[project @ 2003-12-17 17:18:27 by sof]
[ghc-hetmet.git] / ghc / rts / Linker.c
index 388913d..85d5809 100644 (file)
@@ -1,12 +1,14 @@
 /* -----------------------------------------------------------------------------
- * $Id: Linker.c,v 1.48 2001/06/29 14:47:58 sewardj Exp $
  *
- * (c) The GHC Team, 2000
+ * (c) The GHC Team, 2000-2003
  *
  * RTS Object Linker
  *
  * ---------------------------------------------------------------------------*/
 
+#if 0
+#include "PosixSource.h"
+#endif
 #include "Rts.h"
 #include "RtsFlags.h"
 #include "HsFFI.h"
 #include "LinkerInternals.h"
 #include "RtsUtils.h"
 #include "StoragePriv.h"
+#include "Schedule.h"
 
 #ifdef HAVE_SYS_TYPES_H
 #include <sys/types.h>
 #endif
 
+#include <stdlib.h>
+#include <string.h>
+
 #ifdef HAVE_SYS_STAT_H
 #include <sys/stat.h>
 #endif
 
-#ifdef HAVE_DLFCN_H
+#if defined(HAVE_FRAMEWORK_HASKELLSUPPORT)
+#include <HaskellSupport/dlfcn.h>
+#elif defined(HAVE_DLFCN_H)
 #include <dlfcn.h>
 #endif
 
-#if defined(linux_TARGET_OS) || defined(solaris2_TARGET_OS) || defined(freebsd_TARGET_OS)
+#if defined(cygwin32_TARGET_OS)
+#ifdef HAVE_DIRENT_H
+#include <dirent.h>
+#endif
+
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+#include <regex.h>
+#include <sys/fcntl.h>
+#include <sys/termios.h>
+#include <sys/utime.h>
+#include <sys/utsname.h>
+#include <sys/wait.h>
+#endif
+
+#if defined(ia64_TARGET_ARCH)
+#define USE_MMAP
+#include <fcntl.h>
+#include <sys/mman.h>
+#endif
+
+#if defined(linux_TARGET_OS) || defined(solaris2_TARGET_OS) || defined(freebsd_TARGET_OS) || defined(netbsd_TARGET_OS) || defined(openbsd_TARGET_OS)
 #  define OBJFORMAT_ELF
 #elif defined(cygwin32_TARGET_OS) || defined (mingw32_TARGET_OS)
 #  define OBJFORMAT_PEi386
 #  include <windows.h>
+#  include <math.h>
+#elif defined(darwin_TARGET_OS)
+#  include <mach-o/ppc/reloc.h>
+#  define OBJFORMAT_MACHO
+#  include <mach-o/loader.h>
+#  include <mach-o/nlist.h>
+#  include <mach-o/reloc.h>
+#  include <mach-o/dyld.h>
 #endif
 
 /* Hash table mapping symbol names to Symbol */
-/*Str*/HashTable *symhash;
+static /*Str*/HashTable *symhash;
+
+/* List of currently loaded objects */
+ObjectCode *objects = NULL;    /* initially empty */
 
 #if defined(OBJFORMAT_ELF)
 static int ocVerifyImage_ELF    ( ObjectCode* oc );
@@ -46,6 +87,13 @@ static int ocResolve_ELF        ( ObjectCode* oc );
 static int ocVerifyImage_PEi386 ( ObjectCode* oc );
 static int ocGetNames_PEi386    ( ObjectCode* oc );
 static int ocResolve_PEi386     ( ObjectCode* oc );
+#elif defined(OBJFORMAT_MACHO)
+static int ocAllocateJumpIslands_MachO ( ObjectCode* oc );
+static int ocVerifyImage_MachO    ( ObjectCode* oc );
+static int ocGetNames_MachO       ( ObjectCode* oc );
+static int ocResolve_MachO        ( ObjectCode* oc );
+
+static void machoInitSymbolsWithoutUnderscore( void );
 #endif
 
 /* -----------------------------------------------------------------------------
@@ -71,19 +119,117 @@ typedef struct _RtsSymbolVal {
 #endif
 
 #if !defined (mingw32_TARGET_OS)
-
 #define RTS_POSIX_ONLY_SYMBOLS                  \
       SymX(stg_sig_install)                    \
       Sym(nocldstop)
-#define RTS_MINGW_ONLY_SYMBOLS /**/
+#endif
 
+#if defined (cygwin32_TARGET_OS)
+#define RTS_MINGW_ONLY_SYMBOLS /**/
+/* Don't have the ability to read import libs / archives, so
+ * we have to stupidly list a lot of what libcygwin.a
+ * exports; sigh. 
+ */
+#define RTS_CYGWIN_ONLY_SYMBOLS                 \
+      SymX(regfree)                             \
+      SymX(regexec)                             \
+      SymX(regerror)                            \
+      SymX(regcomp)                             \
+      SymX(__errno)                             \
+      SymX(access)                              \
+      SymX(chmod)                               \
+      SymX(chdir)                               \
+      SymX(close)                               \
+      SymX(creat)                               \
+      SymX(dup)                                 \
+      SymX(dup2)                                \
+      SymX(fstat)                               \
+      SymX(fcntl)                               \
+      SymX(getcwd)                              \
+      SymX(getenv)                              \
+      SymX(lseek)                               \
+      SymX(open)                                \
+      SymX(fpathconf)                           \
+      SymX(pathconf)                            \
+      SymX(stat)                                \
+      SymX(pow)                                 \
+      SymX(tanh)                                \
+      SymX(cosh)                                \
+      SymX(sinh)                                \
+      SymX(atan)                                \
+      SymX(acos)                                \
+      SymX(asin)                                \
+      SymX(tan)                                 \
+      SymX(cos)                                 \
+      SymX(sin)                                 \
+      SymX(exp)                                 \
+      SymX(log)                                 \
+      SymX(sqrt)                                \
+      SymX(localtime_r)                         \
+      SymX(gmtime_r)                            \
+      SymX(mktime)                              \
+      Sym(_imp___tzname)                        \
+      SymX(gettimeofday)                        \
+      SymX(timezone)                            \
+      SymX(tcgetattr)                           \
+      SymX(tcsetattr)                           \
+      SymX(memcpy)                              \
+      SymX(memmove)                             \
+      SymX(realloc)                             \
+      SymX(malloc)                              \
+      SymX(free)                                \
+      SymX(fork)                                \
+      SymX(lstat)                               \
+      SymX(isatty)                              \
+      SymX(mkdir)                               \
+      SymX(opendir)                             \
+      SymX(readdir)                             \
+      SymX(rewinddir)                           \
+      SymX(closedir)                            \
+      SymX(link)                                \
+      SymX(mkfifo)                              \
+      SymX(pipe)                                \
+      SymX(read)                                \
+      SymX(rename)                              \
+      SymX(rmdir)                               \
+      SymX(select)                              \
+      SymX(system)                              \
+      SymX(write)                               \
+      SymX(strcmp)                              \
+      SymX(strcpy)                              \
+      SymX(strncpy)                             \
+      SymX(strerror)                            \
+      SymX(sigaddset)                           \
+      SymX(sigemptyset)                         \
+      SymX(sigprocmask)                         \
+      SymX(umask)                               \
+      SymX(uname)                               \
+      SymX(unlink)                              \
+      SymX(utime)                               \
+      SymX(waitpid)
+
+#elif !defined(mingw32_TARGET_OS)
+#define RTS_MINGW_ONLY_SYMBOLS /**/
+#define RTS_CYGWIN_ONLY_SYMBOLS /**/
+#else /* defined(mingw32_TARGET_OS) */
+#define RTS_POSIX_ONLY_SYMBOLS  /**/
+#define RTS_CYGWIN_ONLY_SYMBOLS /**/
+
+/* Extra syms gen'ed by mingw-2's gcc-3.2: */
+#if __GNUC__>=3
+#define RTS_MINGW_EXTRA_SYMS                    \
+      Sym(_imp____mb_cur_max)                   \
+      Sym(_imp___pctype)            
 #else
-
-#define RTS_POSIX_ONLY_SYMBOLS
+#define RTS_MINGW_EXTRA_SYMS
+#endif
 
 /* These are statically linked from the mingw libraries into the ghc
    executable, so we have to employ this hack. */
 #define RTS_MINGW_ONLY_SYMBOLS                  \
+      SymX(asyncReadzh_fast)                   \
+      SymX(asyncWritezh_fast)                  \
+      SymX(asyncDoProczh_fast)                 \
       SymX(memset)                              \
       SymX(inet_ntoa)                           \
       SymX(inet_addr)                           \
@@ -137,40 +283,230 @@ typedef struct _RtsSymbolVal {
       Sym(mktime)                               \
       Sym(_imp___timezone)                      \
       Sym(_imp___tzname)                        \
+      Sym(_imp___iob)                           \
       Sym(localtime)                            \
       Sym(gmtime)                               \
-      SymX(getenv)                              \
-      SymX(free)                                \
-      SymX(rename)                              \
       Sym(opendir)                              \
       Sym(readdir)                              \
-      Sym(closedir)                             \
-      SymX(GetCurrentProcess)                   \
-      SymX(GetProcessTimes)                     \
-      SymX(CloseHandle)                         \
-      SymX(GetExitCodeProcess)                  \
-      SymX(WaitForSingleObject)                 \
-      SymX(CreateProcessA)                      \
-      SymX(_errno)
+      Sym(rewinddir)                            \
+      RTS_MINGW_EXTRA_SYMS                      \
+      Sym(closedir)
 #endif
 
