol_extra < oc->n_symbol_extras);
1750
1751   extra = &oc->symbol_extras[symbolNumber - oc->first_symbol_extra];
1752
1753 #ifdef powerpc_HOST_ARCH
1754   // lis r12, hi16(target)
1755   extra->jumpIsland.lis_r12     = 0x3d80;
1756   extra->jumpIsland.hi_addr     = target >> 16;
1757
1758   // ori r12, r12, lo16(target)
1759   extra->jumpIsland.ori_r12_r12 = 0x618c;
1760   extra->jumpIsland.lo_addr     = target & 0xffff;
1761
1762   // mtctr r12
1763   extra->jumpIsland.mtctr_r12   = 0x7d8903a6;
1764
1765   // bctr
1766   extra->jumpIsland.bctr        = 0x4e800420;
1767 #endif
1768 #ifdef x86_64_HOST_ARCH
1769         // jmp *-14(%rip)
1770   static uint8_t jmp[] = { 0xFF, 0x25, 0xF2, 0xFF, 0xFF, 0xFF };
1771   extra->addr = target;
1772   memcpy(extra->jumpIsland, jmp, 6);
1773 #endif
1774
1775   return extra;
1776 }
1777
1778 #endif
1779
1780 /* --------------------------------------------------------------------------
1781  * PowerPC specifics (instruction cache flushing)
1782  * ------------------------------------------------------------------------*/
1783
1784 #ifdef powerpc_TARGET_ARCH
1785 /*
1786    ocFlushInstructionCache
1787
1788    Flush the data & instruction caches.
1789    Because the PPC has split data/instruction caches, we have to
1790    do that whenever we modify code at runtime.
1791  */
1792
1793 static void ocFlushInstructionCache( ObjectCode *oc )
1794 {
1795     int n = (oc->fileSize + sizeof( SymbolExtra ) * oc->n_symbol_extras + 3) / 4;
1796     unsigned long *p = (unsigned long *) oc->image;
1797
1798     while( n-- )
1799     {
1800         __asm__ volatile ( "dcbf 0,%0\n\t"
1801                            "sync\n\t"
1802                            "icbi 0,%0"
1803                            :
1804                            : "r" (p)
1805                          );
1806         p++;
1807     }
1808     __asm__ volatile ( "sync\n\t"
1809                        "isync"
1810                      );
1811 }
1812 #endif
1813
1814 /* --------------------------------------------------------------------------
1815  * PEi386 specifics (Win32 targets)
1816  * ------------------------------------------------------------------------*/
1817
1818 /* The information for this linker comes from
1819       Microsoft Portable Executable
1820       and Common Object File Format Specification
1821       revision 5.1 January 1998
1822    which SimonM says comes from the MS Developer Network CDs.
1823
1824    It can be found there (on older CDs), but can also be found
1825    online at:
1826
1827       http://www.microsoft.com/hwdev/hardware/PECOFF.asp
1828
1829    (this is Rev 6.0 from February 1999).
1830
1831    Things move, so if that fails, try searching for it via
1832
1833       http://www.google.com/search?q=PE+COFF+specification
1834
1835    The ultimate reference for the PE format is the Winnt.h
1836    header file that comes with the Platform SDKs; as always,
1837    implementations will drift wrt their documentation.
1838
1839    A good background article on the PE format is Matt Pietrek's
1840    March 1994 article in Microsoft System Journal (MSJ)
1841    (Vol.9, No. 3): "Peering Inside the PE: A Tour of the
1842    Win32 Portable Executable File Format." The info in there
1843    has recently been updated in a two part article in
1844    MSDN magazine, issues Feb and March 2002,
1845    "Inside Windows: An In-Depth Look into the Win32 Portable
1846    Executable File Format"
1847
1848    John Levine's book "Linkers and Loaders" contains useful
1849    info on PE too.
1850 */
1851
1852
1853 #if defined(OBJFORMAT_PEi386)
1854
1855
1856
1857 typedef unsigned char  UChar;
1858 typedef unsigned short UInt16;
1859 typedef unsigned int   UInt32;
1860 typedef          int   Int32;
1861
1862
1863 typedef
1864    struct {
1865       UInt16 Machine;
1866       UInt16 NumberOfSections;
1867       UInt32 TimeDateStamp;
1868       UInt32 PointerToSymbolTable;
1869       UInt32 NumberOfSymbols;
1870       UInt16 SizeOfOptionalHeader;
1871       UInt16 Characteristics;
1872    }
1873    COFF_header;
1874
1875 #define sizeof_COFF_header 20
1876
1877
1878 typedef
1879    struct {
1880       UChar  Name[8];
1881       UInt32 VirtualSize;
1882       UInt32 VirtualAddress;
1883       UInt32 SizeOfRawData;
1884       UInt32 PointerToRawData;
1885       UInt32 PointerToRelocations;
1886       UInt32 PointerToLinenumbers;
1887       UInt16 NumberOfRelocations;
1888       UInt16 NumberOfLineNumbers;
1889       UInt32 Characteristics;
1890    }
1891    COFF_section;
1892
1893 #define sizeof_COFF_section 40
1894
1895
1896 typedef
1897    struct {
1898       UChar  Name[8];
1899       UInt32 Value;
1900       UInt16 SectionNumber;
1901       UInt16 Type;
1902       UChar  StorageClass;
1903       UChar  NumberOfAuxSymbols;
1904    }
1905    COFF_symbol;
1906
1907 #define sizeof_COFF_symbol 18
1908
1909
1910 typedef
1911    struct {
1912       UInt32 VirtualAddress;
1913       UInt32 SymbolTableIndex;
1914       UInt16 Type;
1915    }
1916    COFF_reloc;
1917
1918 #define sizeof_COFF_reloc 10
1919
1920
1921 /* From PE spec doc, section 3.3.2 */
1922 /* Note use of MYIMAGE_* since IMAGE_* are already defined in
1923    windows.h -- for the same purpose, but I want to know what I'm
1924    getting, here. */
1925 #define MYIMAGE_FILE_RELOCS_STRIPPED     0x0001
1926 #define MYIMAGE_FILE_EXECUTABLE_IMAGE    0x0002
1927 #define MYIMAGE_FILE_DLL                 0x2000
1928 #define MYIMAGE_FILE_SYSTEM              0x1000
1929 #define MYIMAGE_FILE_BYTES_REVERSED_HI   0x8000
1930 #define MYIMAGE_FILE_BYTES_REVERSED_LO   0x0080
1931 #define MYIMAGE_FILE_32BIT_MACHINE       0x0100
1932
1933 /* From PE spec doc, section 5.4.2 and 5.4.4 */
1934 #define MYIMAGE_SYM_CLASS_EXTERNAL       2
1935 #define MYIMAGE_SYM_CLASS_STATIC         3
1936 #define MYIMAGE_SYM_UNDEFINED            0
1937
1938 /* From PE spec doc, section 4.1 */
1939 #define MYIMAGE_SCN_CNT_CODE             0x00000020
1940 #define MYIMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040
1941 #define MYIMAGE_SCN_LNK_NRELOC_OVFL      0x01000000
1942
1943 /* From PE spec doc, section 5.2.1 */
1944 #define MYIMAGE_REL_I386_DIR32           0x0006
1945 #define MYIMAGE_REL_I386_REL32           0x0014
1946
1947
1948 /* We use myindex to calculate array addresses, rather than
1949    simply doing the normal subscript thing.  That's because
1950    some of the above structs have sizes which are not
1951    a whole number of words.  GCC rounds their sizes up to a
1952    whole number of words, which means that the address calcs
1953    arising from using normal C indexing or pointer arithmetic
1954    are just plain wrong.  Sigh.
1955 */
1956 static UChar *
1957 myindex ( int scale, void* base, int index )
1958 {
1959    return
1960       ((UChar*)base) + scale * index;
1961 }
1962
1963
1964 static void
1965 printName ( UChar* name, UChar* strtab )
1966 {
1967    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1968       UInt32 strtab_offset = * (UInt32*)(name+4);
1969       debugBelch("%s", strtab + strtab_offset );
1970    } else {
1971       int i;
1972       for (i = 0; i < 8; i++) {
1973          if (name[i] == 0) break;
1974          debugBelch("%c", name[i] );
1975       }
1976    }
1977 }
1978
1979
1980 static void
1981 copyName ( UChar* name, UChar* strtab, UChar* dst, int dstSize )
1982 {
1983    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
1984       UInt32 strtab_offset = * (UInt32*)(name+4);
1985       strncpy ( dst, strtab+strtab_offset, dstSize );
1986       dst[dstSize-1] = 0;
1987    } else {
1988       int i = 0;
1989       while (1) {
1990          if (i >= 8) break;
1991          if (name[i] == 0) break;
1992          dst[i] = name[i];
1993          i++;
1994       }
1995       dst[i] = 0;
1996    }
1997 }
1998
1999
2000 static UChar *
2001 cstring_from_COFF_symbol_name ( UChar* name, UChar* strtab )
2002 {
2003    UChar* newstr;
2004    /* If the string is longer than 8 bytes, look in the
2005       string table for it -- this will be correctly zero terminated.
2006    */
2007    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
2008       UInt32 strtab_offset = * (UInt32*)(name+4);
2009       return ((UChar*)strtab) + strtab_offset;
2010    }
2011    /* Otherwise, if shorter than 8 bytes, return the original,
2012       which by defn is correctly terminated.
2013    */
2014    if (name[7]==0) return name;
2015    /* The annoying case: 8 bytes.  Copy into a temporary
2016       (which is never freed ...)
2017    */
2018    newstr = stgMallocBytes(9, "cstring_from_COFF_symbol_name");
2019    ASSERT(newstr);
2020    strncpy(newstr,name,8);
2021    newstr[8] = 0;
2022    return newstr;
2023 }
2024
2025
2026 /* Just compares the short names (first 8 chars) */
2027 static COFF_section *
2028 findPEi386SectionCalled ( ObjectCode* oc,  char* name )
2029 {
2030    int i;
2031    COFF_header* hdr
2032       = (COFF_header*)(oc->image);
2033    COFF_section* sectab
2034       = (COFF_section*) (
2035            ((UChar*)(oc->image))
2036            + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2037         );
2038    for (i = 0; i < hdr->NumberOfSections; i++) {
2039       UChar* n1;
2040       UChar* n2;
2041       COFF_section* section_i
2042          = (COFF_section*)
2043            myindex ( sizeof_COFF_section, sectab, i );
2044       n1 = (UChar*) &(section_i->Name);
2045       n2 = name;
2046       if (n1[0]==n2[0] && n1[1]==n2[1] && n1[2]==n2[2] &&
2047           n1[3]==n2[3] && n1[4]==n2[4] && n1[5]==n2[5] &&
2048           n1[6]==n2[6] && n1[7]==n2[7])
2049          return section_i;
2050    }
2051
2052    return NULL;
2053 }
2054
2055
2056 static void
2057 zapTrailingAtSign ( UChar* sym )
2058 {
2059 #  define my_isdigit(c) ((c) >= '0' && (c) <= '9')
2060    int i, j;
2061    if (sym[0] == 0) return;
2062    i = 0;
2063    while (sym[i] != 0) i++;
2064    i--;
2065    j = i;
2066    while (j > 0 && my_isdigit(sym[j])) j--;
2067    if (j > 0 && sym[j] == '@' && j != i) sym[j] = 0;
2068 #  undef my_isdigit
2069 }
2070
2071 static void *
2072 lookupSymbolInDLLs ( UChar *lbl )
2073 {
2074     OpenedDLL* o_dll;
2075     void *sym;
2076
2077     for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
2078         /* debugBelch("look in %s for %s\n", o_dll->name, lbl); */
2079
2080         if (lbl[0] == '_') {
2081             /* HACK: if the name has an initial underscore, try stripping
2082                it off & look that up first. I've yet to verify whether there's
2083                a Rule that governs whether an initial '_' *should always* be
2084                stripped off when mapping from import lib name to the DLL name.