+#ifndef SMP
+# define MAIN_CAP_SYM SymX(MainCapability)
+#else
+# define MAIN_CAP_SYM
+#endif
 
 #define RTS_SYMBOLS                            \
-      SymX(MainRegTable)                       \
-      Sym(stg_gc_enter_1)                      \
-      Sym(stg_gc_noregs)                       \
-      Sym(stg_gc_seq_1)                                \
-      Sym(stg_gc_d1)                           \
-      Sym(stg_gc_f1)                           \
-      Sym(stg_gc_ut_1_0)                       \
-      Sym(stg_gc_ut_0_1)                       \
-      Sym(stg_gc_unpt_r1)                      \
-      Sym(stg_gc_unbx_r1)                      \
-      Sym(stg_chk_0)                           \
-      Sym(stg_chk_1)                           \
-      Sym(stg_gen_chk)                         \
-      SymX(stg_exit)                           \
-      SymX(stg_update_PAP)                     \
+      Maybe_ForeignObj                         \
+      Maybe_Stable_Names                       \
+      Sym(StgReturn)                           \
+      SymX(stg_enter_info)                     \
+      SymX(stg_enter_ret)                      \
+      SymX(stg_gc_void_info)                   \
+      SymX(__stg_gc_enter_1)                   \
+      SymX(stg_gc_noregs)                      \
+      SymX(stg_gc_unpt_r1_info)                        \
+      SymX(stg_gc_unpt_r1)                     \
+      SymX(stg_gc_unbx_r1_info)                        \
+      SymX(stg_gc_unbx_r1)                     \
+      SymX(stg_gc_f1_info)                     \
+      SymX(stg_gc_f1)                          \
+      SymX(stg_gc_d1_info)                     \
+      SymX(stg_gc_d1)                          \
+      SymX(stg_gc_l1_info)                     \
+      SymX(stg_gc_l1)                          \
+      SymX(__stg_gc_fun)                       \
+      SymX(stg_gc_fun_info)                    \
+      SymX(stg_gc_fun_ret)                     \
+      SymX(stg_gc_gen)                         \
+      SymX(stg_gc_gen_info)                    \
+      SymX(stg_gc_gen_hp)                      \
+      SymX(stg_gc_ut)                          \
+      SymX(stg_gen_yield)                      \
+      SymX(stg_yield_noregs)                   \
+      SymX(stg_yield_to_interpreter)           \
+      SymX(stg_gen_block)                      \
+      SymX(stg_block_noregs)                   \
+      SymX(stg_block_1)                                \
+      SymX(stg_block_takemvar)                 \
+      SymX(stg_block_putmvar)                  \
+      SymX(stg_seq_frame_info)                 \
+      SymX(ErrorHdrHook)                       \
+      MAIN_CAP_SYM                              \
+      SymX(MallocFailHook)                     \
+      SymX(OnExitHook)                         \
+      SymX(OutOfHeapHook)                      \
+      SymX(PatErrorHdrHook)                    \
+      SymX(PostTraceHook)                      \
+      SymX(PreTraceHook)                       \
+      SymX(StackOverflowHook)                  \
+      SymX(__encodeDouble)                     \
+      SymX(__encodeFloat)                      \
+      SymX(__gmpn_gcd_1)                       \
+      SymX(__gmpz_cmp)                         \
+      SymX(__gmpz_cmp_si)                      \
+      SymX(__gmpz_cmp_ui)                      \
+      SymX(__gmpz_get_si)                      \
+      SymX(__gmpz_get_ui)                      \
+      SymX(__int_encodeDouble)                 \
+      SymX(__int_encodeFloat)                  \
+      SymX(andIntegerzh_fast)                  \
+      SymX(blockAsyncExceptionszh_fast)                \
+      SymX(catchzh_fast)                       \
+      SymX(cmp_thread)                         \
+      SymX(complementIntegerzh_fast)           \
+      SymX(cmpIntegerzh_fast)                  \
+      SymX(cmpIntegerIntzh_fast)               \
+      SymX(createAdjustor)                     \
+      SymX(decodeDoublezh_fast)                        \
+      SymX(decodeFloatzh_fast)                 \
+      SymX(defaultsHook)                       \
+      SymX(delayzh_fast)                       \
+      SymX(deRefWeakzh_fast)                   \
+      SymX(deRefStablePtrzh_fast)              \
+      SymX(divExactIntegerzh_fast)             \
+      SymX(divModIntegerzh_fast)               \
+      SymX(forkzh_fast)                                \
+      SymX(forkProcess)                                \
+      SymX(forkOS_createThread)                        \
+      SymX(freeHaskellFunctionPtr)             \
+      SymX(freeStablePtr)                      \
+      SymX(gcdIntegerzh_fast)                  \
+      SymX(gcdIntegerIntzh_fast)               \
+      SymX(gcdIntzh_fast)                      \
+      SymX(genSymZh)                           \
+      SymX(getProgArgv)                                \
+      SymX(getStablePtr)                       \
+      SymX(int2Integerzh_fast)                 \
+      SymX(integer2Intzh_fast)                 \
+      SymX(integer2Wordzh_fast)                        \
+      SymX(isCurrentThreadBoundzh_fast)                \
+      SymX(isDoubleDenormalized)               \
+      SymX(isDoubleInfinite)                   \
+      SymX(isDoubleNaN)                                \
+      SymX(isDoubleNegativeZero)               \
+      SymX(isEmptyMVarzh_fast)                 \
+      SymX(isFloatDenormalized)                        \
+      SymX(isFloatInfinite)                    \
+      SymX(isFloatNaN)                         \
+      SymX(isFloatNegativeZero)                        \
+      SymX(killThreadzh_fast)                  \
+      SymX(makeStablePtrzh_fast)               \
+      SymX(minusIntegerzh_fast)                        \
+      SymX(mkApUpd0zh_fast)                    \
+      SymX(myThreadIdzh_fast)                  \
+      SymX(labelThreadzh_fast)                  \
+      SymX(newArrayzh_fast)                    \
+      SymX(newBCOzh_fast)                      \
+      SymX(newByteArrayzh_fast)                        \
+      SymX_redirect(newCAF, newDynCAF)         \
+      SymX(newMVarzh_fast)                     \
+      SymX(newMutVarzh_fast)                   \
+      SymX(atomicModifyMutVarzh_fast)          \
+      SymX(newPinnedByteArrayzh_fast)          \
+      SymX(orIntegerzh_fast)                   \
+      SymX(performGC)                          \
+      SymX(plusIntegerzh_fast)                 \
+      SymX(prog_argc)                          \
+      SymX(prog_argv)                          \
+      SymX(putMVarzh_fast)                     \
+      SymX(quotIntegerzh_fast)                 \
+      SymX(quotRemIntegerzh_fast)              \
+      SymX(raisezh_fast)                       \
+      SymX(raiseIOzh_fast)                     \
+      SymX(remIntegerzh_fast)                  \
+      SymX(resetNonBlockingFd)                 \
+      SymX(resumeThread)                       \
+      SymX(rts_apply)                          \
+      SymX(rts_checkSchedStatus)               \
+      SymX(rts_eval)                           \
+      SymX(rts_evalIO)                         \
+      SymX(rts_evalLazyIO)                     \
+      SymX(rts_evalStableIO)                   \
+      SymX(rts_eval_)                          \
+      SymX(rts_getBool)                                \
+      SymX(rts_getChar)                                \
+      SymX(rts_getDouble)                      \
+      SymX(rts_getFloat)                       \
+      SymX(rts_getInt)                         \
+      SymX(rts_getInt32)                       \
+      SymX(rts_getPtr)                         \
+      SymX(rts_getFunPtr)                      \
+      SymX(rts_getStablePtr)                   \
+      SymX(rts_getThreadId)                    \
+      SymX(rts_getWord)                                \
+      SymX(rts_getWord32)                      \
+      SymX(rts_lock)                           \
+      SymX(rts_mkBool)                         \
+      SymX(rts_mkChar)                         \
+      SymX(rts_mkDouble)                       \
+      SymX(rts_mkFloat)                                \
+      SymX(rts_mkInt)                          \
+      SymX(rts_mkInt16)                                \
+      SymX(rts_mkInt32)                                \
+      SymX(rts_mkInt64)                                \
+      SymX(rts_mkInt8)                         \
+      SymX(rts_mkPtr)                          \
+      SymX(rts_mkFunPtr)                       \
+      SymX(rts_mkStablePtr)                    \
+      SymX(rts_mkString)                       \
+      SymX(rts_mkWord)                         \
+      SymX(rts_mkWord16)                       \
+      SymX(rts_mkWord32)                       \
+      SymX(rts_mkWord64)                       \
+      SymX(rts_mkWord8)                                \
+      SymX(rts_unlock)                         \
+      SymX(rtsSupportsBoundThreads)            \
+      SymX(run_queue_hd)                       \
+      SymX(__hscore_get_saved_termios)         \
+      SymX(__hscore_set_saved_termios)         \
+      SymX(setProgArgv)                                \
+      SymX(startupHaskell)                     \
+      SymX(shutdownHaskell)                    \
+      SymX(shutdownHaskellAndExit)             \
+      SymX(stable_ptr_table)                   \
+      SymX(stackOverflow)                      \
+      SymX(stg_CAF_BLACKHOLE_info)             \
+      SymX(stg_BLACKHOLE_BQ_info)              \
+      SymX(awakenBlockedQueue)                 \
+      SymX(stg_CHARLIKE_closure)               \
+      SymX(stg_EMPTY_MVAR_info)                        \
+      SymX(stg_IND_STATIC_info)                        \
+      SymX(stg_INTLIKE_closure)                        \
+      SymX(stg_MUT_ARR_PTRS_FROZEN_info)       \