2085             */
2086             sym = GetProcAddress(o_dll->instance, (lbl+1));
2087             if (sym != NULL) {
2088                 /*debugBelch("found %s in %s\n", lbl+1,o_dll->name);*/
2089                 return sym;
2090             }
2091         }
2092         sym = GetProcAddress(o_dll->instance, lbl);
2093         if (sym != NULL) {
2094             /*debugBelch("found %s in %s\n", lbl,o_dll->name);*/
2095             return sym;
2096            }
2097     }
2098     return NULL;
2099 }
2100
2101
2102 static int
2103 ocVerifyImage_PEi386 ( ObjectCode* oc )
2104 {
2105    int i;
2106    UInt32 j, noRelocs;
2107    COFF_header*  hdr;
2108    COFF_section* sectab;
2109    COFF_symbol*  symtab;
2110    UChar*        strtab;
2111    /* debugBelch("\nLOADING %s\n", oc->fileName); */
2112    hdr = (COFF_header*)(oc->image);
2113    sectab = (COFF_section*) (
2114                ((UChar*)(oc->image))
2115                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2116             );
2117    symtab = (COFF_symbol*) (
2118                ((UChar*)(oc->image))
2119                + hdr->PointerToSymbolTable
2120             );
2121    strtab = ((UChar*)symtab)
2122             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2123
2124    if (hdr->Machine != 0x14c) {
2125       errorBelch("%s: Not x86 PEi386", oc->fileName);
2126       return 0;
2127    }
2128    if (hdr->SizeOfOptionalHeader != 0) {
2129       errorBelch("%s: PEi386 with nonempty optional header", oc->fileName);
2130       return 0;
2131    }
2132    if ( /* (hdr->Characteristics & MYIMAGE_FILE_RELOCS_STRIPPED) || */
2133         (hdr->Characteristics & MYIMAGE_FILE_EXECUTABLE_IMAGE) ||
2134         (hdr->Characteristics & MYIMAGE_FILE_DLL) ||
2135         (hdr->Characteristics & MYIMAGE_FILE_SYSTEM) ) {
2136       errorBelch("%s: Not a PEi386 object file", oc->fileName);
2137       return 0;
2138    }
2139    if ( (hdr->Characteristics & MYIMAGE_FILE_BYTES_REVERSED_HI)
2140         /* || !(hdr->Characteristics & MYIMAGE_FILE_32BIT_MACHINE) */ ) {
2141       errorBelch("%s: Invalid PEi386 word size or endiannness: %d",
2142                  oc->fileName,
2143                  (int)(hdr->Characteristics));
2144       return 0;
2145    }
2146    /* If the string table size is way crazy, this might indicate that
2147       there are more than 64k relocations, despite claims to the
2148       contrary.  Hence this test. */
2149    /* debugBelch("strtab size %d\n", * (UInt32*)strtab); */
2150 #if 0
2151    if ( (*(UInt32*)strtab) > 600000 ) {
2152       /* Note that 600k has no special significance other than being
2153          big enough to handle the almost-2MB-sized lumps that
2154          constitute HSwin32*.o. */
2155       debugBelch("PEi386 object has suspiciously large string table; > 64k relocs?");
2156       return 0;
2157    }
2158 #endif
2159
2160    /* No further verification after this point; only debug printing. */
2161    i = 0;
2162    IF_DEBUG(linker, i=1);
2163    if (i == 0) return 1;
2164
2165    debugBelch( "sectab offset = %d\n", ((UChar*)sectab) - ((UChar*)hdr) );
2166    debugBelch( "symtab offset = %d\n", ((UChar*)symtab) - ((UChar*)hdr) );
2167    debugBelch( "strtab offset = %d\n", ((UChar*)strtab) - ((UChar*)hdr) );
2168
2169    debugBelch("\n" );
2170    debugBelch( "Machine:           0x%x\n", (UInt32)(hdr->Machine) );
2171    debugBelch( "# sections:        %d\n",   (UInt32)(hdr->NumberOfSections) );
2172    debugBelch( "time/date:         0x%x\n", (UInt32)(hdr->TimeDateStamp) );
2173    debugBelch( "symtab offset:     %d\n",   (UInt32)(hdr->PointerToSymbolTable) );
2174    debugBelch( "# symbols:         %d\n",   (UInt32)(hdr->NumberOfSymbols) );
2175    debugBelch( "sz of opt hdr:     %d\n",   (UInt32)(hdr->SizeOfOptionalHeader) );
2176    debugBelch( "characteristics:   0x%x\n", (UInt32)(hdr->Characteristics) );
2177
2178    /* Print the section table. */
2179    debugBelch("\n" );
2180    for (i = 0; i < hdr->NumberOfSections; i++) {
2181       COFF_reloc* reltab;
2182       COFF_section* sectab_i
2183          = (COFF_section*)
2184            myindex ( sizeof_COFF_section, sectab, i );
2185       debugBelch(
2186                 "\n"
2187                 "section %d\n"
2188                 "     name `",
2189                 i
2190               );
2191       printName ( sectab_i->Name, strtab );
2192       debugBelch(
2193                 "'\n"
2194                 "    vsize %d\n"
2195                 "    vaddr %d\n"
2196                 "  data sz %d\n"
2197                 " data off %d\n"
2198                 "  num rel %d\n"
2199                 "  off rel %d\n"
2200                 "  ptr raw 0x%x\n",
2201                 sectab_i->VirtualSize,
2202                 sectab_i->VirtualAddress,
2203                 sectab_i->SizeOfRawData,
2204                 sectab_i->PointerToRawData,
2205                 sectab_i->NumberOfRelocations,
2206                 sectab_i->PointerToRelocations,
2207                 sectab_i->PointerToRawData
2208               );
2209       reltab = (COFF_reloc*) (
2210                   ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2211                );
2212
2213       if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2214         /* If the relocation field (a short) has overflowed, the
2215          * real count can be found in the first reloc entry.
2216          *
2217          * See Section 4.1 (last para) of the PE spec (rev6.0).
2218          */
2219         COFF_reloc* rel = (COFF_reloc*)
2220                            myindex ( sizeof_COFF_reloc, reltab, 0 );
2221         noRelocs = rel->VirtualAddress;
2222         j = 1;
2223       } else {
2224         noRelocs = sectab_i->NumberOfRelocations;
2225         j = 0;
2226       }
2227
2228       for (; j < noRelocs; j++) {
2229          COFF_symbol* sym;
2230          COFF_reloc* rel = (COFF_reloc*)
2231                            myindex ( sizeof_COFF_reloc, reltab, j );
2232          debugBelch(
2233                    "        type 0x%-4x   vaddr 0x%-8x   name `",
2234                    (UInt32)rel->Type,
2235                    rel->VirtualAddress );
2236          sym = (COFF_symbol*)
2237                myindex ( sizeof_COFF_symbol, symtab, rel->SymbolTableIndex );
2238          /* Hmm..mysterious looking offset - what's it for? SOF */
2239          printName ( sym->Name, strtab -10 );
2240          debugBelch("'\n" );
2241       }
2242
2243       debugBelch("\n" );
2244    }
2245    debugBelch("\n" );
2246    debugBelch("string table has size 0x%x\n", * (UInt32*)strtab );
2247    debugBelch("---START of string table---\n");
2248    for (i = 4; i < *(Int32*)strtab; i++) {
2249       if (strtab[i] == 0)
2250          debugBelch("\n"); else
2251          debugBelch("%c", strtab[i] );
2252    }
2253    debugBelch("--- END  of string table---\n");
2254
2255    debugBelch("\n" );
2256    i = 0;
2257    while (1) {
2258       COFF_symbol* symtab_i;
2259       if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2260       symtab_i = (COFF_symbol*)
2261                  myindex ( sizeof_COFF_symbol, symtab, i );
2262       debugBelch(
2263                 "symbol %d\n"
2264                 "     name `",
2265                 i
2266               );
2267       printName ( symtab_i->Name, strtab );
2268       debugBelch(
2269                 "'\n"
2270                 "    value 0x%x\n"
2271                 "   1+sec# %d\n"
2272                 "     type 0x%x\n"
2273                 "   sclass 0x%x\n"
2274                 "     nAux %d\n",
2275                 symtab_i->Value,
2276                 (Int32)(symtab_i->SectionNumber),
2277                 (UInt32)symtab_i->Type,
2278                 (UInt32)symtab_i->StorageClass,
2279                 (UInt32)symtab_i->NumberOfAuxSymbols
2280               );
2281       i += symtab_i->NumberOfAuxSymbols;
2282       i++;
2283    }
2284
2285    debugBelch("\n" );
2286    return 1;
2287 }
2288
2289
2290 static int
2291 ocGetNames_PEi386 ( ObjectCode* oc )
2292 {
2293    COFF_header*  hdr;
2294    COFF_section* sectab;
2295    COFF_symbol*  symtab;
2296    UChar*        strtab;
2297
2298    UChar* sname;
2299    void*  addr;
2300    int    i;
2301
2302    hdr = (COFF_header*)(oc->image);
2303    sectab = (COFF_section*) (
2304                ((UChar*)(oc->image))
2305                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2306             );
2307    symtab = (COFF_symbol*) (
2308                ((UChar*)(oc->image))
2309                + hdr->PointerToSymbolTable
2310             );
2311    strtab = ((UChar*)(oc->image))
2312             + hdr->PointerToSymbolTable
2313             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2314
2315    /* Allocate space for any (local, anonymous) .bss sections. */
2316
2317    for (i = 0; i < hdr->NumberOfSections; i++) {
2318       UInt32 bss_sz;
2319       UChar* zspace;
2320       COFF_section* sectab_i
2321          = (COFF_section*)
2322            myindex ( sizeof_COFF_section, sectab, i );
2323       if (0 != strcmp(sectab_i->Name, ".bss")) continue;
2324       /* sof 10/05: the PE spec text isn't too clear regarding what
2325        * the SizeOfRawData field is supposed to hold for object
2326        * file sections containing just uninitialized data -- for executables,
2327        * it is supposed to be zero; unclear what it's supposed to be
2328        * for object files. However, VirtualSize is guaranteed to be
2329        * zero for object files, which definitely suggests that SizeOfRawData
2330        * will be non-zero (where else would the size of this .bss section be
2331        * stored?) Looking at the COFF_section info for incoming object files,
2332        * this certainly appears to be the case.
2333        *
2334        * => I suspect we've been incorrectly handling .bss sections in (relocatable)
2335        * object files up until now. This turned out to bite us with ghc-6.4.1's use
2336        * of gcc-3.4.x, which has started to emit initially-zeroed-out local 'static'
2337        * variable decls into to the .bss section. (The specific function in Q which
2338        * triggered this is libraries/base/cbits/dirUtils.c:__hscore_getFolderPath())
2339        */
2340       if (sectab_i->VirtualSize == 0 && sectab_i->SizeOfRawData == 0) continue;
2341       /* This is a non-empty .bss section.  Allocate zeroed space for
2342          it, and set its PointerToRawData field such that oc->image +
2343          PointerToRawData == addr_of_zeroed_space.  */
2344       bss_sz = sectab_i->VirtualSize;
2345       if ( bss_sz < sectab_i->SizeOfRawData) { bss_sz = sectab_i->SizeOfRawData; }
2346       zspace = stgCallocBytes(1, bss_sz, "ocGetNames_PEi386(anonymous bss)");
2347       sectab_i->PointerToRawData = ((UChar*)zspace) - ((UChar*)(oc->image));
2348       addProddableBlock(oc, zspace, bss_sz);
2349       /* debugBelch("BSS anon section at 0x%x\n", zspace); */
2350    }
2351
2352    /* Copy section information into the ObjectCode. */
2353
2354    for (i = 0; i < hdr->NumberOfSections; i++) {
2355       UChar* start;
2356       UChar* end;
2357       UInt32 sz;
2358
2359       SectionKind kind
2360          = SECTIONKIND_OTHER;
2361       COFF_section* sectab_i
2362          = (COFF_section*)
2363            myindex ( sizeof_COFF_section, sectab, i );
2364       IF_DEBUG(linker, debugBelch("section name = %s\n", sectab_i->Name ));
2365
2366 #     if 0
2367       /* I'm sure this is the Right Way to do it.  However, the
2368          alternative of testing the sectab_i->Name field seems to
2369          work ok with Cygwin.
2370       */
2371       if (sectab_i->Characteristics & MYIMAGE_SCN_CNT_CODE ||
2372           sectab_i->Characteristics & MYIMAGE_SCN_CNT_INITIALIZED_DATA)
2373          kind = SECTIONKIND_CODE_OR_RODATA;
2374 #     endif
2375
2376       if (0==strcmp(".text",sectab_i->Name) ||
2377           0==strcmp(".rdata",sectab_i->Name)||
2378           0==strcmp(".rodata",sectab_i->Name))
2379          kind = SECTIONKIND_CODE_OR_RODATA;
2380       if (0==strcmp(".data",sectab_i->Name) ||
2381           0==strcmp(".bss",sectab_i->Name))
2382          kind = SECTIONKIND_RWDATA;
2383
2384       ASSERT(sectab_i->SizeOfRawData == 0 || sectab_i->VirtualSize == 0);
2385       sz = sectab_i->SizeOfRawData;
2386       if (sz < sectab_i->VirtualSize) sz = sectab_i->VirtualSize;
2387
2388       start = ((UChar*)(oc->image)) + sectab_i->PointerToRawData;
2389       end   = start + sz - 1;
2390
2391       if (kind == SECTIONKIND_OTHER
2392           /* Ignore sections called which contain stabs debugging
2393              information. */
2394           && 0 != strcmp(".stab", sectab_i->Name)
2395           && 0 != strcmp(".stabstr", sectab_i->Name)
2396           /* ignore constructor section for now */
2397           && 0 != strcmp(".ctors", sectab_i->Name)
2398           /* ignore section generated from .ident */
2399           && 0!= strcmp("/4", sectab_i->Name)
2400           /* ignore unknown section that appeared in gcc 3.4.5(?) */
2401           && 0!= strcmp(".reloc", sectab_i->Name)
2402          ) {
2403          errorBelch("Unknown PEi386 section name `%s' (while processing: %s)", sectab_i->Name, oc->fileName);
2404          return 0;
2405       }
2406
2407       if (kind != SECTIONKIND_OTHER && end >= start) {
2408          addSection(oc, kind, start, end);
2409          addProddableBlock(oc, start, end - start + 1);
2410       }
2411    }
2412
2413    /* Copy exported symbols into the ObjectCode. */
2414
2415    oc->n_symbols = hdr->NumberOfSymbols;
2416    oc->symbols   = stgMallocBytes(oc->n_symbols * sizeof(char*),
2417                                   "ocGetNames_PEi386(oc->symbols)");
2418    /* Call me paranoid; I don't care. */
2419    for (i = 0; i < oc->n_symbols; i++)
2420       oc->symbols[i] = NULL;
2421
2422    i = 0;
2423    while (1) {
2424       COFF_symbol* symtab_i;
2425       if (i >= (Int32)(hdr->NumberOfSymbols)) break;
2426       symtab_i = (COFF_symbol*)
2427                  myindex ( sizeof_COFF_symbol, symtab, i );
2428
2429       addr  = NULL;
2430
2431       if (symtab_i->StorageClass == MYIMAGE_SYM_CLASS_EXTERNAL
2432           && symtab_i->SectionNumber != MYIMAGE_SYM_UNDEFINED) {
2433          /* This symbol is global and defined, viz, exported */
2434          /* for MYIMAGE_SYMCLASS_EXTERNAL
2435                 && !MYIMAGE_SYM_UNDEFINED,
2436             the address of the symbol is:
2437                 address of relevant section + offset in section
2438          */
2439          COFF_section* sectabent
2440             = (COFF_section*) myindex ( sizeof_COFF_section,
2441                                         sectab,
2442                                         symtab_i->SectionNumber-1 );
2443          addr = ((UChar*)(oc->image))
2444                 + (sectabent->PointerToRawData
2445                    + symtab_i->Value);
2446       }
2447       else
2448       if (symtab_i->SectionNumber == MYIMAGE_SYM_UNDEFINED
2449           && symtab_i->Value > 0) {
2450          /* This symbol isn't in any section at all, ie, global bss.