+      SymX(stg_WEAK_info)                       \
+      SymX(stg_ap_v_info)                      \
+      SymX(stg_ap_f_info)                      \
+      SymX(stg_ap_d_info)                      \
+      SymX(stg_ap_l_info)                      \
+      SymX(stg_ap_n_info)                      \
+      SymX(stg_ap_p_info)                      \
+      SymX(stg_ap_pv_info)                     \
+      SymX(stg_ap_pp_info)                     \
+      SymX(stg_ap_ppv_info)                    \
+      SymX(stg_ap_ppp_info)                    \
+      SymX(stg_ap_pppp_info)                   \
+      SymX(stg_ap_ppppp_info)                  \
+      SymX(stg_ap_pppppp_info)                 \
+      SymX(stg_ap_ppppppp_info)                        \
+      SymX(stg_ap_0_ret)                       \
+      SymX(stg_ap_v_ret)                       \
+      SymX(stg_ap_f_ret)                       \
+      SymX(stg_ap_d_ret)                       \
+      SymX(stg_ap_l_ret)                       \
+      SymX(stg_ap_n_ret)                       \
+      SymX(stg_ap_p_ret)                       \
+      SymX(stg_ap_pv_ret)                      \
+      SymX(stg_ap_pp_ret)                      \
+      SymX(stg_ap_ppv_ret)                     \
+      SymX(stg_ap_ppp_ret)                     \
+      SymX(stg_ap_pppp_ret)                    \
+      SymX(stg_ap_ppppp_ret)                   \
+      SymX(stg_ap_pppppp_ret)                  \
+      SymX(stg_ap_ppppppp_ret)                 \
       SymX(stg_ap_1_upd_info)                  \
       SymX(stg_ap_2_upd_info)                  \
       SymX(stg_ap_3_upd_info)                  \
@@ -179,7 +515,14 @@ typedef struct _RtsSymbolVal {
       SymX(stg_ap_6_upd_info)                  \
       SymX(stg_ap_7_upd_info)                  \
       SymX(stg_ap_8_upd_info)                  \
+      SymX(stg_exit)                           \
       SymX(stg_sel_0_upd_info)                 \
+      SymX(stg_sel_10_upd_info)                        \
+      SymX(stg_sel_11_upd_info)                        \
+      SymX(stg_sel_12_upd_info)                        \
+      SymX(stg_sel_13_upd_info)                        \
+      SymX(stg_sel_14_upd_info)                        \
+      SymX(stg_sel_15_upd_info)                        \
       SymX(stg_sel_1_upd_info)                 \
       SymX(stg_sel_2_upd_info)                 \
       SymX(stg_sel_3_upd_info)                 \
@@ -189,196 +532,81 @@ typedef struct _RtsSymbolVal {
       SymX(stg_sel_7_upd_info)                 \
       SymX(stg_sel_8_upd_info)                 \
       SymX(stg_sel_9_upd_info)                 \
-      SymX(stg_sel_10_upd_info)                        \
-      SymX(stg_sel_11_upd_info)                        \
-      SymX(stg_sel_12_upd_info)                        \
-      SymX(stg_sel_13_upd_info)                        \
-      SymX(stg_sel_14_upd_info)                        \
-      SymX(stg_sel_15_upd_info)                        \
       SymX(stg_upd_frame_info)                 \
-      SymX(stg_seq_frame_info)                 \
-      SymX(stg_CAF_BLACKHOLE_info)             \
-      SymX(stg_IND_STATIC_info)                        \
-      SymX(stg_EMPTY_MVAR_info)                        \
-      SymX(stg_MUT_ARR_PTRS_FROZEN_info)       \
-      SymX(stg_WEAK_info)                       \
-      SymX(stg_CHARLIKE_closure)               \
-      SymX(stg_INTLIKE_closure)                        \
-      SymX(newCAF)                             \
-      SymX(newBCOzh_fast)                      \
-      SymX(mkApUpd0zh_fast)                    \
-      SymX(putMVarzh_fast)                     \
-      SymX(newMVarzh_fast)                     \
+      SymX(suspendThread)                      \
       SymX(takeMVarzh_fast)                    \
-      SymX(tryTakeMVarzh_fast)                 \
+      SymX(timesIntegerzh_fast)                        \
       SymX(tryPutMVarzh_fast)                  \
-      SymX(catchzh_fast)                       \
-      SymX(raisezh_fast)                       \
-      SymX(forkzh_fast)                                \
-      SymX(delayzh_fast)                       \
-      SymX(yieldzh_fast)                       \
-      SymX(killThreadzh_fast)                  \
+      SymX(tryTakeMVarzh_fast)                 \
+      SymX(unblockAsyncExceptionszh_fast)      \
+      SymX(unsafeThawArrayzh_fast)             \
       SymX(waitReadzh_fast)                    \
       SymX(waitWritezh_fast)                   \
-      SymX(suspendThread)                      \
-      SymX(resumeThread)                       \
-      SymX(stackOverflow)                      \
-      SymX(int2Integerzh_fast)                 \
       SymX(word2Integerzh_fast)                        \
-      Maybe_ForeignObj                         \
-      SymX(__encodeDouble)                     \
-      SymX(decodeDoublezh_fast)                        \
-      SymX(decodeFloatzh_fast)                 \
-      SymX(gcdIntegerzh_fast)                  \
-      SymX(newArrayzh_fast)                    \
-      SymX(unsafeThawArrayzh_fast)             \
-      SymX(newByteArrayzh_fast)                        \
-      SymX(newMutVarzh_fast)                   \
-      SymX(quotRemIntegerzh_fast)              \
-      SymX(quotIntegerzh_fast)                 \
-      SymX(remIntegerzh_fast)                  \
-      SymX(divExactIntegerzh_fast)             \
-      SymX(divModIntegerzh_fast)               \
-      SymX(timesIntegerzh_fast)                        \
-      SymX(minusIntegerzh_fast)                        \
-      SymX(plusIntegerzh_fast)                 \
-      SymX(andIntegerzh_fast)                  \
-      SymX(orIntegerzh_fast)                   \
       SymX(xorIntegerzh_fast)                  \
-      SymX(complementIntegerzh_fast)           \
-      Maybe_Stable_Names                       \
-      SymX(blockAsyncExceptionszh_fast)                \
-      SymX(unblockAsyncExceptionszh_fast)      \
-      SymX(isDoubleNaN)                                \
-      SymX(isDoubleInfinite)                   \
-      SymX(isDoubleDenormalized)               \
-      SymX(isDoubleNegativeZero)               \
-      SymX(__encodeFloat)                      \
-      SymX(isFloatNaN)                         \
-      SymX(isFloatInfinite)                    \
-      SymX(isFloatDenormalized)                        \
-      SymX(isFloatNegativeZero)                        \
-      SymX(__int_encodeFloat)                  \
-      SymX(__int_encodeDouble)                 \
-      SymX(__gmpz_cmp_si)                      \
-      SymX(__gmpz_cmp_ui)                      \
-      SymX(__gmpz_cmp)                         \
-      SymX(__gmpn_gcd_1)                       \
-      SymX(__gmpz_get_si)                      \
-      SymX(__gmpz_get_ui)                      \
-      SymX(prog_argv)                          \
-      SymX(prog_argc)                          \
-      SymX(resetNonBlockingFd)                 \
-      SymX(performGC)                          \
-      SymX(getStablePtr)                       \
-      SymX(stable_ptr_table)                   \
-      SymX(shutdownHaskellAndExit)             \
-      Sym(stg_enterStackTop)                   \
-      Sym(stg_yield_to_interpreter)            \
-      Sym(StgReturn)                           \
-      Sym(init_stack)                          \
-      SymX(cmp_thread)                         \
-      Sym(__init_PrelGHC)                      \
-      SymX(freeHaskellFunctionPtr)             \
-      SymX(OnExitHook)                         \
-      SymX(ErrorHdrHook)                       \
-      SymX(NoRunnableThreadsHook)              \
-      SymX(StackOverflowHook)                  \
-      SymX(OutOfHeapHook)                      \
-      SymX(MallocFailHook)                     \
-      SymX(PatErrorHdrHook)                    \
-      SymX(defaultsHook)                       \
-      SymX(PreTraceHook)                       \
-      SymX(PostTraceHook)                      \
-      SymX(createAdjustor)                     \
-      SymX(rts_mkChar)                         \
-      SymX(rts_mkInt)                          \
-      SymX(rts_mkInt8)                         \
-      SymX(rts_mkInt16)                                \
-      SymX(rts_mkInt32)                                \
-      SymX(rts_mkInt64)                                \
-      SymX(rts_mkWord)                         \
-      SymX(rts_mkWord8)                                \
-      SymX(rts_mkWord16)                       \
-      SymX(rts_mkWord32)                       \
-      SymX(rts_mkWord64)                       \
-      SymX(rts_mkPtr)                          \
-      SymX(rts_mkFloat)                                \
-      SymX(rts_mkDouble)                       \
-      SymX(rts_mkStablePtr)                    \
-      SymX(rts_mkBool)                         \
-      SymX(rts_mkString)                       \
-      SymX(rts_apply)                          \
-      SymX(rts_mkAddr)                         \
-      SymX(rts_getChar)                                \
-      SymX(rts_getInt)                         \
-      SymX(rts_getInt32)                       \
-      SymX(rts_getWord)                                \
-      SymX(rts_getWord32)                      \
-      SymX(rts_getPtr)                         \
-      SymX(rts_getFloat)                       \
-      SymX(rts_getDouble)                      \
-      SymX(rts_getStablePtr)                   \
-      SymX(rts_getBool)                                \
-      SymX(rts_getAddr)                                \
-      SymX(rts_eval)                           \
-      SymX(rts_eval_)                          \
-      SymX(rts_evalIO)                         \
-      SymX(rts_evalLazyIO)                     \
-      SymX(rts_checkSchedStatus)
+      SymX(yieldzh_fast)
 
-#ifndef SUPPORT_LONG_LONGS
-#define RTS_LONG_LONG_SYMS /* nothing */
-#else
+#ifdef SUPPORT_LONG_LONGS
 #define RTS_LONG_LONG_SYMS                     \
-      SymX(stg_gtWord64)                       \
-      SymX(stg_geWord64)                       \
-      SymX(stg_eqWord64)                       \
-      SymX(stg_neWord64)                       \
-      SymX(stg_ltWord64)                       \
-      SymX(stg_leWord64)                       \
-      SymX(stg_gtInt64)                                \
-      SymX(stg_geInt64)                                \
-      SymX(stg_eqInt64)                                \
-      SymX(stg_neInt64)                                \
-      SymX(stg_ltInt64)                                \
-      SymX(stg_leInt64)                                \
-      SymX(stg_remWord64)                      \
-      SymX(stg_quotWord64)                     \
-      SymX(stg_remInt64)                       \
-      SymX(stg_quotInt64)                      \
-      SymX(stg_negateInt64)                    \
-      SymX(stg_plusInt64)                      \
-      SymX(stg_minusInt64)                     \
-      SymX(stg_timesInt64)                     \
-      SymX(stg_and64)                          \
-      SymX(stg_or64)                           \
-      SymX(stg_xor64)                          \
-      SymX(stg_not64)                          \
-      SymX(stg_shiftL64)                       \
-      SymX(stg_shiftRL64)                      \
-      SymX(stg_iShiftL64)                      \
-      SymX(stg_iShiftRL64)                     \
-      SymX(stg_iShiftRA64)                     \
-      SymX(stg_intToInt64)                     \
-      SymX(stg_int64ToInt)                     \
-      SymX(stg_int64ToWord64)                  \
-      SymX(stg_wordToWord64)                   \
-      SymX(stg_word64ToWord)                   \
-      SymX(stg_word64ToInt64)                  \
       SymX(int64ToIntegerzh_fast)              \
       SymX(word64ToIntegerzh_fast)
-#endif /* SUPPORT_LONG_LONGS */
+#else
+#define RTS_LONG_LONG_SYMS /* nothing */
+#endif
+
+#ifdef HAVE_TERMIOS_H
+#define RTS_TERMIOS_SYMS                        \
+      Sym(saved_termios)
+#else
+#define RTS_TERMIOS_SYMS /* nothing */
+#endif
+
+// 64-bit support functions in libgcc.a
+#if defined(__GNUC__) && SIZEOF_VOID_P <= 4
+#define RTS_LIBGCC_SYMBOLS                     \
+      Sym(__divdi3)                             \
+      Sym(__udivdi3)                            \
+      Sym(__moddi3)                             \
+      Sym(__umoddi3)                           \
+      Sym(__ashldi3)                           \
+      Sym(__ashrdi3)                           \
+      Sym(__lshrdi3)                           \
+      Sym(__eprintf)
+#elif defined(ia64_TARGET_ARCH)
+#define RTS_LIBGCC_SYMBOLS                     \
+      Sym(__divdi3)                            \
+      Sym(__udivdi3)                            \
+      Sym(__moddi3)                            \
+      Sym(__umoddi3)                           \
+      Sym(__divsf3)                            \
+      Sym(__divdf3)
+#else
+#define RTS_LIBGCC_SYMBOLS
+#endif
+
+#ifdef darwin_TARGET_OS
+      // Symbols that don't have a leading underscore
+      // on Mac OS X. They have to receive special treatment,
+      // see machoInitSymbolsWithoutUnderscore()
+#define RTS_MACHO_NOUNDERLINE_SYMBOLS          \
+      Sym(saveFP)                              \
+      Sym(restFP)
+#endif
 
 /* entirely bogus claims about types of these symbols */
-#define Sym(vvv)  extern void (vvv);
+#define Sym(vvv)  extern void vvv(void);
 #define SymX(vvv) /**/
+#define SymX_redirect(vvv,xxx) /**/
 RTS_SYMBOLS
 RTS_LONG_LONG_SYMS
 RTS_POSIX_ONLY_SYMBOLS
 RTS_MINGW_ONLY_SYMBOLS
+RTS_CYGWIN_ONLY_SYMBOLS
+RTS_TERMIOS_SYMS
+RTS_LIBGCC_SYMBOLS
 #undef Sym
 #undef SymX
+#undef SymX_redirect
 
 #ifdef LEADING_UNDERSCORE
 #define MAYBE_LEADING_UNDERSCORE_STR(s) ("_" s)
@@ -390,18 +618,64 @@ RTS_MINGW_ONLY_SYMBOLS
                     (void*)(&(vvv)) },
 #define SymX(vvv) Sym(vvv)
 
+// SymX_redirect allows us to redirect references to one symbol to
+// another symbol.  See newCAF/newDynCAF for an example.
+#define SymX_redirect(vvv,xxx) \
+    { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
+      (void*)(&(xxx)) },
+
 static RtsSymbolVal rtsSyms[] = {
       RTS_SYMBOLS
       RTS_LONG_LONG_SYMS
       RTS_POSIX_ONLY_SYMBOLS
       RTS_MINGW_ONLY_SYMBOLS
+      RTS_CYGWIN_ONLY_SYMBOLS
+      RTS_LIBGCC_SYMBOLS
       { 0, 0 } /* sentinel */
 };
 
 /* -----------------------------------------------------------------------------
+ * Insert symbols into hash tables, checking for duplicates.
+ */
+static void ghciInsertStrHashTable ( char* obj_name,
+                                     HashTable *table,
+                                     char* key,
+                                     void *data
+                                  )
+{
+   if (lookupHashTable(table, (StgWord)key) == NULL)
+   {
+      insertStrHashTable(table, (StgWord)key, data);
+      return;
+   }
+   fprintf(stderr,
+      "\n\n"
+      "GHCi runtime linker: fatal error: I found a duplicate definition for symbol\n"
+      "   %s\n"
+      "whilst processing object file\n"
+      "   %s\n"
+      "This could be caused by:\n"
+      "   * Loading two different object files which export the same symbol\n"
+      "   * Specifying the same object file twice on the GHCi command line\n"
+      "   * An incorrect `package.conf' entry, causing some object to be\n"
+      "     loaded twice.\n"
+      "GHCi cannot safely continue in this situation.  Exiting now.  Sorry.\n"
+      "\n",
+      (char*)key,
+      obj_name
+   );
+   exit(1);
+}
+
+
+/* -----------------------------------------------------------------------------
  * initialize the object linker
  */
-#if defined(OBJFORMAT_ELF)
+
+
+static int linker_init_done = 0 ;
+
+#if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
 static void *dl_prog_handle;
 #endif
 
@@ -410,27 +684,47 @@ initLinker( void )
 {
     RtsSymbolVal *sym;
 
+    /* Make initLinker idempotent, so we can call it
+       before evey relevant operation; that means we
+       don't need to initialise the linker separately */
+    if (linker_init_done == 1) { return; } else {
+      linker_init_done = 1;
+    }
+
     symhash = allocStrHashTable();
 
     /* populate the symbol table with stuff from the RTS */
     for (sym = rtsSyms; sym->lbl != NULL; sym++) {
-       insertStrHashTable(symhash, sym->lbl, sym->addr);
+       ghciInsertStrHashTable("(GHCi built-in symbols)",
+                               symhash, sym->lbl, sym->addr);
     }
-#   if defined(OBJFORMAT_ELF)
+#   if defined(OBJFORMAT_MACHO)
+    machoInitSymbolsWithoutUnderscore();
+#   endif
+
+#   if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
     dl_prog_handle = dlopen(NULL, RTLD_LAZY);
 #   endif
 }
 
 /* -----------------------------------------------------------------------------
+ *                  Loading DLL or .so dynamic libraries
+ * -----------------------------------------------------------------------------
+ *
  * Add a DLL from which symbols may be found.  In the ELF case, just
  * do RTLD_GLOBAL-style add, so no further messing around needs to
  * happen in order that symbols in the loaded .so are findable --
  * lookupSymbol() will subsequently see them by dlsym on the program's
  * dl-handle.  Returns NULL if success, otherwise ptr to an err msg.
  *
- * In the PEi386 case, open the DLLs and put handles to them in a 
+ * In the PEi386 case, open the DLLs and put handles to them in a
  * linked list.  When looking for a symbol, try all handles in the
- * list.
+ * list.  This means that we need to load even DLLs that are guaranteed
+ * to be in the ghc.exe image already, just so we can get a handle
+ * to give to loadSymbol, so that we can find the symbols.  For such
+ * libraries, the LoadLibrary call should be a no-op except for returning
+ * the handle.
+ * 
  */
 