2451             Allocate zeroed space for it. */
2452          addr = stgCallocBytes(1, symtab_i->Value,
2453                                "ocGetNames_PEi386(non-anonymous bss)");
2454          addSection(oc, SECTIONKIND_RWDATA, addr,
2455                         ((UChar*)addr) + symtab_i->Value - 1);
2456          addProddableBlock(oc, addr, symtab_i->Value);
2457          /* debugBelch("BSS      section at 0x%x\n", addr); */
2458       }
2459
2460       if (addr != NULL ) {
2461          sname = cstring_from_COFF_symbol_name ( symtab_i->Name, strtab );
2462          /* debugBelch("addSymbol %p `%s \n", addr,sname);  */
2463          IF_DEBUG(linker, debugBelch("addSymbol %p `%s'\n", addr,sname);)
2464          ASSERT(i >= 0 && i < oc->n_symbols);
2465          /* cstring_from_COFF_symbol_name always succeeds. */
2466          oc->symbols[i] = sname;
2467          ghciInsertStrHashTable(oc->fileName, symhash, sname, addr);
2468       } else {
2469 #        if 0
2470          debugBelch(
2471                    "IGNORING symbol %d\n"
2472                    "     name `",
2473                    i
2474                  );
2475          printName ( symtab_i->Name, strtab );
2476          debugBelch(
2477                    "'\n"
2478                    "    value 0x%x\n"
2479                    "   1+sec# %d\n"
2480                    "     type 0x%x\n"
2481                    "   sclass 0x%x\n"
2482                    "     nAux %d\n",
2483                    symtab_i->Value,
2484                    (Int32)(symtab_i->SectionNumber),
2485                    (UInt32)symtab_i->Type,
2486                    (UInt32)symtab_i->StorageClass,
2487                    (UInt32)symtab_i->NumberOfAuxSymbols
2488                  );
2489 #        endif
2490       }
2491
2492       i += symtab_i->NumberOfAuxSymbols;
2493       i++;
2494    }
2495
2496    return 1;
2497 }
2498
2499
2500 static int
2501 ocResolve_PEi386 ( ObjectCode* oc )
2502 {
2503    COFF_header*  hdr;
2504    COFF_section* sectab;
2505    COFF_symbol*  symtab;
2506    UChar*        strtab;
2507
2508    UInt32        A;
2509    UInt32        S;
2510    UInt32*       pP;
2511
2512    int i;
2513    UInt32 j, noRelocs;
2514
2515    /* ToDo: should be variable-sized?  But is at least safe in the
2516       sense of buffer-overrun-proof. */
2517    char symbol[1000];
2518    /* debugBelch("resolving for %s\n", oc->fileName); */
2519
2520    hdr = (COFF_header*)(oc->image);
2521    sectab = (COFF_section*) (
2522                ((UChar*)(oc->image))
2523                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
2524             );
2525    symtab = (COFF_symbol*) (
2526                ((UChar*)(oc->image))
2527                + hdr->PointerToSymbolTable
2528             );
2529    strtab = ((UChar*)(oc->image))
2530             + hdr->PointerToSymbolTable
2531             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
2532
2533    for (i = 0; i < hdr->NumberOfSections; i++) {
2534       COFF_section* sectab_i
2535          = (COFF_section*)
2536            myindex ( sizeof_COFF_section, sectab, i );
2537       COFF_reloc* reltab
2538          = (COFF_reloc*) (
2539               ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
2540            );
2541
2542       /* Ignore sections called which contain stabs debugging
2543          information. */
2544       if (0 == strcmp(".stab", sectab_i->Name)
2545           || 0 == strcmp(".stabstr", sectab_i->Name)
2546           || 0 == strcmp(".ctors", sectab_i->Name))
2547          continue;
2548
2549       if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
2550         /* If the relocation field (a short) has overflowed, the
2551          * real count can be found in the first reloc entry.
2552          *
2553          * See Section 4.1 (last para) of the PE spec (rev6.0).
2554          *
2555          * Nov2003 update: the GNU linker still doesn't correctly
2556          * handle the generation of relocatable object files with
2557          * overflown relocations. Hence the output to warn of potential
2558          * troubles.
2559          */
2560         COFF_reloc* rel = (COFF_reloc*)
2561                            myindex ( sizeof_COFF_reloc, reltab, 0 );
2562         noRelocs = rel->VirtualAddress;
2563
2564         /* 10/05: we now assume (and check for) a GNU ld that is capable
2565          * of handling object files with (>2^16) of relocs.
2566          */
2567 #if 0
2568         debugBelch("WARNING: Overflown relocation field (# relocs found: %u)\n",
2569                    noRelocs);
2570 #endif
2571         j = 1;
2572       } else {
2573         noRelocs = sectab_i->NumberOfRelocations;
2574         j = 0;
2575       }
2576
2577
2578       for (; j < noRelocs; j++) {
2579          COFF_symbol* sym;
2580          COFF_reloc* reltab_j
2581             = (COFF_reloc*)
2582               myindex ( sizeof_COFF_reloc, reltab, j );
2583
2584          /* the location to patch */
2585          pP = (UInt32*)(
2586                  ((UChar*)(oc->image))
2587                  + (sectab_i->PointerToRawData
2588                     + reltab_j->VirtualAddress
2589                     - sectab_i->VirtualAddress )
2590               );
2591          /* the existing contents of pP */
2592          A = *pP;
2593          /* the symbol to connect to */
2594          sym = (COFF_symbol*)
2595                myindex ( sizeof_COFF_symbol,
2596                          symtab, reltab_j->SymbolTableIndex );
2597          IF_DEBUG(linker,
2598                   debugBelch(
2599                             "reloc sec %2d num %3d:  type 0x%-4x   "
2600                             "vaddr 0x%-8x   name `",
2601                             i, j,
2602                             (UInt32)reltab_j->Type,
2603                             reltab_j->VirtualAddress );
2604                             printName ( sym->Name, strtab );
2605                             debugBelch("'\n" ));
2606
2607          if (sym->StorageClass == MYIMAGE_SYM_CLASS_STATIC) {
2608             COFF_section* section_sym
2609                = findPEi386SectionCalled ( oc, sym->Name );
2610             if (!section_sym) {
2611                errorBelch("%s: can't find section `%s'", oc->fileName, sym->Name);
2612                return 0;
2613             }
2614             S = ((UInt32)(oc->image))
2615                 + (section_sym->PointerToRawData
2616                    + sym->Value);
2617          } else {
2618             copyName ( sym->Name, strtab, symbol, 1000-1 );
2619             S = (UInt32) lookupSymbol( symbol );
2620             if ((void*)S != NULL) goto foundit;
2621             errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
2622             return 0;
2623            foundit:;
2624          }
2625          checkProddableBlock(oc, pP);
2626          switch (reltab_j->Type) {
2627             case MYIMAGE_REL_I386_DIR32:
2628                *pP = A + S;
2629                break;
2630             case MYIMAGE_REL_I386_REL32:
2631                /* Tricky.  We have to insert a displacement at
2632                   pP which, when added to the PC for the _next_
2633                   insn, gives the address of the target (S).
2634                   Problem is to know the address of the next insn
2635                   when we only know pP.  We assume that this
2636                   literal field is always the last in the insn,
2637                   so that the address of the next insn is pP+4
2638                   -- hence the constant 4.
2639                   Also I don't know if A should be added, but so
2640                   far it has always been zero.
2641
2642                   SOF 05/2005: 'A' (old contents of *pP) have been observed
2643                   to contain values other than zero (the 'wx' object file
2644                   that came with wxhaskell-0.9.4; dunno how it was compiled..).
2645                   So, add displacement to old value instead of asserting
2646                   A to be zero. Fixes wxhaskell-related crashes, and no other
2647                   ill effects have been observed.
2648
2649                   Update: the reason why we're seeing these more elaborate
2650                   relocations is due to a switch in how the NCG compiles SRTs
2651                   and offsets to them from info tables. SRTs live in .(ro)data,
2652                   while info tables live in .text, causing GAS to emit REL32/DISP32
2653                   relocations with non-zero values. Adding the displacement is
2654                   the right thing to do.
2655                */
2656                *pP = S - ((UInt32)pP) - 4 + A;
2657                break;
2658             default:
2659                debugBelch("%s: unhandled PEi386 relocation type %d",
2660                      oc->fileName, reltab_j->Type);
2661                return 0;
2662          }
2663
2664       }
2665    }
2666
2667    IF_DEBUG(linker, debugBelch("completed %s", oc->fileName));
2668    return 1;
2669 }
2670
2671 #endif /* defined(OBJFORMAT_PEi386) */
2672
2673
2674 /* --------------------------------------------------------------------------
2675  * ELF specifics
2676  * ------------------------------------------------------------------------*/
2677
2678 #if defined(OBJFORMAT_ELF)
2679
2680 #define FALSE 0
2681 #define TRUE  1
2682
2683 #if defined(sparc_HOST_ARCH)
2684 #  define ELF_TARGET_SPARC  /* Used inside <elf.h> */
2685 #elif defined(i386_HOST_ARCH)
2686 #  define ELF_TARGET_386    /* Used inside <elf.h> */
2687 #elif defined(x86_64_HOST_ARCH)
2688 #  define ELF_TARGET_X64_64
2689 #  define ELF_64BIT
2690 #elif defined (ia64_HOST_ARCH)
2691 #  define ELF_TARGET_IA64   /* Used inside <elf.h> */
2692 #  define ELF_64BIT
2693 #  define ELF_FUNCTION_DESC /* calling convention uses function descriptors */
2694 #  define ELF_NEED_GOT      /* needs Global Offset Table */
2695 #  define ELF_NEED_PLT      /* needs Procedure Linkage Tables */
2696 #endif
2697
2698 #if !defined(openbsd_HOST_OS)
2699 #  include <elf.h>
2700 #else
2701 /* openbsd elf has things in different places, with diff names */
2702 #  include <elf_abi.h>
2703 #  include <machine/reloc.h>
2704 #  define R_386_32    RELOC_32
2705 #  define R_386_PC32  RELOC_PC32
2706 #endif
2707
2708 /* If elf.h doesn't define it */
2709 #  ifndef R_X86_64_PC64
2710 #    define R_X86_64_PC64 24
2711 #  endif
2712
2713 /*
2714  * Define a set of types which can be used for both ELF32 and ELF64
2715  */
2716
2717 #ifdef ELF_64BIT
2718 #define ELFCLASS    ELFCLASS64
2719 #define Elf_Addr    Elf64_Addr
2720 #define Elf_Word    Elf64_Word
2721 #define Elf_Sword   Elf64_Sword
2722 #define Elf_Ehdr    Elf64_Ehdr
2723 #define Elf_Phdr    Elf64_Phdr
2724 #define Elf_Shdr    Elf64_Shdr
2725 #define Elf_Sym     Elf64_Sym
2726 #define Elf_Rel     Elf64_Rel
2727 #define Elf_Rela    Elf64_Rela
2728 #define ELF_ST_TYPE ELF64_ST_TYPE
2729 #define ELF_ST_BIND ELF64_ST_BIND
2730 #define ELF_R_TYPE  ELF64_R_TYPE
2731 #define ELF_R_SYM   ELF64_R_SYM
2732 #else
2733 #define ELFCLASS    ELFCLASS32
2734 #define Elf_Addr    Elf32_Addr
2735 #define Elf_Word    Elf32_Word
2736 #define Elf_Sword   Elf32_Sword
2737 #define Elf_Ehdr    Elf32_Ehdr
2738 #define Elf_Phdr    Elf32_Phdr
2739 #define Elf_Shdr    Elf32_Shdr
2740 #define Elf_Sym     Elf32_Sym
2741 #define Elf_Rel     Elf32_Rel
2742 #define Elf_Rela    Elf32_Rela
2743 #ifndef ELF_ST_TYPE
2744 #define ELF_ST_TYPE ELF32_ST_TYPE
2745 #endif
2746 #ifndef ELF_ST_BIND
2747 #define ELF_ST_BIND ELF32_ST_BIND
2748 #endif
2749 #ifndef ELF_R_TYPE
2750 #define ELF_R_TYPE  ELF32_R_TYPE
2751 #endif
2752 #ifndef ELF_R_SYM
2753 #define ELF_R_SYM   ELF32_R_SYM
2754 #endif
2755 #endif
2756
2757
2758 /*
2759  * Functions to allocate entries in dynamic sections.  Currently we simply
2760  * preallocate a large number, and we don't check if a entry for the given
2761  * target already exists (a linear search is too slow).  Ideally these
2762  * entries would be associated with symbols.