 #if defined(OBJFORMAT_PEi386)
@@ -441,32 +735,25 @@ typedef
       char*              name;
       struct _OpenedDLL* next;
       HINSTANCE instance;
-   } 
+   }
    OpenedDLL;
 
 /* A list thereof. */
 static OpenedDLL* opened_dlls = NULL;
 #endif
 
-
-
-char*
-addDLL ( char* path, char* dll_name )
+char *
+addDLL( char *dll_name )
 {
-#  if defined(OBJFORMAT_ELF)
+#  if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
+   /* ------------------- ELF DLL loader ------------------- */
    void *hdl;
-   char *buf;
    char *errmsg;
 
-   if (path == NULL || strlen(path) == 0) {
-      buf = stgMallocBytes(strlen(dll_name) + 10, "addDll");
-      sprintf(buf, "lib%s.so", dll_name);
-   } else {
-      buf = stgMallocBytes(strlen(path) + 1 + strlen(dll_name) + 10, "addDll");
-      sprintf(buf, "%s/lib%s.so", path, dll_name);
-   }
-   hdl = dlopen(buf, RTLD_NOW | RTLD_GLOBAL );
-   free(buf);
+   initLinker();
+
+   hdl= dlopen(dll_name, RTLD_NOW | RTLD_GLOBAL);
+
    if (hdl == NULL) {
       /* dlopen failed; return a ptr to the error msg. */
       errmsg = dlerror();
@@ -478,14 +765,15 @@ addDLL ( char* path, char* dll_name )
    /*NOTREACHED*/
 
 #  elif defined(OBJFORMAT_PEi386)
+   /* ------------------- Win32 DLL loader ------------------- */
 
-   /* Add this DLL to the list of DLLs in which to search for symbols.
-      The path argument is ignored. */
    char*      buf;
    OpenedDLL* o_dll;
    HINSTANCE  instance;
 
-   /* fprintf(stderr, "\naddDLL; path=`%s', dll_name = `%s'\n", path, dll_name); */
+   initLinker();
+
+   /* fprintf(stderr, "\naddDLL; dll_name = `%s'\n", dll_name); */
 
    /* See if we've already got it, and ignore if so. */
    for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
@@ -493,15 +781,32 @@ addDLL ( char* path, char* dll_name )
          return NULL;
    }
 
+   /* The file name has no suffix (yet) so that we can try
+      both foo.dll and foo.drv
+
+      The documentation for LoadLibrary says:
+       If no file name extension is specified in the lpFileName
+       parameter, the default library extension .dll is
+       appended. However, the file name string can include a trailing
+       point character (.) to indicate that the module name has no
+       extension. */
+
    buf = stgMallocBytes(strlen(dll_name) + 10, "addDLL");
    sprintf(buf, "%s.DLL", dll_name);
    instance = LoadLibrary(buf);
-   free(buf);
    if (instance == NULL) {
-     /* LoadLibrary failed; return a ptr to the error msg. */
-     return "addDLL: unknown error";
+        sprintf(buf, "%s.DRV", dll_name);      // KAA: allow loading of drivers (like winspool.drv)
+        instance = LoadLibrary(buf);
+        if (instance == NULL) {
+               stgFree(buf);
+
+           /* LoadLibrary failed; return a ptr to the error msg. */
+           return "addDLL: unknown error";
+        }
    }
+   stgFree(buf);
 
+   /* Add this DLL to the list of DLLs in which to search for symbols. */
    o_dll = stgMallocBytes( sizeof(OpenedDLL), "addDLL" );
    o_dll->name     = stgMallocBytes(1+strlen(dll_name), "addDLL");
    strcpy(o_dll->name, dll_name);
@@ -517,37 +822,65 @@ addDLL ( char* path, char* dll_name )
 
 /* -----------------------------------------------------------------------------
  * lookup a symbol in the hash table
- */  
+ */
 void *
 lookupSymbol( char *lbl )
 {
     void *val;
+    initLinker() ;
     ASSERT(symhash != NULL);
     val = lookupStrHashTable(symhash, lbl);
 
     if (val == NULL) {
 #       if defined(OBJFORMAT_ELF)
        return dlsym(dl_prog_handle, lbl);
+#       elif defined(OBJFORMAT_MACHO)
+       if(NSIsSymbolNameDefined(lbl)) {
+           NSSymbol symbol = NSLookupAndBindSymbol(lbl);
+           return NSAddressOfSymbol(symbol);
+       } else {
+           return NULL;
+       }
 #       elif defined(OBJFORMAT_PEi386)
         OpenedDLL* o_dll;
         void* sym;
         for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
-           /* fprintf(stderr, "look in %s for %s\n", o_dll->name, lbl); */
+         /* fprintf(stderr, "look in %s for %s\n", o_dll->name, lbl); */
+           if (lbl[0] == '_') {
+              /* HACK: if the name has an initial underscore, try stripping
+                 it off & look that up first. I've yet to verify whether there's
+                 a Rule that governs whether an initial '_' *should always* be
+                 stripped off when mapping from import lib name to the DLL name.
+              */
+              sym = GetProcAddress(o_dll->instance, (lbl+1));
+              if (sym != NULL) {
+               /*fprintf(stderr, "found %s in %s\n", lbl+1,o_dll->name); fflush(stderr);*/
+               return sym;
+             }
+           }
            sym = GetProcAddress(o_dll->instance, lbl);
-           if (sym != NULL) return sym;
+           if (sym != NULL) {
+            /*fprintf(stderr, "found %s in %s\n", lbl,o_dll->name); fflush(stderr);*/
+            return sym;
+          }
         }
         return NULL;
+#       else
+        ASSERT(2+2 == 5);
+        return NULL;
 #       endif
     } else {
        return val;
     }
 }
 
-static 
+static
+__attribute((unused))
 void *
 lookupLocalSymbol( ObjectCode* oc, char *lbl )
 {
     void *val;
+    initLinker() ;
     val = lookupStrHashTable(oc->lochash, lbl);
 
     if (val == NULL) {
@@ -559,6 +892,50 @@ lookupLocalSymbol( ObjectCode* oc, char *lbl )
 
 
 /* -----------------------------------------------------------------------------
+ * Debugging aid: look in GHCi's object symbol tables for symbols
+ * within DELTA bytes of the specified address, and show their names.
+ */
+#ifdef DEBUG
+void ghci_enquire ( char* addr );
+
+void ghci_enquire ( char* addr )
+{
+   int   i;
+   char* sym;
+   char* a;
+   const int DELTA = 64;
+   ObjectCode* oc;
+
+   initLinker();
+
+   for (oc = objects; oc; oc = oc->next) {
+      for (i = 0; i < oc->n_symbols; i++) {
+         sym = oc->symbols[i];
+         if (sym == NULL) continue;
+         // fprintf(stderr, "enquire %p %p\n", sym, oc->lochash);
+         a = NULL;
+         if (oc->lochash != NULL) {
+            a = lookupStrHashTable(oc->lochash, sym);
+        }
+         if (a == NULL) {
+            a = lookupStrHashTable(symhash, sym);
+        }
+         if (a == NULL) {
+            // fprintf(stderr, "ghci_enquire: can't find %s\n", sym);
+         }
+         else if (addr-DELTA <= a && a <= addr+DELTA) {
+            fprintf(stderr, "%p + %3d  ==  `%s'\n", addr, a - addr, sym);
+         }
+      }
+   }
+}
+#endif
+
+#ifdef ia64_TARGET_ARCH
+static unsigned int PLTSize(void);
+#endif
+
+/* -----------------------------------------------------------------------------
  * Load an obj (populate the global symbol table, but don't resolve yet)
  *
  * Returns: 1 if ok, 0 on error.
@@ -569,17 +946,37 @@ loadObj( char *path )
    ObjectCode* oc;
    struct stat st;
    int r, n;
+#ifdef USE_MMAP
+   int fd, pagesize;
+   void *map_addr;
+#else
    FILE *f;
+#endif
+
+   initLinker();
 
    /* fprintf(stderr, "loadObj %s\n", path ); */
-#  ifdef DEBUG
-   /* assert that we haven't already loaded this object */
-   { 
+
+   /* Check that we haven't already loaded this object.  Don't give up
+      at this stage; ocGetNames_* will barf later. */
+   {
        ObjectCode *o;
-       for (o = objects; o; o = o->next)
-          ASSERT(strcmp(o->fileName, path));
+       int is_dup = 0;
+       for (o = objects; o; o = o->next) {
+          if (0 == strcmp(o->fileName, path))
+             is_dup = 1;
+       }
+       if (is_dup) {
+        fprintf(stderr,
+            "\n\n"
+            "GHCi runtime linker: warning: looks like you're trying to load the\n"
+            "same object file twice:\n"
+            "   %s\n"
+            "GHCi will continue, but a duplicate-symbol error may shortly follow.\n"
+            "\n"
+            , path);
+       }
    }
-#  endif /* DEBUG */   
 
    oc = stgMallocBytes(sizeof(ObjectCode), "loadObj(oc)");
 
@@ -587,8 +984,10 @@ loadObj( char *path )
    oc->formatName = "ELF";
 #  elif defined(OBJFORMAT_PEi386)
    oc->formatName = "PEi386";
+#  elif defined(OBJFORMAT_MACHO)
+   oc->formatName = "Mach-O";
 #  else
-   free(oc);
+   stgFree(oc);
    barf("loadObj: not implemented on this platform");
 #  endif
 
@@ -600,31 +999,73 @@ loadObj( char *path )
    strcpy(oc->fileName, path);
 
    oc->fileSize          = st.st_size;
-   oc->image             = stgMallocBytes( st.st_size, "loadObj(image)" );
    oc->symbols           = NULL;
    oc->sections          = NULL;
    oc->lochash           = allocStrHashTable();
+   oc->proddables        = NULL;
 
    /* chain it onto the list of objects */
    oc->next              = objects;
    objects               = oc;
 
+#ifdef USE_MMAP
+#define ROUND_UP(x,size) ((x + size - 1) & ~(size - 1))
+
+   /* On many architectures malloc'd memory isn't executable, so we need to use mmap. */
+
+   fd = open(path, O_RDONLY);
+   if (fd == -1)
+      barf("loadObj: can't open `%s'", path);
+
+   pagesize = getpagesize();
+
+#ifdef ia64_TARGET_ARCH
+   /* The PLT needs to be right before the object */
+   n = ROUND_UP(PLTSize(), pagesize);
+   oc->plt = mmap(NULL, n, PROT_EXEC|PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+   if (oc->plt == MAP_FAILED)
+      barf("loadObj: can't allocate PLT");
+
+   oc->pltIndex = 0;
+   map_addr = oc->plt + n;
+#endif
+
+   n = ROUND_UP(oc->fileSize, pagesize);
+   oc->image = mmap(map_addr, n, PROT_EXEC|PROT_READ|PROT_WRITE, MAP_PRIVATE, fd, 0);
+   if (oc->image == MAP_FAILED)
+      barf("loadObj: can't map `%s'", path);
+
+   close(fd);
+
+#else /* !USE_MMAP */
+
+   oc->image = stgMallocBytes(oc->fileSize, "loadObj(image)");
+
    /* load the image into memory */
    f = fopen(path, "rb");
-   if (!f) {
+   if (!f)
        barf("loadObj: can't read `%s'", path);
-   }
+
    n = fread ( oc->image, 1, oc->fileSize, f );
-   if (n != oc->fileSize) {
-      fclose(f);
+   if (n != oc->fileSize)
       barf("loadObj: error whilst reading `%s'", path);
-   }
+
+   fclose(f);
+
+#endif /* USE_MMAP */
+
+#  if defined(OBJFORMAT_MACHO)
+   r = ocAllocateJumpIslands_MachO ( oc );
+   if (!r) { return r; }
+#endif
 
    /* verify the in-memory image */
 #  if defined(OBJFORMAT_ELF)
    r = ocVerifyImage_ELF ( oc );
 #  elif defined(OBJFORMAT_PEi386)
    r = ocVerifyImage_PEi386 ( oc );
+#  elif defined(OBJFORMAT_MACHO)
+   r = ocVerifyImage_MachO ( oc );
 #  else
    barf("loadObj: no verify method");
 #  endif
@@ -635,6 +1076,8 @@ loadObj( char *path )
    r = ocGetNames_ELF ( oc );
 #  elif defined(OBJFORMAT_PEi386)
    r = ocGetNames_PEi386 ( oc );
+#  elif defined(OBJFORMAT_MACHO)
+   r = ocGetNames_MachO ( oc );
 #  else
    barf("loadObj: no getNames method");
 #  endif
@@ -651,18 +1094,22 @@ loadObj( char *path )
  *
  * Returns: 1 if ok, 0 on error.
  */
-HsInt 
+HsInt
 resolveObjs( void )
 {
     ObjectCode *oc;
     int r;
 
+    initLinker();
+
     for (oc = objects; oc; oc = oc->next) {
        if (oc->status != OBJECT_RESOLVED) {
 #           if defined(OBJFORMAT_ELF)
            r = ocResolve_ELF ( oc );
 #           elif defined(OBJFORMAT_PEi386)
            r = ocResolve_PEi386 ( oc );
+#           elif defined(OBJFORMAT_MACHO)
+           r = ocResolve_MachO ( oc );
 #           else
            barf("resolveObjs: not implemented on this platform");
 #           endif
@@ -684,6 +1131,8 @@ unloadObj( char *path )
     ASSERT(symhash != NULL);
     ASSERT(objects != NULL);
 
+    initLinker(); 
+
     prev = NULL;
     for (oc = objects; oc; prev = oc, oc = oc->next) {
        if (!strcmp(oc->fileName,path)) {
@@ -691,7 +1140,7 @@ unloadObj( char *path )
            /* Remove all the mappings for the symbols within this
             * object..
             */
-           { 
+           {
                 int i;
                 for (i = 0; i < oc->n_symbols; i++) {
                    if (oc->symbols[i] != NULL) {
@@ -708,14 +1157,14 @@ unloadObj( char *path )
 
            /* We're going to leave this in place, in case there are
               any pointers from the heap into it: */
-           /* free(oc->image); */
-           free(oc->fileName);
-           free(oc->symbols);
-           free(oc->sections);
+           /* stgFree(oc->image); */
+           stgFree(oc->fileName);
+           stgFree(oc->symbols);
+           stgFree(oc->sections);
            /* The local hash table should have been freed at the end
                of the ocResolve_ call on it. */
             ASSERT(oc->lochash == NULL);
-           free(oc);
+           stgFree(oc);
            return 1;
        }
     }
@@ -724,17 +1173,96 @@ unloadObj( char *path )
     return 0;
 }
 
+/* -----------------------------------------------------------------------------
+ * Sanity checking.  For each ObjectCode, maintain a list of address ranges
+ * which may be prodded during relocation, and abort if we try and write
+ * outside any of these.
+ */
+static void addProddableBlock ( ObjectCode* oc, void* start, int size )
+{
+   ProddableBlock* pb
+      = stgMallocBytes(sizeof(ProddableBlock), "addProddableBlock");
+   /* fprintf(stderr, "aPB %p %p %d\n", oc, start, size); */
+   ASSERT(size > 0);
+   pb->start      = start;
+   pb->size       = size;
+   pb->next       = oc->proddables;
+   oc->proddables = pb;
+}
+
+static void checkProddableBlock ( ObjectCode* oc, void* addr )
+{
+   ProddableBlock* pb;
+   for (pb = oc->proddables; pb != NULL; pb = pb->next) {
+      char* s = (char*)(pb->start);
+      char* e = s + pb->size - 1;
+      char* a = (char*)addr;
+      /* Assumes that the biggest fixup involves a 4-byte write.  This
+         probably needs to be changed to 8 (ie, +7) on 64-bit
+         plats. */
+      if (a >= s && (a+3) <= e) return;
+   }
+   barf("checkProddableBlock: invalid fixup in runtime linker");
+}
+
+/* -----------------------------------------------------------------------------
+ * Section management.
+ */
+static void addSection ( ObjectCode* oc, SectionKind kind,
+                         void* start, void* end )
+{
+   Section* s   = stgMallocBytes(sizeof(Section), "addSection");
+   s->start     = start;
+   s->end       = end;
+   s->kind      = kind;
+   s->next      = oc->sections;
+   oc->sections = s;
+   /*
+   fprintf(stderr, "addSection: %p-%p (size %d), kind %d\n",
+                   start, ((char*)end)-1, end - start + 1, kind );
+   */
+}
+
+
+
 /* --------------------------------------------------------------------------
  * PEi386 specifics (Win32 targets)
  * ------------------------------------------------------------------------*/
 
-/* The information for this linker comes from 
-      Microsoft Portable Executable 
+/* The information for this linker comes from
+      Microsoft Portable Executable
       and Common Object File Format Specification
       revision 5.1 January 1998
    which SimonM says comes from the MS Developer Network CDs.
+
+   It can be found there (on older CDs), but can also be found
+   online at:
+
+      http://www.microsoft.com/hwdev/hardware/PECOFF.asp
+
+   (this is Rev 6.0 from February 1999).
+
+   Things move, so if that fails, try searching for it via
+
+      http://www.google.com/search?q=PE+COFF+specification
+
+   The ultimate reference for the PE format is the Winnt.h
+   header file that comes with the Platform SDKs; as always,
+   implementations will drift wrt their documentation.
+
+   A good background article on the PE format is Matt Pietrek's
+   March 1994 article in Microsoft System Journal (MSJ)
+   (Vol.9, No. 3): "Peering Inside the PE: A Tour of the
+   Win32 Portable Executable File Format." The info in there
+   has recently been updated in a two part article in
+   MSDN magazine, issues Feb and March 2002,
+   "Inside Windows: An In-Depth Look into the Win32 Portable
+   Executable File Format"
+
+   John Levine's book "Linkers and Loaders" contains useful
+   info on PE too.
 */
-      
+
 
 #if defined(OBJFORMAT_PEi386)
 
@@ -746,7 +1274,7 @@ typedef unsigned int   UInt32;
 typedef          int   Int32;
 
 
-typedef 
+typedef
    struct {
       UInt16 Machine;
       UInt16 NumberOfSections;
@@ -761,7 +1289,7 @@ typedef
 #define sizeof_COFF_header 20
 