2763  */
2764
2765 /* These sizes sufficient to load HSbase + HShaskell98 + a few modules */
2766 #define GOT_SIZE            0x20000
2767 #define FUNCTION_TABLE_SIZE 0x10000
2768 #define PLT_SIZE            0x08000
2769
2770 #ifdef ELF_NEED_GOT
2771 static Elf_Addr got[GOT_SIZE];
2772 static unsigned int gotIndex;
2773 static Elf_Addr gp_val = (Elf_Addr)got;
2774
2775 static Elf_Addr
2776 allocateGOTEntry(Elf_Addr target)
2777 {
2778    Elf_Addr *entry;
2779
2780    if (gotIndex >= GOT_SIZE)
2781       barf("Global offset table overflow");
2782
2783    entry = &got[gotIndex++];
2784    *entry = target;
2785    return (Elf_Addr)entry;
2786 }
2787 #endif
2788
2789 #ifdef ELF_FUNCTION_DESC
2790 typedef struct {
2791    Elf_Addr ip;
2792    Elf_Addr gp;
2793 } FunctionDesc;
2794
2795 static FunctionDesc functionTable[FUNCTION_TABLE_SIZE];
2796 static unsigned int functionTableIndex;
2797
2798 static Elf_Addr
2799 allocateFunctionDesc(Elf_Addr target)
2800 {
2801    FunctionDesc *entry;
2802
2803    if (functionTableIndex >= FUNCTION_TABLE_SIZE)
2804       barf("Function table overflow");
2805
2806    entry = &functionTable[functionTableIndex++];
2807    entry->ip = target;
2808    entry->gp = (Elf_Addr)gp_val;
2809    return (Elf_Addr)entry;
2810 }
2811
2812 static Elf_Addr
2813 copyFunctionDesc(Elf_Addr target)
2814 {
2815    FunctionDesc *olddesc = (FunctionDesc *)target;
2816    FunctionDesc *newdesc;
2817
2818    newdesc = (FunctionDesc *)allocateFunctionDesc(olddesc->ip);
2819    newdesc->gp = olddesc->gp;
2820    return (Elf_Addr)newdesc;
2821 }
2822 #endif
2823
2824 #ifdef ELF_NEED_PLT
2825 #ifdef ia64_HOST_ARCH
2826 static void ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value);
2827 static void ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc);
2828
2829 static unsigned char plt_code[] =
2830 {
2831    /* taken from binutils bfd/elfxx-ia64.c */
2832    0x0b, 0x78, 0x00, 0x02, 0x00, 0x24,  /*   [MMI]       addl r15=0,r1;;    */
2833    0x00, 0x41, 0x3c, 0x30, 0x28, 0xc0,  /*               ld8 r16=[r15],8    */
2834    0x01, 0x08, 0x00, 0x84,              /*               mov r14=r1;;       */
2835    0x11, 0x08, 0x00, 0x1e, 0x18, 0x10,  /*   [MIB]       ld8 r1=[r15]       */
2836    0x60, 0x80, 0x04, 0x80, 0x03, 0x00,  /*               mov b6=r16         */
2837    0x60, 0x00, 0x80, 0x00               /*               br.few b6;;        */
2838 };
2839
2840 /* If we can't get to the function descriptor via gp, take a local copy of it */
2841 #define PLT_RELOC(code, target) { \
2842    Elf64_Sxword rel_value = target - gp_val; \
2843    if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff)) \
2844       ia64_reloc_gprel22((Elf_Addr)code, copyFunctionDesc(target)); \
2845    else \
2846       ia64_reloc_gprel22((Elf_Addr)code, target); \
2847    }
2848 #endif
2849
2850 typedef struct {
2851    unsigned char code[sizeof(plt_code)];
2852 } PLTEntry;
2853
2854 static Elf_Addr
2855 allocatePLTEntry(Elf_Addr target, ObjectCode *oc)
2856 {
2857    PLTEntry *plt = (PLTEntry *)oc->plt;
2858    PLTEntry *entry;
2859
2860    if (oc->pltIndex >= PLT_SIZE)
2861       barf("Procedure table overflow");
2862
2863    entry = &plt[oc->pltIndex++];
2864    memcpy(entry->code, plt_code, sizeof(entry->code));
2865    PLT_RELOC(entry->code, target);
2866    return (Elf_Addr)entry;
2867 }
2868
2869 static unsigned int
2870 PLTSize(void)
2871 {
2872    return (PLT_SIZE * sizeof(PLTEntry));
2873 }
2874 #endif
2875
2876
2877 /*
2878  * Generic ELF functions
2879  */
2880
2881 static char *
2882 findElfSection ( void* objImage, Elf_Word sh_type )
2883 {
2884    char* ehdrC = (char*)objImage;
2885    Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2886    Elf_Shdr* shdr = (Elf_Shdr*)(ehdrC + ehdr->e_shoff);
2887    char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
2888    char* ptr = NULL;
2889    int i;
2890
2891    for (i = 0; i < ehdr->e_shnum; i++) {
2892       if (shdr[i].sh_type == sh_type
2893           /* Ignore the section header's string table. */
2894           && i != ehdr->e_shstrndx
2895           /* Ignore string tables named .stabstr, as they contain
2896              debugging info. */
2897           && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
2898          ) {
2899          ptr = ehdrC + shdr[i].sh_offset;
2900          break;
2901       }
2902    }
2903    return ptr;
2904 }
2905
2906 #if defined(ia64_HOST_ARCH)
2907 static Elf_Addr
2908 findElfSegment ( void* objImage, Elf_Addr vaddr )
2909 {
2910    char* ehdrC = (char*)objImage;
2911    Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
2912    Elf_Phdr* phdr = (Elf_Phdr*)(ehdrC + ehdr->e_phoff);
2913    Elf_Addr segaddr = 0;
2914    int i;
2915
2916    for (i = 0; i < ehdr->e_phnum; i++) {
2917       segaddr = phdr[i].p_vaddr;
2918       if ((vaddr >= segaddr) && (vaddr < segaddr + phdr[i].p_memsz))
2919               break;
2920    }
2921    return segaddr;
2922 }
2923 #endif
2924
2925 static int
2926 ocVerifyImage_ELF ( ObjectCode* oc )
2927 {
2928    Elf_Shdr* shdr;
2929    Elf_Sym*  stab;
2930    int i, j, nent, nstrtab, nsymtabs;
2931    char* sh_strtab;
2932    char* strtab;
2933
2934    char*     ehdrC = (char*)(oc->image);
2935    Elf_Ehdr* ehdr  = (Elf_Ehdr*)ehdrC;
2936
2937    if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
2938        ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
2939        ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
2940        ehdr->e_ident[EI_MAG3] != ELFMAG3) {
2941       errorBelch("%s: not an ELF object", oc->fileName);
2942       return 0;
2943    }
2944
2945    if (ehdr->e_ident[EI_CLASS] != ELFCLASS) {
2946       errorBelch("%s: unsupported ELF format", oc->fileName);
2947       return 0;
2948    }
2949
2950    if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) {
2951        IF_DEBUG(linker,debugBelch( "Is little-endian\n" ));
2952    } else
2953    if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) {
2954        IF_DEBUG(linker,debugBelch( "Is big-endian\n" ));
2955    } else {
2956        errorBelch("%s: unknown endiannness", oc->fileName);
2957        return 0;
2958    }
2959
2960    if (ehdr->e_type != ET_REL) {
2961       errorBelch("%s: not a relocatable object (.o) file", oc->fileName);
2962       return 0;
2963    }
2964    IF_DEBUG(linker, debugBelch( "Is a relocatable object (.o) file\n" ));
2965
2966    IF_DEBUG(linker,debugBelch( "Architecture is " ));
2967    switch (ehdr->e_machine) {
2968       case EM_386:   IF_DEBUG(linker,debugBelch( "x86" )); break;
2969 #ifdef EM_SPARC32PLUS
2970       case EM_SPARC32PLUS:
2971 #endif
2972       case EM_SPARC: IF_DEBUG(linker,debugBelch( "sparc" )); break;
2973 #ifdef EM_IA_64
2974       case EM_IA_64: IF_DEBUG(linker,debugBelch( "ia64" )); break;
2975 #endif
2976       case EM_PPC:   IF_DEBUG(linker,debugBelch( "powerpc32" )); break;
2977 #ifdef EM_X86_64
2978       case EM_X86_64: IF_DEBUG(linker,debugBelch( "x86_64" )); break;
2979 #elif defined(EM_AMD64)
2980       case EM_AMD64: IF_DEBUG(linker,debugBelch( "amd64" )); break;
2981 #endif
2982       default:       IF_DEBUG(linker,debugBelch( "unknown" ));
2983                      errorBelch("%s: unknown architecture (e_machine == %d)"
2984                                 , oc->fileName, ehdr->e_machine);
2985                      return 0;
2986    }
2987
2988    IF_DEBUG(linker,debugBelch(
2989              "\nSection header table: start %ld, n_entries %d, ent_size %d\n",
2990              (long)ehdr->e_shoff, ehdr->e_shnum, ehdr->e_shentsize  ));
2991
2992    ASSERT (ehdr->e_shentsize == sizeof(Elf_Shdr));
2993
2994    shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
2995
2996    if (ehdr->e_shstrndx == SHN_UNDEF) {
2997       errorBelch("%s: no section header string table", oc->fileName);
2998       return 0;
2999    } else {
3000       IF_DEBUG(linker,debugBelch( "Section header string table is section %d\n",
3001                           ehdr->e_shstrndx));
3002       sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
3003    }
3004
3005    for (i = 0; i < ehdr->e_shnum; i++) {
3006       IF_DEBUG(linker,debugBelch("%2d:  ", i ));
3007       IF_DEBUG(linker,debugBelch("type=%2d  ", (int)shdr[i].sh_type ));
3008       IF_DEBUG(linker,debugBelch("size=%4d  ", (int)shdr[i].sh_size ));
3009       IF_DEBUG(linker,debugBelch("offs=%4d  ", (int)shdr[i].sh_offset ));
3010       IF_DEBUG(linker,debugBelch("  (%p .. %p)  ",
3011                ehdrC + shdr[i].sh_offset,
3012                       ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1));
3013
3014       if (shdr[i].sh_type == SHT_REL) {
3015           IF_DEBUG(linker,debugBelch("Rel  " ));
3016       } else if (shdr[i].sh_type == SHT_RELA) {
3017           IF_DEBUG(linker,debugBelch("RelA " ));
3018       } else {
3019           IF_DEBUG(linker,debugBelch("     "));
3020       }
3021       if (sh_strtab) {
3022           IF_DEBUG(linker,debugBelch("sname=%s\n", sh_strtab + shdr[i].sh_name ));
3023       }
3024    }
3025
3026    IF_DEBUG(linker,debugBelch( "\nString tables" ));
3027    strtab = NULL;
3028    nstrtab = 0;
3029    for (i = 0; i < ehdr->e_shnum; i++) {
3030       if (shdr[i].sh_type == SHT_STRTAB
3031           /* Ignore the section header's string table. */
3032           && i != ehdr->e_shstrndx
3033           /* Ignore string tables named .stabstr, as they contain
3034              debugging info. */
3035           && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
3036          ) {
3037          IF_DEBUG(linker,debugBelch("   section %d is a normal string table", i ));
3038          strtab = ehdrC + shdr[i].sh_offset;
3039          nstrtab++;
3040       }
3041    }
3042    if (nstrtab != 1) {
3043       errorBelch("%s: no string tables, or too many", oc->fileName);
3044       return 0;
3045    }
3046
3047    nsymtabs = 0;
3048    IF_DEBUG(linker,debugBelch( "\nSymbol tables" ));
3049    for (i = 0; i < ehdr->e_shnum; i++) {
3050       if (shdr[i].sh_type != SHT_SYMTAB) continue;
3051       IF_DEBUG(linker,debugBelch( "section %d is a symbol table\n", i ));
3052       nsymtabs++;
3053       stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
3054       nent = shdr[i].sh_size / sizeof(Elf_Sym);
3055       IF_DEBUG(linker,debugBelch( "   number of entries is apparently %d (%ld rem)\n",
3056                nent,
3057                (long)shdr[i].sh_size % sizeof(Elf_Sym)
3058              ));
3059       if (0 != shdr[i].sh_size % sizeof(Elf_Sym)) {
3060          errorBelch("%s: non-integral number of symbol table entries", oc->fileName);
3061          return 0;
3062       }
3063       for (j = 0; j < nent; j++) {
3064          IF_DEBUG(linker,debugBelch("   %2d  ", j ));
3065          IF_DEBUG(linker,debugBelch("  sec=%-5d  size=%-3d  val=%5p  ",
3066                              (int)stab[j].st_shndx,
3067                              (int)stab[j].st_size,
3068                              (char*)stab[j].st_value ));
3069
3070          IF_DEBUG(linker,debugBelch("type=" ));
3071          switch (ELF_ST_TYPE(stab[j].st_info)) {
3072             case STT_NOTYPE:  IF_DEBUG(linker,debugBelch("notype " )); break;
3073             case STT_OBJECT:  IF_DEBUG(linker,debugBelch("object " )); break;
3074             case STT_FUNC  :  IF_DEBUG(linker,debugBelch("func   " )); break;
3075             case STT_SECTION: IF_DEBUG(linker,debugBelch("section" )); break;
3076             case STT_FILE:    IF_DEBUG(linker,debugBelch("file   " )); break;
3077             default:          IF_DEBUG(linker,debugBelch("?      " )); break;
3078          }
3079          IF_DEBUG(linker,debugBelch("  " ));
3080
3081          IF_DEBUG(linker,debugBelch("bind=" ));
3082          switch (ELF_ST_BIND(stab[j].st_info)) {
3083             case STB_LOCAL :  IF_DEBUG(linker,debugBelch("local " )); break;
3084             case STB_GLOBAL:  IF_DEBUG(linker,debugBelch("global" )); break;
3085             case STB_WEAK  :  IF_DEBUG(linker,debugBelch("weak  " )); break;
3086             default:          IF_DEBUG(linker,debugBelch("?     " )); break;
3087          }
3088          IF_DEBUG(linker,debugBelch("  " ));
3089
3090          IF_DEBUG(linker,debugBelch("name=%s\n", strtab + stab[j].st_name ));
3091       }
3092    }
3093
3094    if (nsymtabs == 0) {
3095       errorBelch("%s: didn't find any symbol tables", oc->fileName);
3096       return 0;
3097    }
3098
3099    return 1;
3100 }
3101
3102 static int getSectionKind_ELF( Elf_Shdr *hdr, int *is_bss )
3103 {
3104     *is_bss = FALSE;
3105
3106     if (hdr->sh_type == SHT_PROGBITS
3107         && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_EXECINSTR)) {
3108         /* .text-style section */
3109         return SECTIONKIND_CODE_OR_RODATA;
3110     }
3111
3112     if (hdr->sh_type == SHT_PROGBITS
3113             && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
3114             /* .data-style section */
3115             return SECTIONKIND_RWDATA;
3116     }
3117
3118     if (hdr->sh_type == SHT_PROGBITS
3119         && (hdr->sh_flags & SHF_ALLOC) && !(hdr->sh_flags & SHF_WRITE)) {
3120         /* .rodata-style section */
3121         return SECTIONKIND_CODE_OR_RODATA;
3122     }
3123
3124     if (hdr->sh_type == SHT_NOBITS
3125         && (hdr->sh_flags & SHF_ALLOC) && (hdr->sh_flags & SHF_WRITE)) {
3126         /* .bss-style section */
3127         *is_bss = TRUE;
3128         return SECTIONKIND_RWDATA;
3129     }
3130
3131     return SECTIONKIND_OTHER;
3132 }
3133
3134
3135 static int
3136 ocGetNames_ELF ( ObjectCode* oc )
3137 {
3138    int i, j, k, nent;
3139    Elf_Sym* stab;
3140
3141    char*     ehdrC    = (char*)(oc->image);
3142    Elf_Ehdr* ehdr     = (Elf_Ehdr*)ehdrC;
3143    char*     strtab   = findElfSection ( ehdrC, SHT_STRTAB );
3144    Elf_Shdr* shdr     = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3145
3146    ASSERT(symhash != NULL);
3147
3148    if (!strtab) {
3149       errorBelch("%s: no strtab", oc->fileName);
3150       return 0;
3151    }
3152
3153    k = 0;
3154    for (i = 0; i < ehdr->e_shnum; i++) {
3155       /* Figure out what kind of section it is.  Logic derived from
3156          Figure 1.14 ("Special Sections") of the ELF document
3157          ("Portable Formats Specification, Version 1.1"). */
3158       int         is_bss = FALSE;
3159       SectionKind kind   = getSectionKind_ELF(&shdr[i], &is_bss);
3160
3161       if (is_bss && shdr[i].sh_size > 0) {
3162          /* This is a non-empty .bss section.  Allocate zeroed space for