 
-typedef 
+typedef
    struct {
       UChar  Name[8];
       UInt32 VirtualSize;
@@ -772,7 +1300,7 @@ typedef
       UInt32 PointerToLinenumbers;
       UInt16 NumberOfRelocations;
       UInt16 NumberOfLineNumbers;
-      UInt32 Characteristics; 
+      UInt32 Characteristics;
    }
    COFF_section;
 
@@ -824,6 +1352,7 @@ typedef
 /* From PE spec doc, section 4.1 */
 #define MYIMAGE_SCN_CNT_CODE             0x00000020
 #define MYIMAGE_SCN_CNT_INITIALIZED_DATA 0x00000040
+#define MYIMAGE_SCN_LNK_NRELOC_OVFL      0x01000000
 
 /* From PE spec doc, section 5.2.1 */
 #define MYIMAGE_REL_I386_DIR32           0x0006
@@ -832,7 +1361,7 @@ typedef
 
 /* We use myindex to calculate array addresses, rather than
    simply doing the normal subscript thing.  That's because
-   some of the above structs have sizes which are not 
+   some of the above structs have sizes which are not
    a whole number of words.  GCC rounds their sizes up to a
    whole number of words, which means that the address calcs
    arising from using normal C indexing or pointer arithmetic
@@ -887,7 +1416,7 @@ cstring_from_COFF_symbol_name ( UChar* name, UChar* strtab )
 {
    UChar* newstr;
    /* If the string is longer than 8 bytes, look in the
-      string table for it -- this will be correctly zero terminated. 
+      string table for it -- this will be correctly zero terminated.
    */
    if (name[0]==0 && name[1]==0 && name[2]==0 && name[3]==0) {
       UInt32 strtab_offset = * (UInt32*)(name+4);
@@ -913,23 +1442,23 @@ static COFF_section *
 findPEi386SectionCalled ( ObjectCode* oc,  char* name )
 {
    int i;
-   COFF_header* hdr 
+   COFF_header* hdr
       = (COFF_header*)(oc->image);
-   COFF_section* sectab 
+   COFF_section* sectab
       = (COFF_section*) (
-           ((UChar*)(oc->image)) 
+           ((UChar*)(oc->image))
            + sizeof_COFF_header + hdr->SizeOfOptionalHeader
         );
    for (i = 0; i < hdr->NumberOfSections; i++) {
       UChar* n1;
       UChar* n2;
-      COFF_section* section_i 
+      COFF_section* section_i
          = (COFF_section*)
            myindex ( sizeof_COFF_section, sectab, i );
       n1 = (UChar*) &(section_i->Name);
       n2 = name;
-      if (n1[0]==n2[0] && n1[1]==n2[1] && n1[2]==n2[2] && 
-          n1[3]==n2[3] && n1[4]==n2[4] && n1[5]==n2[5] && 
+      if (n1[0]==n2[0] && n1[1]==n2[1] && n1[2]==n2[2] &&
+          n1[3]==n2[3] && n1[4]==n2[4] && n1[5]==n2[5] &&
           n1[6]==n2[6] && n1[7]==n2[7])
          return section_i;
    }
@@ -944,7 +1473,7 @@ zapTrailingAtSign ( UChar* sym )
 #  define my_isdigit(c) ((c) >= '0' && (c) <= '9')
    int i, j;
    if (sym[0] == 0) return;
-   i = 0; 
+   i = 0;
    while (sym[i] != 0) i++;
    i--;
    j = i;
@@ -957,7 +1486,8 @@ zapTrailingAtSign ( UChar* sym )
 static int
 ocVerifyImage_PEi386 ( ObjectCode* oc )
 {
-   int i, j;
+   int i;
+   UInt32 j, noRelocs;
    COFF_header*  hdr;
    COFF_section* sectab;
    COFF_symbol*  symtab;
@@ -965,12 +1495,12 @@ ocVerifyImage_PEi386 ( ObjectCode* oc )
    /* fprintf(stderr, "\nLOADING %s\n", oc->fileName); */
    hdr = (COFF_header*)(oc->image);
    sectab = (COFF_section*) (
-               ((UChar*)(oc->image)) 
+               ((UChar*)(oc->image))
                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
             );
    symtab = (COFF_symbol*) (
                ((UChar*)(oc->image))
-               + hdr->PointerToSymbolTable 
+               + hdr->PointerToSymbolTable
             );
    strtab = ((UChar*)symtab)
             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
@@ -992,40 +1522,48 @@ ocVerifyImage_PEi386 ( ObjectCode* oc )
    }
    if ( (hdr->Characteristics & MYIMAGE_FILE_BYTES_REVERSED_HI)
         /* || !(hdr->Characteristics & MYIMAGE_FILE_32BIT_MACHINE) */ ) {
-      belch("Invalid PEi386 word size or endiannness: %d", 
+      belch("Invalid PEi386 word size or endiannness: %d",
             (int)(hdr->Characteristics));
       return 0;
    }
+   /* If the string table size is way crazy, this might indicate that
+      there are more than 64k relocations, despite claims to the
+      contrary.  Hence this test. */
    /* fprintf(stderr, "strtab size %d\n", * (UInt32*)strtab); */
-   if (* (UInt32*)strtab > 510000) {
+#if 0
+   if ( (*(UInt32*)strtab) > 600000 ) {
+      /* Note that 600k has no special significance other than being
+         big enough to handle the almost-2MB-sized lumps that
+         constitute HSwin32*.o. */
       belch("PEi386 object has suspiciously large string table; > 64k relocs?");
       return 0;
    }
+#endif
 
    /* No further verification after this point; only debug printing. */
    i = 0;
    IF_DEBUG(linker, i=1);
    if (i == 0) return 1;
 
-   fprintf ( stderr, 
+   fprintf ( stderr,
              "sectab offset = %d\n", ((UChar*)sectab) - ((UChar*)hdr) );
-   fprintf ( stderr, 
+   fprintf ( stderr,
              "symtab offset = %d\n", ((UChar*)symtab) - ((UChar*)hdr) );
-   fprintf ( stderr, 
+   fprintf ( stderr,
              "strtab offset = %d\n", ((UChar*)strtab) - ((UChar*)hdr) );
 
    fprintf ( stderr, "\n" );
-   fprintf ( stderr, 
+   fprintf ( stderr,
              "Machine:           0x%x\n", (UInt32)(hdr->Machine) );
-   fprintf ( stderr, 
+   fprintf ( stderr,
              "# sections:        %d\n",   (UInt32)(hdr->NumberOfSections) );
    fprintf ( stderr,
              "time/date:         0x%x\n", (UInt32)(hdr->TimeDateStamp) );
    fprintf ( stderr,
              "symtab offset:     %d\n",   (UInt32)(hdr->PointerToSymbolTable) );
-   fprintf ( stderr, 
+   fprintf ( stderr,
              "# symbols:         %d\n",   (UInt32)(hdr->NumberOfSymbols) );
-   fprintf ( stderr, 
+   fprintf ( stderr,
              "sz of opt hdr:     %d\n",   (UInt32)(hdr->SizeOfOptionalHeader) );
    fprintf ( stderr,
              "characteristics:   0x%x\n", (UInt32)(hdr->Characteristics) );
@@ -1037,54 +1575,72 @@ ocVerifyImage_PEi386 ( ObjectCode* oc )
       COFF_section* sectab_i
          = (COFF_section*)
            myindex ( sizeof_COFF_section, sectab, i );
-      fprintf ( stderr, 
+      fprintf ( stderr,
                 "\n"
                 "section %d\n"
                 "     name `",
-                i 
+                i
               );
       printName ( sectab_i->Name, strtab );
-      fprintf ( stderr, 
+      fprintf ( stderr,
                 "'\n"
                 "    vsize %d\n"
                 "    vaddr %d\n"
                 "  data sz %d\n"
                 " data off %d\n"
                 "  num rel %d\n"
-                "  off rel %d\n",
+                "  off rel %d\n"
+                "  ptr raw 0x%x\n",
                 sectab_i->VirtualSize,
                 sectab_i->VirtualAddress,
                 sectab_i->SizeOfRawData,
                 sectab_i->PointerToRawData,
                 sectab_i->NumberOfRelocations,
-                sectab_i->PointerToRelocations
+                sectab_i->PointerToRelocations,
+                sectab_i->PointerToRawData
               );
       reltab = (COFF_reloc*) (
                   ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
                );
 