3163             it, and set its .sh_offset field such that
3164             ehdrC + .sh_offset == addr_of_zeroed_space.  */
3165          char* zspace = stgCallocBytes(1, shdr[i].sh_size,
3166                                        "ocGetNames_ELF(BSS)");
3167          shdr[i].sh_offset = ((char*)zspace) - ((char*)ehdrC);
3168          /*
3169          debugBelch("BSS section at 0x%x, size %d\n",
3170                          zspace, shdr[i].sh_size);
3171          */
3172       }
3173
3174       /* fill in the section info */
3175       if (kind != SECTIONKIND_OTHER && shdr[i].sh_size > 0) {
3176          addProddableBlock(oc, ehdrC + shdr[i].sh_offset, shdr[i].sh_size);
3177          addSection(oc, kind, ehdrC + shdr[i].sh_offset,
3178                         ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1);
3179       }
3180
3181       if (shdr[i].sh_type != SHT_SYMTAB) continue;
3182
3183       /* copy stuff into this module's object symbol table */
3184       stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
3185       nent = shdr[i].sh_size / sizeof(Elf_Sym);
3186
3187       oc->n_symbols = nent;
3188       oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
3189                                    "ocGetNames_ELF(oc->symbols)");
3190
3191       for (j = 0; j < nent; j++) {
3192
3193          char  isLocal = FALSE; /* avoids uninit-var warning */
3194          char* ad      = NULL;
3195          char* nm      = strtab + stab[j].st_name;
3196          int   secno   = stab[j].st_shndx;
3197
3198          /* Figure out if we want to add it; if so, set ad to its
3199             address.  Otherwise leave ad == NULL. */
3200
3201          if (secno == SHN_COMMON) {
3202             isLocal = FALSE;
3203             ad = stgCallocBytes(1, stab[j].st_size, "ocGetNames_ELF(COMMON)");
3204             /*
3205             debugBelch("COMMON symbol, size %d name %s\n",
3206                             stab[j].st_size, nm);
3207             */
3208             /* Pointless to do addProddableBlock() for this area,
3209                since the linker should never poke around in it. */
3210          }
3211          else
3212          if ( ( ELF_ST_BIND(stab[j].st_info)==STB_GLOBAL
3213                 || ELF_ST_BIND(stab[j].st_info)==STB_LOCAL
3214               )
3215               /* and not an undefined symbol */
3216               && stab[j].st_shndx != SHN_UNDEF
3217               /* and not in a "special section" */
3218               && stab[j].st_shndx < SHN_LORESERVE
3219               &&
3220               /* and it's a not a section or string table or anything silly */
3221               ( ELF_ST_TYPE(stab[j].st_info)==STT_FUNC ||
3222                 ELF_ST_TYPE(stab[j].st_info)==STT_OBJECT ||
3223                 ELF_ST_TYPE(stab[j].st_info)==STT_NOTYPE
3224               )
3225             ) {
3226             /* Section 0 is the undefined section, hence > and not >=. */
3227             ASSERT(secno > 0 && secno < ehdr->e_shnum);
3228             /*
3229             if (shdr[secno].sh_type == SHT_NOBITS) {
3230                debugBelch("   BSS symbol, size %d off %d name %s\n",
3231                                stab[j].st_size, stab[j].st_value, nm);
3232             }
3233             */
3234             ad = ehdrC + shdr[ secno ].sh_offset + stab[j].st_value;
3235             if (ELF_ST_BIND(stab[j].st_info)==STB_LOCAL) {
3236                isLocal = TRUE;
3237             } else {
3238 #ifdef ELF_FUNCTION_DESC
3239                /* dlsym() and the initialisation table both give us function
3240                 * descriptors, so to be consistent we store function descriptors
3241                 * in the symbol table */
3242                if (ELF_ST_TYPE(stab[j].st_info) == STT_FUNC)
3243                    ad = (char *)allocateFunctionDesc((Elf_Addr)ad);
3244 #endif
3245                IF_DEBUG(linker,debugBelch( "addOTabName(GLOB): %10p  %s %s\n",
3246                                       ad, oc->fileName, nm ));
3247                isLocal = FALSE;
3248             }
3249          }
3250
3251          /* And the decision is ... */
3252
3253          if (ad != NULL) {
3254             ASSERT(nm != NULL);
3255             oc->symbols[j] = nm;
3256             /* Acquire! */
3257             if (isLocal) {
3258                /* Ignore entirely. */
3259             } else {
3260                ghciInsertStrHashTable(oc->fileName, symhash, nm, ad);
3261             }
3262          } else {
3263             /* Skip. */
3264             IF_DEBUG(linker,debugBelch( "skipping `%s'\n",
3265                                    strtab + stab[j].st_name ));
3266             /*
3267             debugBelch(
3268                     "skipping   bind = %d,  type = %d,  shndx = %d   `%s'\n",
3269                     (int)ELF_ST_BIND(stab[j].st_info),
3270                     (int)ELF_ST_TYPE(stab[j].st_info),
3271                     (int)stab[j].st_shndx,
3272                     strtab + stab[j].st_name
3273                    );
3274             */
3275             oc->symbols[j] = NULL;
3276          }
3277
3278       }
3279    }
3280
3281    return 1;
3282 }
3283
3284 /* Do ELF relocations which lack an explicit addend.  All x86-linux
3285    relocations appear to be of this form. */
3286 static int
3287 do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
3288                          Elf_Shdr* shdr, int shnum,
3289                          Elf_Sym*  stab, char* strtab )
3290 {
3291    int j;
3292    char *symbol;
3293    Elf_Word* targ;
3294    Elf_Rel*  rtab = (Elf_Rel*) (ehdrC + shdr[shnum].sh_offset);
3295    int         nent = shdr[shnum].sh_size / sizeof(Elf_Rel);
3296    int target_shndx = shdr[shnum].sh_info;
3297    int symtab_shndx = shdr[shnum].sh_link;
3298
3299    stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3300    targ  = (Elf_Word*)(ehdrC + shdr[ target_shndx ].sh_offset);
3301    IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3302                           target_shndx, symtab_shndx ));
3303
3304    /* Skip sections that we're not interested in. */
3305    {
3306        int is_bss;
3307        SectionKind kind = getSectionKind_ELF(&shdr[target_shndx], &is_bss);
3308        if (kind == SECTIONKIND_OTHER) {
3309            IF_DEBUG(linker,debugBelch( "skipping (target section not loaded)"));
3310            return 1;
3311        }
3312    }
3313
3314    for (j = 0; j < nent; j++) {
3315       Elf_Addr offset = rtab[j].r_offset;
3316       Elf_Addr info   = rtab[j].r_info;
3317
3318       Elf_Addr  P  = ((Elf_Addr)targ) + offset;
3319       Elf_Word* pP = (Elf_Word*)P;
3320       Elf_Addr  A  = *pP;
3321       Elf_Addr  S;
3322       void*     S_tmp;
3323       Elf_Addr  value;
3324       StgStablePtr stablePtr;
3325       StgPtr stableVal;
3326
3327       IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p)",
3328                              j, (void*)offset, (void*)info ));
3329       if (!info) {
3330          IF_DEBUG(linker,debugBelch( " ZERO" ));
3331          S = 0;
3332       } else {
3333          Elf_Sym sym = stab[ELF_R_SYM(info)];
3334          /* First see if it is a local symbol. */
3335          if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3336             /* Yes, so we can get the address directly from the ELF symbol
3337                table. */
3338             symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3339             S = (Elf_Addr)
3340                 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3341                        + stab[ELF_R_SYM(info)].st_value);
3342
3343          } else {
3344             symbol = strtab + sym.st_name;
3345             stablePtr = (StgStablePtr)lookupHashTable(stablehash, (StgWord)symbol);
3346             if (NULL == stablePtr) {
3347               /* No, so look up the name in our global table. */
3348               S_tmp = lookupSymbol( symbol );
3349               S = (Elf_Addr)S_tmp;
3350             } else {
3351               stableVal = deRefStablePtr( stablePtr );
3352               S_tmp = stableVal;
3353               S = (Elf_Addr)S_tmp;
3354             }
3355          }
3356          if (!S) {
3357             errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3358             return 0;
3359          }
3360          IF_DEBUG(linker,debugBelch( "`%s' resolves to %p\n", symbol, (void*)S ));
3361       }
3362
3363       IF_DEBUG(linker,debugBelch( "Reloc: P = %p   S = %p   A = %p\n",
3364                              (void*)P, (void*)S, (void*)A ));
3365       checkProddableBlock ( oc, pP );
3366
3367       value = S + A;
3368
3369       switch (ELF_R_TYPE(info)) {
3370 #        ifdef i386_HOST_ARCH
3371          case R_386_32:   *pP = value;     break;
3372          case R_386_PC32: *pP = value - P; break;
3373 #        endif
3374          default:
3375             errorBelch("%s: unhandled ELF relocation(Rel) type %lu\n",
3376                   oc->fileName, (lnat)ELF_R_TYPE(info));
3377             return 0;
3378       }
3379
3380    }
3381    return 1;
3382 }
3383
3384 /* Do ELF relocations for which explicit addends are supplied.
3385    sparc-solaris relocations appear to be of this form. */
3386 static int
3387 do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
3388                           Elf_Shdr* shdr, int shnum,
3389                           Elf_Sym*  stab, char* strtab )
3390 {
3391    int j;
3392    char *symbol = NULL;
3393    Elf_Addr targ;
3394    Elf_Rela* rtab = (Elf_Rela*) (ehdrC + shdr[shnum].sh_offset);
3395    int         nent = shdr[shnum].sh_size / sizeof(Elf_Rela);
3396    int target_shndx = shdr[shnum].sh_info;
3397    int symtab_shndx = shdr[shnum].sh_link;
3398
3399    stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
3400    targ  = (Elf_Addr) (ehdrC + shdr[ target_shndx ].sh_offset);
3401    IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
3402                           target_shndx, symtab_shndx ));
3403
3404    for (j = 0; j < nent; j++) {
3405 #if defined(DEBUG) || defined(sparc_HOST_ARCH) || defined(ia64_HOST_ARCH) || defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
3406       /* This #ifdef only serves to avoid unused-var warnings. */
3407       Elf_Addr  offset = rtab[j].r_offset;
3408       Elf_Addr  P      = targ + offset;
3409 #endif
3410       Elf_Addr  info   = rtab[j].r_info;
3411       Elf_Addr  A      = rtab[j].r_addend;
3412       Elf_Addr  S;
3413       void*     S_tmp;
3414       Elf_Addr  value;
3415 #     if defined(sparc_HOST_ARCH)
3416       Elf_Word* pP = (Elf_Word*)P;
3417       Elf_Word  w1, w2;
3418 #     elif defined(ia64_HOST_ARCH)
3419       Elf64_Xword *pP = (Elf64_Xword *)P;
3420       Elf_Addr addr;
3421 #     elif defined(powerpc_HOST_ARCH)
3422       Elf_Sword delta;
3423 #     endif
3424
3425       IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p %6p)   ",
3426                              j, (void*)offset, (void*)info,
3427                                 (void*)A ));
3428       if (!info) {
3429          IF_DEBUG(linker,debugBelch( " ZERO" ));
3430          S = 0;
3431       } else {
3432          Elf_Sym sym = stab[ELF_R_SYM(info)];
3433          /* First see if it is a local symbol. */
3434          if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
3435             /* Yes, so we can get the address directly from the ELF symbol
3436                table. */
3437             symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
3438             S = (Elf_Addr)
3439                 (ehdrC + shdr[ sym.st_shndx ].sh_offset
3440                        + stab[ELF_R_SYM(info)].st_value);
3441 #ifdef ELF_FUNCTION_DESC
3442             /* Make a function descriptor for this function */
3443             if (S && ELF_ST_TYPE(sym.st_info) == STT_FUNC) {
3444                S = allocateFunctionDesc(S + A);
3445                A = 0;
3446             }
3447 #endif
3448          } else {
3449             /* No, so look up the name in our global table. */
3450             symbol = strtab + sym.st_name;
3451             S_tmp = lookupSymbol( symbol );
3452             S = (Elf_Addr)S_tmp;
3453
3454 #ifdef ELF_FUNCTION_DESC
3455             /* If a function, already a function descriptor - we would
3456                have to copy it to add an offset. */
3457             if (S && (ELF_ST_TYPE(sym.st_info) == STT_FUNC) && (A != 0))
3458                errorBelch("%s: function %s with addend %p", oc->fileName, symbol, (void *)A);
3459 #endif
3460          }
3461          if (!S) {
3462            errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
3463            return 0;
3464          }
3465          IF_DEBUG(linker,debugBelch( "`%s' resolves to %p", symbol, (void*)S ));
3466       }
3467
3468       IF_DEBUG(linker,debugBelch("Reloc: P = %p   S = %p   A = %p\n",
3469                                         (void*)P, (void*)S, (void*)A ));
3470       /* checkProddableBlock ( oc, (void*)P ); */
3471
3472       value = S + A;
3473
3474       switch (ELF_R_TYPE(info)) {
3475 #        if defined(sparc_HOST_ARCH)
3476          case R_SPARC_WDISP30:
3477             w1 = *pP & 0xC0000000;
3478             w2 = (Elf_Word)((value - P) >> 2);
3479             ASSERT((w2 & 0xC0000000) == 0);
3480             w1 |= w2;
3481             *pP = w1;
3482             break;
3483          case R_SPARC_HI22:
3484             w1 = *pP & 0xFFC00000;
3485             w2 = (Elf_Word)(value >> 10);
3486             ASSERT((w2 & 0xFFC00000) == 0);
3487             w1 |= w2;
3488             *pP = w1;
3489             break;
3490          case R_SPARC_LO10:
3491             w1 = *pP & ~0x3FF;
3492             w2 = (Elf_Word)(value & 0x3FF);
3493             ASSERT((w2 & ~0x3FF) == 0);
3494             w1 |= w2;
3495             *pP = w1;
3496             break;
3497
3498          /* According to the Sun documentation:
3499             R_SPARC_UA32
3500             This relocation type resembles R_SPARC_32, except it refers to an
3501             unaligned word. That is, the word to be relocated must be treated
3502             as four separate bytes with arbitrary alignment, not as a word
3503             aligned according to the architecture requirements.
3504          */
3505          case R_SPARC_UA32:
3506             w2  = (Elf_Word)value;
3507
3508             // SPARC doesn't do misaligned writes of 32 bit words,
3509             //       so we have to do this one byte-at-a-time.
3510             char *pPc   = (char*)pP;
3511             pPc[0]      = (char) ((Elf_Word)(w2 & 0xff000000) >> 24);
3512             pPc[1]      = (char) ((Elf_Word)(w2 & 0x00ff0000) >> 16);
3513             pPc[2]      = (char) ((Elf_Word)(w2 & 0x0000ff00) >> 8);
3514             pPc[3]      = (char) ((Elf_Word)(w2 & 0x000000ff));
3515             break;
3516
3517          case R_SPARC_32:
3518             w2 = (Elf_Word)value;
3519             *pP = w2;
3520             break;
3521 #        elif defined(ia64_HOST_ARCH)
3522          case R_IA64_DIR64LSB:
3523          case R_IA64_FPTR64LSB:
3524             *pP = value;
3525             break;
3526          case R_IA64_PCREL64LSB:
3527             *pP = value - P;
3528             break;
3529          case R_IA64_SEGREL64LSB:
3530             addr = findElfSegment(ehdrC, value);
3531             *pP = value - addr;
3532             break;
3533          case R_IA64_GPREL22:
3534             ia64_reloc_gprel22(P, value);
3535             break;
3536          case R_IA64_LTOFF22:
3537          case R_IA64_LTOFF22X:
3538          case R_IA64_LTOFF_FPTR22:
3539             addr = allocateGOTEntry(value);
3540             ia64_reloc_gprel22(P, addr);
3541             break;
3542          case R_IA64_PCREL21B:
3543             ia64_reloc_pcrel21(P, S, oc);
3544             break;
3545          case R_IA64_LDXMOV:
3546             /* This goes with R_IA64_LTOFF22X and points to the load to
3547              * convert into a move.  We don't implement relaxation. */
3548             break;
3549 #        elif defined(powerpc_HOST_ARCH)
3550          case R_PPC_ADDR16_LO:
3551             *(Elf32_Half*) P = value;
3552             break;
3553
3554          case R_PPC_ADDR16_HI:
3555             *(Elf32_Half*) P = value >> 16;
3556             break;
3557
3558          case R_PPC_ADDR16_HA:
3559             *(Elf32_Half*) P = (value + 0x8000) >> 16;
3560             break;
3561
3562          case R_PPC_ADDR32:
3563             *(Elf32_Word *) P = value;
3564             break;
3565
3566          case R_PPC_REL32:
3567             *(Elf32_Word *) P = value - P;
3568             break;
3569
3570          case R_PPC_REL24:
3571             delta = value - P;
3572
3573             if( delta << 6 >> 6 != delta )
3574             {
3575                value = (Elf_Addr) (&makeSymbolExtra( oc, ELF_R_SYM(info), value )
3576                                         ->jumpIsland);
3577                delta = value - P;
3578
3579                if( value == 0 || delta << 6 >> 6 != delta )
3580                {
3581                   barf( "Unable to make SymbolExtra for #%d",
3582                         ELF_R_SYM(info) );
3583                   return 0;
3584                }
3585             }
3586
3587             *(Elf_Word *) P = (*(Elf_Word *) P & 0xfc000003)
3588                                           | (delta & 0x3fffffc);
3589             break;
3590 #        endif
3591
3592 #if x86_64_HOST_ARCH
3593       case R_X86_64_64:
3594           *(Elf64_Xword *)P = value;
3595           break;
3596
3597       case R_X86_64_PC32:
3598       {
3599           StgInt64 off = value - P;
3600           if (off >= 0x7fffffffL || off < -0x80000000L) {
3601 #if X86_64_ELF_NONPIC_HACK
3602               StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3603                                                 -> jumpIsland;
3604               off = pltAddress + A - P;
3605 #else
3606               barf("R_X86_64_PC32 relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3607                    symbol, off, oc->fileName );
3608 #endif
3609           }
3610           *(Elf64_Word *)P = (Elf64_Word)off;
3611           break;
3612       }
3613
3614       case R_X86_64_PC64:
3615       {
3616           StgInt64 off = value - P;
3617           *(Elf64_Word *)P = (Elf64_Word)off;
3618           break;
3619       }
3620
3621       case R_X86_64_32:
3622           if (value >= 0x7fffffffL) {
3623 #if X86_64_ELF_NONPIC_HACK
3624               StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3625                                                 -> jumpIsland;
3626               value = pltAddress + A;
3627 #else
3628               barf("R_X86_64_32 relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3629                    symbol, value, oc->fileName );
3630 #endif
3631           }
3632           *(Elf64_Word *)P = (Elf64_Word)value;
3633           break;
3634
3635       case R_X86_64_32S:
3636           if ((StgInt64)value > 0x7fffffffL || (StgInt64)value < -0x80000000L) {
3637 #if X86_64_ELF_NONPIC_HACK
3638               StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3639                                                 -> jumpIsland;
3640               value = pltAddress + A;
3641 #else
3642               barf("R_X86_64_32S relocation out of range: %s = %p\nRecompile %s with -fPIC.",
3643                    symbol, value, oc->fileName );
3644 #endif
3645           }
3646           *(Elf64_Sword *)P = (Elf64_Sword)value;
3647           break;
3648
3649       case R_X86_64_GOTPCREL:
3650       {
3651           StgInt64 gotAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)->addr;
3652           StgInt64 off = gotAddress + A - P;
3653           *(Elf64_Word *)P = (Elf64_Word)off;
3654           break;
3655       }
3656
3657       case R_X86_64_PLT32:
3658       {
3659           StgInt64 off = value - P;
3660           if (off >= 0x7fffffffL || off < -0x80000000L) {
3661               StgInt64 pltAddress = (StgInt64) &makeSymbolExtra(oc, ELF_R_SYM(info), S)
3662                                                     -> jumpIsland;
3663               off = pltAddress + A - P;
3664           }
3665           *(Elf64_Word *)P = (Elf64_Word)off;
3666           break;
3667       }
3668 #endif
3669
3670          default:
3671             errorBelch("%s: unhandled ELF relocation(RelA) type %lu\n",
3672                   oc->fileName, (lnat)ELF_R_TYPE(info));
3673             return 0;
3674       }
3675
3676    }
3677    return 1;
3678 }
3679
3680 static int
3681 ocResolve_ELF ( ObjectCode* oc )
3682 {
3683    char *strtab;
3684    int   shnum, ok;
3685    Elf_Sym*  stab  = NULL;
3686    char*     ehdrC = (char*)(oc->image);
3687    Elf_Ehdr* ehdr  = (Elf_Ehdr*) ehdrC;
3688    Elf_Shdr* shdr  = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
3689
3690    /* first find "the" symbol table */
3691    stab = (Elf_Sym*) findElfSection ( ehdrC, SHT_SYMTAB );
3692
3693    /* also go find the string table */
3694    strtab = findElfSection ( ehdrC, SHT_STRTAB );
3695
3696    if (stab == NULL || strtab == NULL) {
3697       errorBelch("%s: can't find string or symbol table", oc->fileName);
3698       return 0;
3699    }
3700
3701    /* Process the relocation sections. */
3702    for (shnum = 0; shnum < ehdr->e_shnum; shnum++) {
3703       if (shdr[shnum].sh_type == SHT_REL) {
3704          ok = do_Elf_Rel_relocations ( oc, ehdrC, shdr,
3705                                        shnum, stab, strtab );
3706          if (!ok) return ok;
3707       }
3708       else
3709       if (shdr[shnum].sh_type == SHT_RELA) {
3710          ok = do_Elf_Rela_relocations ( oc, ehdrC, shdr,
3711                                         shnum, stab, strtab );
3712          if (!ok) return ok;
3713       }
3714    }
3715
3716 #if defined(powerpc_HOST_ARCH)
3717    ocFlushInstructionCache( oc );
3718 #endif
3719
3720    return 1;
3721 }
3722
3723 /*
3724  * IA64 specifics
3725  * Instructions are 41 bits long, packed into 128 bit bundles with a 5-bit template
3726  * at the front.  The following utility functions pack and unpack instructions, and
3727  * take care of the most common relocations.
3728  */
3729
3730 #ifdef ia64_HOST_ARCH
3731
3732 static Elf64_Xword
3733 ia64_extract_instruction(Elf64_Xword *target)
3734 {
3735    Elf64_Xword w1, w2;
3736    int slot = (Elf_Addr)target & 3;
3737    target = (Elf_Addr)target & ~3;
3738
3739    w1 = *target;
3740    w2 = *(target+1);
3741
3742    switch (slot)
3743    {
3744       case 0:
3745          return ((w1 >> 5) & 0x1ffffffffff);
3746       case 1:
3747          return (w1 >> 46) | ((w2 & 0x7fffff) << 18);
3748       case 2:
3749          return (w2 >> 23);
3750       default:
3751          barf("ia64_extract_instruction: invalid slot %p", target);
3752    }
3753 }
3754
3755 static void
3756 ia64_deposit_instruction(Elf64_Xword *target, Elf64_Xword value)
3757 {
3758    int slot = (Elf_Addr)target & 3;
3759    target = (Elf_Addr)target & ~3;
3760
3761    switch (slot)
3762    {
3763       case 0:
3764          *target |= value << 5;
3765          break;
3766       case 1:
3767          *target |= value << 46;
3768          *(target+1) |= value >> 18;
3769          break;
3770       case 2:
3771          *(target+1) |= value << 23;
3772          break;
3773    }
3774 }
3775
3776 static void
3777 ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value)
3778 {
3779    Elf64_Xword instruction;
3780    Elf64_Sxword rel_value;
3781
3782    rel_value = value - gp_val;
3783    if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff))
3784       barf("GP-relative data out of range (address = 0x%lx, gp = 0x%lx)", value, gp_val);
3785
3786    instruction = ia64_extract_instruction((Elf64_Xword *)target);
3787    instruction |= (((rel_value >> 0) & 0x07f) << 13)            /* imm7b */
3788                     | (((rel_value >> 7) & 0x1ff) << 27)        /* imm9d */
3789                     | (((rel_value >> 16) & 0x01f) << 22)       /* imm5c */
3790                     | ((Elf64_Xword)(rel_value < 0) << 36);     /* s */
3791    ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3792 }
3793
3794 static void
3795 ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc)
3796 {
3797    Elf64_Xword instruction;
3798    Elf64_Sxword rel_value;
3799    Elf_Addr entry;
3800
3801    entry = allocatePLTEntry(value, oc);
3802
3803    rel_value = (entry >> 4) - (target >> 4);
3804    if ((rel_value > 0xfffff) || (rel_value < -0xfffff))
3805       barf("PLT entry too far away (entry = 0x%lx, target = 0x%lx)", entry, target);
3806
3807    instruction = ia64_extract_instruction((Elf64_Xword *)target);
3808    instruction |= ((rel_value & 0xfffff) << 13)                 /* imm20b */
3809                     | ((Elf64_Xword)(rel_value < 0) << 36);     /* s */
3810    ia64_deposit_instruction((Elf64_Xword *)target, instruction);
3811 }
3812
3813 #endif /* ia64 */
3814
3815 /*
3816  * PowerPC & X86_64 ELF specifics
3817  */
3818
3819 #if defined(powerpc_HOST_ARCH) || defined(x86_64_HOST_ARCH)
3820
3821 static int ocAllocateSymbolExtras_ELF( ObjectCode *oc )
3822 {
3823   Elf_Ehdr *ehdr;
3824   Elf_Shdr* shdr;
3825   int i;
3826
3827   ehdr = (Elf_Ehdr *) oc->image;
3828   shdr = (Elf_Shdr *) ( ((char *)oc->image) + ehdr->e_shoff );
3829
3830   for( i = 0; i < ehdr->e_shnum; i++ )
3831     if( shdr[i].sh_type == SHT_SYMTAB )
3832       break;
3833
3834   if( i == ehdr->e_shnum )
3835   {
3836     errorBelch( "This ELF file contains no symtab" );
3837     return 0;
3838   }
3839
3840   if( shdr[i].sh_entsize != sizeof( Elf_Sym ) )
3841   {
3842     errorBelch( "The entry size (%d) of the symtab isn't %d\n",
3843       (int) shdr[i].sh_entsize, (int) sizeof( Elf_Sym ) );
3844
3845     return 0;
3846   }
3847
3848   return ocAllocateSymbolExtras( oc, shdr[i].sh_size / sizeof( Elf_Sym ), 0 );
3849 }
3850
3851 #endif /* powerpc */
3852
3853 #endif /* ELF */
3854
3855 /* --------------------------------------------------------------------------
3856  * Mach-O specifics
3857  * ------------------------------------------------------------------------*/
3858
3859 #if defined(OBJFORMAT_MACHO)
3860
3861 /*
3862   Support for MachO linking on Darwin/MacOS X
3863   by Wolfgang Thaller (wolfgang.thaller@gmx.net)
3864
3865   I hereby formally apologize for the hackish nature of this code.
3866   Things that need to be done:
3867   *) implement ocVerifyImage_MachO
3868   *) add still more sanity checks.
3869 */
3870
3871 #if x86_64_HOST_ARCH || powerpc64_HOST_ARCH
3872 #define mach_header mach_header_64
3873 #define segment_command segment_command_64
3874 #define section section_64
3875 #define nlist nlist_64
3876 #endif
3877
3878 #ifdef powerpc_HOST_ARCH
3879 static int ocAllocateSymbolExtras_MachO(ObjectCode* oc)
3880 {
3881     struct mach_header *header = (struct mach_header *) oc->image;
3882     struct load_command *lc = (struct load_command *) (header + 1);
3883     unsigned i;
3884
3885     for( i = 0; i < header->ncmds; i++ )
3886     {
3887         if( lc->cmd == LC_SYMTAB )
3888         {
3889                 // Find out the first and last undefined external
3890                 // symbol, so we don't have to allocate too many
3891                 // jump islands.
3892             struct symtab_command *symLC = (struct symtab_command *) lc;
3893             unsigned min = symLC->nsyms, max = 0;
3894             struct nlist *nlist =
3895                 symLC ? (struct nlist*) ((char*) oc->image + symLC->symoff)
3896                       : NULL;
3897             for(i=0;i<symLC->nsyms;i++)
3898             {
3899                 if(nlist[i].n_type & N_STAB)
3900                     ;
3901                 else if(nlist[i].n_type & N_EXT)
3902                 {
3903                     if((nlist[i].n_type & N_TYPE) == N_UNDF
3904                         && (nlist[i].n_value == 0))
3905                     {
3906                         if(i < min)
3907                             min = i;
3908                         if(i > max)
3909                             max = i;
3910                     }
3911                 }
3912             }
3913             if(max >= min)
3914                 return ocAllocateSymbolExtras(oc, max - min + 1, min);
3915
3916             break;
3917         }
3918
3919         lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
3920     }
3921     return ocAllocateSymbolExtras(oc,0,0);
3922 }
3923 #endif
3924 #ifdef x86_64_HOST_ARCH
3925 static int ocAllocateSymbolExtras_MachO(ObjectCode* oc)
3926 {
3927     struct mach_header *header = (struct mach_header *) oc->image;
3928     struct load_command *lc = (struct load_command *) (header + 1);
3929     unsigned i;
3930
3931     for( i = 0; i < header->ncmds; i++ )
3932     {
3933         if( lc->cmd == LC_SYMTAB )
3934         {
3935                 // Just allocate one entry for every symbol
3936             struct symtab_command *symLC = (struct symtab_command *) lc;
3937
3938             return ocAllocateSymbolExtras(oc, symLC->nsyms, 0);
3939         }
3940
3941         lc = (struct load_command *) ( ((char *)lc) + lc->cmdsize );
3942     }
3943     return ocAllocateSymbolExtras(oc,0,0);
3944 }
3945 #endif
3946
3947 static int ocVerifyImage_MachO(ObjectCode* oc)
3948 {
3949     char *image = (char*) oc->image;
3950     struct mach_header *header = (struct mach_header*) image;
3951
3952 #if x86_64_TARGET_ARCH || powerpc64_TARGET_ARCH
3953     if(header->magic != MH_MAGIC_64)
3954         return 0;
3955 #else
3956     if(header->magic != MH_MAGIC)
3957         return 0;
3958 #endif
3959     // FIXME: do some more verifying here
3960     return 1;
3961 }
3962
3963 static int resolveImports(
3964     ObjectCode* oc,
3965     char *image,
3966     struct symtab_command *symLC,
3967     struct section *sect,    // ptr to lazy or non-lazy symbol pointer section
3968     unsigned long *indirectSyms,
3969     struct nlist *nlist)
3970 {
3971     unsigned i;
3972     size_t itemSize = 4;
3973
3974 #if i386_HOST_ARCH
3975     int isJumpTable = 0;
3976     if(!strcmp(sect->sectname,"__jump_table"))
3977     {
3978         isJumpTable = 1;
3979         itemSize = 5;
3980         ASSERT(sect->reserved2 == itemSize);
3981     }
3982 #endif
3983
3984     for(i=0; i*itemSize < sect->size;i++)
3985     {
3986         // according to otool, reserved1 contains the first index into the indirect symbol table
3987         struct nlist *symbol = &nlist[indirectSyms[sect->reserved1+i]];
3988         char *nm = image + symLC->stroff + symbol->n_un.n_strx;
3989         void *addr = NULL;
3990
3991         if((symbol->n_type & N_TYPE) == N_UNDF
3992             && (symbol->n_type & N_EXT) && (symbol->n_value != 0))
3993             addr = (void*) (symbol->n_value);
3994         else
3995             addr = lookupSymbol(nm);
3996         if(!addr)
3997         {
3998             errorBelch("\n%s: unknown symbol `%s'", oc->fileName, nm);
3999             return 0;
4000         }
4001         ASSERT(addr);
4002
4003 #if i386_HOST_ARCH
4004         if(isJumpTable)
4005         {
4006             checkProddableBlock(oc,image + sect->offset + i*itemSize);
4007             *(image + sect->offset + i*itemSize) = 0xe9; // jmp
4008             *(unsigned*)(image + sect->offset + i*itemSize + 1)
4009                 = (char*)addr - (image + sect->offset + i*itemSize + 5);
4010         }
4011         else
4012 #endif
4013         {
4014             checkProddableBlock(oc,((void**)(image + sect->offset)) + i);
4015             ((void**)(image + sect->offset))[i] = addr;
4016         }
4017     }
4018
4019     return 1;
4020 }
4021
4022 static unsigned long relocateAddress(
4023     ObjectCode* oc,
4024     int nSections,
4025     struct section* sections,
4026     unsigned long address)
4027 {
4028     int i;
4029     for(i = 0; i < nSections; i++)
4030     {
4031         if(sections[i].addr <= address
4032             && address < sections[i].addr + sections[i].size)
4033         {
4034             return (unsigned long)oc->image
4035                     + sections[i].offset + address - sections[i].addr;
4036         }
4037     }
4038     barf("Invalid Mach-O file:"
4039          "Address out of bounds while relocating object file");
4040     return 0;
4041 }
4042
4043 static int relocateSection(
4044     ObjectCode* oc,
4045     char *image,
4046     struct symtab_command *symLC, struct nlist *nlist,
4047     int nSections, struct section* sections, struct section *sect)
4048 {
4049     struct relocation_info *relocs;
4050     int i,n;
4051
4052     if(!strcmp(sect->sectname,"__la_symbol_ptr"))
4053         return 1;
4054     else if(!strcmp(sect->sectname,"__nl_symbol_ptr"))
4055         return 1;
4056     else if(!strcmp(sect->sectname,"__la_sym_ptr2"))
4057         return 1;
4058     else if(!strcmp(sect->sectname,"__la_sym_ptr3"))
4059         return 1;
4060
4061     n = sect->nreloc;
4062     relocs = (struct relocation_info*) (image + sect->reloff);
4063
4064     for(i=0;i<n;i++)
4065     {
4066 #ifdef x86_64_HOST_ARCH
4067         struct relocation_info *reloc = &relocs[i];
4068
4069         char    *thingPtr = image + sect->offset + reloc->r_address;
4070         uint64_t thing;
4071         /* We shouldn't need to initialise this, but gcc on OS X 64 bit
4072            complains that it may be used uninitialized if we don't */
4073         uint64_t value = 0;
4074         uint64_t baseValue;
4075         int type = reloc->r_type;
4076
4077         checkProddableBlock(oc,thingPtr);
4078         switch(reloc->r_length)
4079         {
4080             case 0:
4081                 thing = *(uint8_t*)thingPtr;
4082                 baseValue = (uint64_t)thingPtr + 1;
4083                 break;
4084             case 1:
4085                 thing = *(uint16_t*)thingPtr;
4086                 baseValue = (uint64_t)thingPtr + 2;
4087                 break;
4088             case 2:
4089                 thing = *(uint32_t*)thingPtr;
4090                 baseValue = (uint64_t)thingPtr + 4;
4091                 break;
4092             case 3:
4093                 thing = *(uint64_t*)thingPtr;
4094                 baseValue = (uint64_t)thingPtr + 8;
4095                 break;
4096             default:
4097                 barf("Unknown size.");
4098         }
4099
4100         if(type == X86_64_RELOC_GOT
4101            || type == X86_64_RELOC_GOT_LOAD)
4102         {
4103             ASSERT(reloc->r_extern);
4104             value = (uint64_t) &makeSymbolExtra(oc, reloc->r_symbolnum, value)->addr;
4105
4106             type = X86_64_RELOC_SIGNED;
4107         }
4108         else if(reloc->r_extern)
4109         {
4110             struct nlist *symbol = &nlist[reloc->r_symbolnum];
4111             char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4112             if(symbol->n_value == 0)
4113                 value = (uint64_t) lookupSymbol(nm);
4114             else
4115                 value = relocateAddress(oc, nSections, sections,
4116                                         symbol->n_value);
4117         }
4118         else
4119         {
4120             value = sections[reloc->r_symbolnum-1].offset
4121                   - sections[reloc->r_symbolnum-1].addr
4122                   + (uint64_t) image;
4123         }
4124
4125         if(type == X86_64_RELOC_BRANCH)
4126         {
4127             if((int32_t)(value - baseValue) != (int64_t)(value - baseValue))
4128             {
4129                 ASSERT(reloc->r_extern);
4130                 value = (uint64_t) &makeSymbolExtra(oc, reloc->r_symbolnum, value)
4131                                         -> jumpIsland;
4132             }
4133             ASSERT((int32_t)(value - baseValue) == (int64_t)(value - baseValue));
4134             type = X86_64_RELOC_SIGNED;
4135         }
4136
4137         switch(type)
4138         {
4139             case X86_64_RELOC_UNSIGNED:
4140                 ASSERT(!reloc->r_pcrel);
4141                 thing += value;
4142                 break;
4143             case X86_64_RELOC_SIGNED:
4144                 ASSERT(reloc->r_pcrel);
4145                 thing += value - baseValue;
4146                 break;
4147             case X86_64_RELOC_SUBTRACTOR:
4148                 ASSERT(!reloc->r_pcrel);
4149                 thing -= value;
4150                 break;
4151             default:
4152                 barf("unkown relocation");
4153         }
4154
4155         switch(reloc->r_length)
4156         {
4157             case 0:
4158                 *(uint8_t*)thingPtr = thing;
4159                 break;
4160             case 1:
4161                 *(uint16_t*)thingPtr = thing;
4162                 break;
4163             case 2:
4164                 *(uint32_t*)thingPtr = thing;
4165                 break;
4166             case 3:
4167                 *(uint64_t*)thingPtr = thing;
4168                 break;
4169         }
4170 #else
4171         if(relocs[i].r_address & R_SCATTERED)
4172         {
4173             struct scattered_relocation_info *scat =
4174                 (struct scattered_relocation_info*) &relocs[i];
4175
4176             if(!scat->r_pcrel)
4177             {
4178                 if(scat->r_length == 2)
4179                 {
4180                     unsigned long word = 0;
4181                     unsigned long* wordPtr = (unsigned long*) (image + sect->offset + scat->r_address);
4182                     checkProddableBlock(oc,wordPtr);
4183
4184                     // Note on relocation types:
4185                     // i386 uses the GENERIC_RELOC_* types,
4186                     // while ppc uses special PPC_RELOC_* types.
4187                     // *_RELOC_VANILLA and *_RELOC_PAIR have the same value
4188                     // in both cases, all others are different.
4189                     // Therefore, we use GENERIC_RELOC_VANILLA
4190                     // and GENERIC_RELOC_PAIR instead of the PPC variants,
4191                     // and use #ifdefs for the other types.
4192
4193                     // Step 1: Figure out what the relocated value should be
4194                     if(scat->r_type == GENERIC_RELOC_VANILLA)
4195                     {
4196                         word = *wordPtr + (unsigned long) relocateAddress(
4197                                                                 oc,
4198                                                                 nSections,
4199                                                                 sections,
4200                                                                 scat->r_value)
4201                                         - scat->r_value;
4202                     }
4203 #ifdef powerpc_HOST_ARCH
4204                     else if(scat->r_type == PPC_RELOC_SECTDIFF
4205                         || scat->r_type == PPC_RELOC_LO16_SECTDIFF
4206                         || scat->r_type == PPC_RELOC_HI16_SECTDIFF
4207                         || scat->r_type == PPC_RELOC_HA16_SECTDIFF)
4208 #else
4209                     else if(scat->r_type == GENERIC_RELOC_SECTDIFF)
4210 #endif
4211                     {
4212                         struct scattered_relocation_info *pair =
4213                                 (struct scattered_relocation_info*) &relocs[i+1];
4214
4215                         if(!pair->r_scattered || pair->r_type != GENERIC_RELOC_PAIR)
4216                             barf("Invalid Mach-O file: "
4217                                  "RELOC_*_SECTDIFF not followed by RELOC_PAIR");
4218
4219                         word = (unsigned long)
4220                                (relocateAddress(oc, nSections, sections, scat->r_value)
4221                               - relocateAddress(oc, nSections, sections, pair->r_value));
4222                         i++;
4223                     }
4224 #ifdef powerpc_HOST_ARCH
4225                     else if(scat->r_type == PPC_RELOC_HI16
4226                          || scat->r_type == PPC_RELOC_LO16
4227                          || scat->r_type == PPC_RELOC_HA16
4228                          || scat->r_type == PPC_RELOC_LO14)
4229                     {   // these are generated by label+offset things
4230                         struct relocation_info *pair = &relocs[i+1];
4231                         if((pair->r_address & R_SCATTERED) || pair->r_type != PPC_RELOC_PAIR)
4232                             barf("Invalid Mach-O file: "
4233                                  "PPC_RELOC_* not followed by PPC_RELOC_PAIR");
4234
4235                         if(scat->r_type == PPC_RELOC_LO16)
4236                         {
4237                             word = ((unsigned short*) wordPtr)[1];
4238                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4239                         }
4240                         else if(scat->r_type == PPC_RELOC_LO14)
4241                         {
4242                             barf("Unsupported Relocation: PPC_RELOC_LO14");
4243                             word = ((unsigned short*) wordPtr)[1] & 0xFFFC;
4244                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4245                         }
4246                         else if(scat->r_type == PPC_RELOC_HI16)
4247                         {
4248                             word = ((unsigned short*) wordPtr)[1] << 16;
4249                             word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
4250                         }
4251                         else if(scat->r_type == PPC_RELOC_HA16)
4252                         {
4253                             word = ((unsigned short*) wordPtr)[1] << 16;
4254                             word += ((short)relocs[i+1].r_address & (short)0xFFFF);
4255                         }
4256
4257
4258                         word += (unsigned long) relocateAddress(oc, nSections, sections, scat->r_value)
4259                                                 - scat->r_value;
4260
4261                         i++;
4262                     }
4263  #endif
4264                     else
4265                         continue;  // ignore the others
4266
4267 #ifdef powerpc_HOST_ARCH
4268                     if(scat->r_type == GENERIC_RELOC_VANILLA
4269                         || scat->r_type == PPC_RELOC_SECTDIFF)
4270 #else
4271                     if(scat->r_type == GENERIC_RELOC_VANILLA
4272                         || scat->r_type == GENERIC_RELOC_SECTDIFF)
4273 #endif
4274                     {
4275                         *wordPtr = word;
4276                     }
4277 #ifdef powerpc_HOST_ARCH
4278                     else if(scat->r_type == PPC_RELOC_LO16_SECTDIFF || scat->r_type == PPC_RELOC_LO16)
4279                     {
4280                         ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
4281                     }
4282                     else if(scat->r_type == PPC_RELOC_HI16_SECTDIFF || scat->r_type == PPC_RELOC_HI16)
4283                     {
4284                         ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
4285                     }
4286                     else if(scat->r_type == PPC_RELOC_HA16_SECTDIFF || scat->r_type == PPC_RELOC_HA16)
4287                     {
4288                         ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
4289                             + ((word & (1<<15)) ? 1 : 0);
4290                     }
4291 #endif
4292                 }
4293             }
4294
4295             continue; // FIXME: I hope it's OK to ignore all the others.
4296         }
4297         else
4298         {
4299             struct relocation_info *reloc = &relocs[i];
4300             if(reloc->r_pcrel && !reloc->r_extern)
4301                 continue;
4302
4303             if(reloc->r_length == 2)
4304             {
4305                 unsigned long word = 0;
4306 #ifdef powerpc_HOST_ARCH
4307                 unsigned long jumpIsland = 0;
4308                 long offsetToJumpIsland = 0xBADBAD42; // initialise to bad value
4309                                                       // to avoid warning and to catch
4310                                                       // bugs.
4311 #endif
4312
4313                 unsigned long* wordPtr = (unsigned long*) (image + sect->offset + reloc->r_address);
4314                 checkProddableBlock(oc,wordPtr);
4315
4316                 if(reloc->r_type == GENERIC_RELOC_VANILLA)
4317                 {
4318                     word = *wordPtr;
4319                 }
4320 #ifdef powerpc_HOST_ARCH
4321                 else if(reloc->r_type == PPC_RELOC_LO16)
4322                 {
4323                     word = ((unsigned short*) wordPtr)[1];
4324                     word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
4325                 }
4326                 else if(reloc->r_type == PPC_RELOC_HI16)
4327                 {
4328                     word = ((unsigned short*) wordPtr)[1] << 16;
4329                     word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
4330                 }
4331                 else if(reloc->r_type == PPC_RELOC_HA16)
4332                 {
4333                     word = ((unsigned short*) wordPtr)[1] << 16;
4334                     word += ((short)relocs[i+1].r_address & (short)0xFFFF);
4335                 }
4336                 else if(reloc->r_type == PPC_RELOC_BR24)
4337                 {
4338                     word = *wordPtr;
4339                     word = (word & 0x03FFFFFC) | ((word & 0x02000000) ? 0xFC000000 : 0);
4340                 }
4341 #endif
4342
4343                 if(!reloc->r_extern)
4344                 {
4345                     long delta =
4346                         sections[reloc->r_symbolnum-1].offset
4347                         - sections[reloc->r_symbolnum-1].addr
4348                         + ((long) image);
4349
4350                     word += delta;
4351                 }
4352                 else
4353                 {
4354                     struct nlist *symbol = &nlist[reloc->r_symbolnum];
4355                     char *nm = image + symLC->stroff + symbol->n_un.n_strx;
4356                     void *symbolAddress = lookupSymbol(nm);
4357                     if(!symbolAddress)
4358                     {
4359                         errorBelch("\nunknown symbol `%s'", nm);
4360                         return 0;
4361                     }
4362
4363                     if(reloc->r_pcrel)
4364                     {
4365 #ifdef powerpc_HOST_ARCH
4366                             // In the .o file, this should be a relative jump to NULL
4367                             // and we'll change it to a relative jump to the symbol
4368                         ASSERT(word + reloc->r_address == 0);
4369                         jumpIsland = (unsigned long)
4370                                         &makeSymbolExtra(oc,
4371                                                          reloc->r_symbolnum,
4372                                                          (unsigned long) symbolAddress)
4373                                          -> jumpIsland;
4374                         if(jumpIsland != 0)
4375                         {
4376                             offsetToJumpIsland = word + jumpIsland
4377                                 - (((long)image) + sect->offset - sect->addr);
4378                         }
4379 #endif
4380                         word += (unsigned long) symbolAddress
4381                                 - (((long)image) + sect->offset - sect->addr);
4382                     }
4383                     else
4384                     {
4385                         word += (unsigned long) symbolAddress;
4386                     }
4387                 }
4388
4389                 if(reloc->r_type == GENERIC_RELOC_VANILLA)
4390                 {
4391                     *wordPtr = word;
4392                     continue;
4393                 }
4394 #ifdef powerpc_HOST_ARCH
4395                 else if(reloc->r_type == PPC_RELOC_LO16)
4396                 {
4397                     ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
4398                     i++; continue;
4399                 }
4400                 else if(reloc->r_type == PPC_RELOC_HI16)
4401                 {
4402                     ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
4403                     i++; continue;
4404                 }
4405                 else if(reloc->r_type == PPC_RELOC_HA16)
4406                 {
4407                     ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
4408                         + ((word & (1<<15)) ? 1 : 0);
4409                     i++; continue;
4410                 }
4411                 else if(reloc->r_type == PPC_RELOC_BR24)
4412                 {
4413                     if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
4414                     {
4415                         // The branch offset is too large.
4416                         // Therefore, we try to use a jump island.
4417                         if(jumpIsland == 0)
4418                         {
4419                             barf("unconditional relative branch out of range: "
4420                                  "no jump island available");
4421                         }
4422
4423                         word = offsetToJumpIsland;
4424                         if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
4425                             barf("unconditional relative branch out of range: "
4426                                  "jump island out of range");
4427                     }
4428                     *wordPtr = (*wordPtr & 0xFC000003) | (word & 0x03FFFFFC);
4429                     continue;
4430                 }
4431 #endif
4432             }
4433             barf("\nunknown relocation %d",reloc->r_type);
4434             return 0;
4435         }
4436 #endif
4437     }
4438     return 1;
4439 }
4440
4441 static int ocGetNames_MachO(ObjectCode* oc)
4442 {
4443     char *image = (char*) oc->image;
4444     struct mach_header *header = (struct mach_header*) image;
4445     struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
4446     unsigned i,curSymbol = 0;
4447     struct segment_command *segLC = NULL;
4448     struct section *sections;
4449     struct symtab_command *symLC = NULL;
4450     struct nlist *nlist;
4451     unsigned long commonSize = 0;
4452     char    *commonStorage = NULL;
4453     unsigned long commonCounter;
4454
4455     for(i=0;i<header->ncmds;i++)
4456     {
4457         if(lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64)
4458             segLC = (struct segment_command*) lc;
4459         else if(lc->cmd == LC_SYMTAB)
4460             symLC = (struct symtab_command*) lc;
4461         lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
4462     }
4463
4464     sections = (struct section*) (segLC+1);
4465     nlist = symLC ? (struct nlist*) (image + symLC->symoff)
4466                   : NULL;
4467
4468     if(!segLC)
4469         barf("ocGetNames_MachO: no segment load command");
4470
4471     for(i=0;i<segLC->nsects;i++)
4472     {
4473         if(sections[i].size == 0)
4474             continue;
4475
4476         if((sections[i].flags & SECTION_TYPE) == S_ZEROFILL)
4477         {
4478             char * zeroFillArea = stgCallocBytes(1,sections[i].size,
4479                                       "ocGetNames_MachO(common symbols)");
4480             sections[i].offset = zeroFillArea - image;
4481         }
4482
4483         if(!strcmp(sections[i].sectname,"__text"))
4484             addSection(oc, SECTIONKIND_CODE_OR_RODATA,
4485                 (void*) (image + sections[i].offset),
4486                 (void*) (image + sections[i].offset + sections[i].size));
4487         else if(!strcmp(sections[i].sectname,"__const"))
4488             addSection(oc, SECTIONKIND_RWDATA,
4489                 (void*) (image + sections[i].offset),
4490                 (void*) (image + sections[i].offset + sections[i].size));
4491         else if(!strcmp(sections[i].sectname,"__data"))
4492             addSection(oc, SECTIONKIND_RWDATA,
4493                 (void*) (image + sections[i].offset),
4494                 (void*) (image + sections[i].offset + sections[i].size));
4495         else if(!strcmp(sections[i].sectname,"__bss")
4496                 || !strcmp(sections[i].sectname,"__common"))
4497             addSection(oc, SECTIONKIND_RWDATA,
4498                 (void*) (image + sections[i].offset),
4499                 (void*) (image + sections[i].offset + sections[i].size));
4500
4501         addProddableBlock(oc, (void*) (image + sections[i].offset),
4502                                         sections[i].size);
4503     }
4504
4505         // count external symbols defined here
4506     oc->n_symbols = 0;
4507     if(symLC)
4508     {
4509         for(i=0;i<symLC->nsyms;i++)
4510         {
4511             if(nlist[i].n_type & N_STAB)
4512                 ;
4513             else if(nlist[i].n_type & N_EXT)
4514             {
4515                 if((nlist[i].n_type & N_TYPE) == N_UNDF
4516                     && (nlist[i].n_value != 0))
4517                 {
4518                     commonSize += nlist[i].n_value;
4519                     oc->n_symbols++;
4520                 }
4521                 else if((nlist[i].n_type & N_TYPE) == N_SECT)
4522                     oc->n_symbols++;
4523             }
4524         }
4525     }
4526     oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
4527                                    "ocGetNames_MachO(oc->symbols)");
4528
4529     if(symLC)
4530     {
4531         for(i=0;i<symLC->nsyms;i++)
4532         {
4533             if(nlist[i].n_type & N_STAB)
4534                 ;
4535             else if((nlist[i].n_type & N_TYPE) == N_SECT)
4536             {
4537                 if(nlist[i].n_type & N_EXT)
4538                 {
4539                     char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4540                     if((nlist[i].n_desc & N_WEAK_DEF) && lookupSymbol(nm))
4541                         ; // weak definition, and we already have a definition
4542                     else
4543                     {
4544                             ghciInsertStrHashTable(oc->fileName, symhash, nm,
4545                                                     image
4546                                                     + sections[nlist[i].n_sect-1].offset
4547                                                     - sections[nlist[i].n_sect-1].addr
4548                                                     + nlist[i].n_value);
4549                             oc->symbols[curSymbol++] = nm;
4550                     }
4551                 }
4552             }
4553         }
4554     }
4555
4556     commonStorage = stgCallocBytes(1,commonSize,"ocGetNames_MachO(common symbols)");
4557     commonCounter = (unsigned long)commonStorage;
4558     if(symLC)
4559     {
4560         for(i=0;i<symLC->nsyms;i++)
4561         {
4562             if((nlist[i].n_type & N_TYPE) == N_UNDF
4563                     && (nlist[i].n_type & N_EXT) && (nlist[i].n_value != 0))
4564             {
4565                 char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
4566                 unsigned long sz = nlist[i].n_value;
4567
4568                 nlist[i].n_value = commonCounter;
4569
4570                 ghciInsertStrHashTable(oc->fileName, symhash, nm,
4571                                        (void*)commonCounter);
4572                 oc->symbols[curSymbol++] = nm;
4573
4574                 commonCounter += sz;
4575             }
4576         }
4577     }
4578     return 1;
4579 }
4580
4581 static int ocResolve_MachO(ObjectCode* oc)
4582 {
4583     char *image = (char*) oc->image;
4584     struct mach_header *header = (struct mach_header*) image;
4585     struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
4586     unsigned i;
4587     struct segment_command *segLC = NULL;
4588     struct section *sections;
4589     struct symtab_command *symLC = NULL;
4590     struct dysymtab_command *dsymLC = NULL;
4591     struct nlist *nlist;
4592
4593     for(i=0;i<header->ncmds;i++)
4594     {
4595         if(lc->cmd == LC_SEGMENT || lc->cmd == LC_SEGMENT_64)
4596             segLC = (struct segment_command*) lc;
4597         else if(lc->cmd == LC_SYMTAB)
4598             symLC = (struct symtab_command*) lc;
4599         else if(lc->cmd == LC_DYSYMTAB)
4600             dsymLC = (struct dysymtab_command*) lc;
4601         lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
4602     }
4603
4604     sections = (struct section*) (segLC+1);
4605     nlist = symLC ? (struct nlist*) (image + symLC->symoff)
4606                   : NULL;
4607
4608     if(dsymLC)
4609     {
4610         unsigned long *indirectSyms
4611             = (unsigned long*) (image + dsymLC->indirectsymoff);
4612
4613         for(i=0;i<segLC->nsects;i++)
4614         {
4615             if(    !strcmp(sections[i].sectname,"__la_symbol_ptr")
4616                 || !strcmp(sections[i].sectname,"__la_sym_ptr2")
4617                 || !strcmp(sections[i].sectname,"__la_sym_ptr3"))
4618             {
4619                 if(!resolveImports(oc,image,symLC,&sections[i],indirectSyms,nlist))
4620                     return 0;
4621             }
4622             else if(!strcmp(sections[i].sectname,"__nl_symbol_ptr")
4623                 ||  !strcmp(sections[i].sectname,"__pointers"))
4624             {
4625                 if(!resolveImports(oc,image,symLC,&sections[i],indirectSyms,nlist))
4626                     return 0;
4627             }
4628             else if(!strcmp(sections[i].sectname,"__jump_table"))
4629             {
4630                 if(!resolveImports(oc,image,symLC,&sections[i],indirectSyms,nlist))
4631                     return 0;
4632             }
4633         }
4634     }
4635
4636     for(i=0;i<segLC->nsects;i++)
4637     {
4638         if(!relocateSection(oc,image,symLC,nlist,segLC->nsects,sections,&sections[i]))
4639             return 0;
4640     }
4641
4642 #if defined (powerpc_HOST_ARCH)
4643     ocFlushInstructionCache( oc );
4644 #endif
4645
4646     return 1;
4647 }
4648
4649 #ifdef powerpc_HOST_ARCH
4650 /*
4651  * The Mach-O object format uses leading underscores. But not everywhere.
4652  * There is a small number of runtime support functions defined in
4653  * libcc_dynamic.a whose name does not have a leading underscore.
4654  * As a consequence, we can't get their address from C code.
4655  * We have to use inline assembler just to take the address of a function.
4656  * Yuck.
4657  */
4658
4659 static void machoInitSymbolsWithoutUnderscore()
4660 {
4661     extern void* symbolsWithoutUnderscore[];
4662     void **p = symbolsWithoutUnderscore;
4663     __asm__ volatile(".globl _symbolsWithoutUnderscore\n.data\n_symbolsWithoutUnderscore:");
4664
4665 #undef SymI_NeedsProto
4666 #define SymI_NeedsProto(x)  \
4667     __asm__ volatile(".long " # x);
4668
4669     RTS_MACHO_NOUNDERLINE_SYMBOLS
4670
4671     __asm__ volatile(".text");
4672
4673 #undef SymI_NeedsProto
4674 #define SymI_NeedsProto(x)  \
4675     ghciInsertStrHashTable("(GHCi built-in symbols)", symhash, #x, *p++);
4676
4677     RTS_MACHO_NOUNDERLINE_SYMBOLS
4678
4679 #undef SymI_NeedsProto
4680 }
4681 #endif
4682
4683 /*
4684  * Figure out by how much to shift the entire Mach-O file in memory
4685  * when loading so that its single segment ends up 16-byte-aligned
4686  */
4687 static int machoGetMisalignment( FILE * f )
4688 {
4689     struct mach_header header;
4690     int misalignment;
4691
4692     fread(&header, sizeof(header), 1, f);
4693     rewind(f);
4694
4695 #if x86_64_TARGET_ARCH || powerpc64_TARGET_ARCH
4696     if(header.magic != MH_MAGIC_64)
4697         return 0;
4698 #else
4699     if(header.magic != MH_MAGIC)
4700         return 0;
4701 #endif
4702
4703     misalignment = (header.sizeofcmds + sizeof(header))
4704                     & 0xF;
4705
4706     return misalignment ? (16 - misalignment) : 0;
4707 }
4708
4709 #endif
4710