-      for (j = 0; j < sectab_i->NumberOfRelocations; j++) {
+      if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
+       /* If the relocation field (a short) has overflowed, the
+        * real count can be found in the first reloc entry.
+        *
+        * See Section 4.1 (last para) of the PE spec (rev6.0).
+        */
+        COFF_reloc* rel = (COFF_reloc*)
+                           myindex ( sizeof_COFF_reloc, reltab, 0 );
+       noRelocs = rel->VirtualAddress;
+       j = 1;
+      } else {
+       noRelocs = sectab_i->NumberOfRelocations;
+        j = 0;
+      }
+
+      for (; j < noRelocs; j++) {
          COFF_symbol* sym;
          COFF_reloc* rel = (COFF_reloc*)
                            myindex ( sizeof_COFF_reloc, reltab, j );
-         fprintf ( stderr, 
+         fprintf ( stderr,
                    "        type 0x%-4x   vaddr 0x%-8x   name `",
-                   (UInt32)rel->Type, 
+                   (UInt32)rel->Type,
                    rel->VirtualAddress );
          sym = (COFF_symbol*)
                myindex ( sizeof_COFF_symbol, symtab, rel->SymbolTableIndex );
+        /* Hmm..mysterious looking offset - what's it for? SOF */
          printName ( sym->Name, strtab -10 );
          fprintf ( stderr, "'\n" );
       }
+
       fprintf ( stderr, "\n" );
    }
-
    fprintf ( stderr, "\n" );
    fprintf ( stderr, "string table has size 0x%x\n", * (UInt32*)strtab );
    fprintf ( stderr, "---START of string table---\n");
    for (i = 4; i < *(Int32*)strtab; i++) {
-      if (strtab[i] == 0) 
-         fprintf ( stderr, "\n"); else 
+      if (strtab[i] == 0)
+         fprintf ( stderr, "\n"); else
          fprintf( stderr, "%c", strtab[i] );
    }
    fprintf ( stderr, "--- END  of string table---\n");
@@ -1096,24 +1652,24 @@ ocVerifyImage_PEi386 ( ObjectCode* oc )
       if (i >= (Int32)(hdr->NumberOfSymbols)) break;
       symtab_i = (COFF_symbol*)
                  myindex ( sizeof_COFF_symbol, symtab, i );
-      fprintf ( stderr, 
+      fprintf ( stderr,
                 "symbol %d\n"
                 "     name `",
-                i 
+                i
               );
       printName ( symtab_i->Name, strtab );
-      fprintf ( stderr, 
+      fprintf ( stderr,
                 "'\n"
                 "    value 0x%x\n"
-                "     sec# %d\n"
+                "   1+sec# %d\n"
                 "     type 0x%x\n"
                 "   sclass 0x%x\n"
                 "     nAux %d\n",
                 symtab_i->Value,
-                (Int32)(symtab_i->SectionNumber) - 1,
+                (Int32)(symtab_i->SectionNumber),
                 (UInt32)symtab_i->Type,
                 (UInt32)symtab_i->StorageClass,
-                (UInt32)symtab_i->NumberOfAuxSymbols 
+                (UInt32)symtab_i->NumberOfAuxSymbols
               );
       i += symtab_i->NumberOfAuxSymbols;
       i++;
@@ -1135,116 +1691,177 @@ ocGetNames_PEi386 ( ObjectCode* oc )
    UChar* sname;
    void*  addr;
    int    i;
-   
+
    hdr = (COFF_header*)(oc->image);
    sectab = (COFF_section*) (
-               ((UChar*)(oc->image)) 
+               ((UChar*)(oc->image))
                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
             );
    symtab = (COFF_symbol*) (
                ((UChar*)(oc->image))
-               + hdr->PointerToSymbolTable 
+               + hdr->PointerToSymbolTable
             );
    strtab = ((UChar*)(oc->image))
             + hdr->PointerToSymbolTable
             + hdr->NumberOfSymbols * sizeof_COFF_symbol;
 
-   /* Copy exported symbols into the ObjectCode. */
-
-   oc->n_symbols = hdr->NumberOfSymbols;
-   oc->symbols   = stgMallocBytes(oc->n_symbols * sizeof(char*),
-                                  "ocGetNames_PEi386(oc->symbols)");
-   /* Call me paranoid; I don't care. */
-   for (i = 0; i < oc->n_symbols; i++) 
-      oc->symbols[i] = NULL;
-
-   i = 0;
-   while (1) {
-      COFF_symbol* symtab_i;
-      if (i >= (Int32)(hdr->NumberOfSymbols)) break;
-      symtab_i = (COFF_symbol*)
-                 myindex ( sizeof_COFF_symbol, symtab, i );
-
-      if (symtab_i->StorageClass == MYIMAGE_SYM_CLASS_EXTERNAL &&
-          symtab_i->SectionNumber != MYIMAGE_SYM_UNDEFINED) {
-
-         /* This symbol is global and defined, viz, exported */
-         COFF_section* sectabent;
-
-         /* cstring_from_COFF_symbol_name always succeeds. */
-         sname = cstring_from_COFF_symbol_name ( symtab_i->Name, strtab );
+   /* Allocate space for any (local, anonymous) .bss sections. */
 
-         /* for MYIMAGE_SYMCLASS_EXTERNAL 
-                && !MYIMAGE_SYM_UNDEFINED,
-            the address of the symbol is: 
-                address of relevant section + offset in section
-         */
-         sectabent = (COFF_section*)
-                     myindex ( sizeof_COFF_section, 
-                               sectab,
-                               symtab_i->SectionNumber-1 );
-         addr = ((UChar*)(oc->image))
-                + (sectabent->PointerToRawData
-                   + symtab_i->Value);
-         /* fprintf(stderr,"addSymbol %p `%s'\n", addr,sname); */
-         IF_DEBUG(linker, belch("addSymbol %p `%s'\n", addr,sname);)
-         ASSERT(i >= 0 && i < oc->n_symbols);
-         oc->symbols[i] = sname;
-         insertStrHashTable(symhash, sname, addr);
-      }
-      i += symtab_i->NumberOfAuxSymbols;
-      i++;
+   for (i = 0; i < hdr->NumberOfSections; i++) {
+      UChar* zspace;
+      COFF_section* sectab_i
+         = (COFF_section*)
+           myindex ( sizeof_COFF_section, sectab, i );
+      if (0 != strcmp(sectab_i->Name, ".bss")) continue;
+      if (sectab_i->VirtualSize == 0) continue;
+      /* This is a non-empty .bss section.  Allocate zeroed space for
+         it, and set its PointerToRawData field such that oc->image +
+         PointerToRawData == addr_of_zeroed_space.  */
+      zspace = stgCallocBytes(1, sectab_i->VirtualSize,
+                              "ocGetNames_PEi386(anonymous bss)");
+      sectab_i->PointerToRawData = ((UChar*)zspace) - ((UChar*)(oc->image));
+      addProddableBlock(oc, zspace, sectab_i->VirtualSize);
+      /* fprintf(stderr, "BSS anon section at 0x%x\n", zspace); */
    }
 
    /* Copy section information into the ObjectCode. */
 
-   oc->n_sections = hdr->NumberOfSections;
-   oc->sections = stgMallocBytes( oc->n_sections * sizeof(Section), 
-                                  "ocGetNamesPEi386" );
-
-   for (i = 0; i < oc->n_sections; i++) {
+   for (i = 0; i < hdr->NumberOfSections; i++) {
       UChar* start;
       UChar* end;
+      UInt32 sz;
 
-      SectionKind kind 
+      SectionKind kind
          = SECTIONKIND_OTHER;
       COFF_section* sectab_i
          = (COFF_section*)
            myindex ( sizeof_COFF_section, sectab, i );
       IF_DEBUG(linker, belch("section name = %s\n", sectab_i->Name ));
 
-#if 0
-      /* I'm sure this is the Right Way to do it.  However, the 
+#     if 0
+      /* I'm sure this is the Right Way to do it.  However, the
          alternative of testing the sectab_i->Name field seems to
          work ok with Cygwin.
       */
-      if (sectab_i->Characteristics & MYIMAGE_SCN_CNT_CODE || 
+      if (sectab_i->Characteristics & MYIMAGE_SCN_CNT_CODE ||
           sectab_i->Characteristics & MYIMAGE_SCN_CNT_INITIALIZED_DATA)
          kind = SECTIONKIND_CODE_OR_RODATA;
-#endif
+#     endif
 
-      if (0==strcmp(".text",sectab_i->Name))
+      if (0==strcmp(".text",sectab_i->Name) ||
+          0==strcmp(".rodata",sectab_i->Name))
          kind = SECTIONKIND_CODE_OR_RODATA;
       if (0==strcmp(".data",sectab_i->Name) ||
           0==strcmp(".bss",sectab_i->Name))
          kind = SECTIONKIND_RWDATA;
 
-      start = ((UChar*)(oc->image)) 
-              + sectab_i->PointerToRawData;
-      end   = start 
-              + sectab_i->SizeOfRawData - 1;
+      ASSERT(sectab_i->SizeOfRawData == 0 || sectab_i->VirtualSize == 0);
+      sz = sectab_i->SizeOfRawData;
+      if (sz < sectab_i->VirtualSize) sz = sectab_i->VirtualSize;
 
-      if (kind == SECTIONKIND_OTHER) {
+      start = ((UChar*)(oc->image)) + sectab_i->PointerToRawData;
+      end   = start + sz - 1;
+
+      if (kind == SECTIONKIND_OTHER
+          /* Ignore sections called which contain stabs debugging
+             information. */
+          && 0 != strcmp(".stab", sectab_i->Name)
+          && 0 != strcmp(".stabstr", sectab_i->Name)
+         ) {
          belch("Unknown PEi386 section name `%s'", sectab_i->Name);
          return 0;
       }
 
-      oc->sections[i].start = start;
-      oc->sections[i].end   = end;
-      oc->sections[i].kind  = kind;
+      if (kind != SECTIONKIND_OTHER && end >= start) {
+         addSection(oc, kind, start, end);
+         addProddableBlock(oc, start, end - start + 1);
+      }
+   }
+
+   /* Copy exported symbols into the ObjectCode. */
+
+   oc->n_symbols = hdr->NumberOfSymbols;
+   oc->symbols   = stgMallocBytes(oc->n_symbols * sizeof(char*),
+                                  "ocGetNames_PEi386(oc->symbols)");
+   /* Call me paranoid; I don't care. */
+   for (i = 0; i < oc->n_symbols; i++)
+      oc->symbols[i] = NULL;
+
+   i = 0;
+   while (1) {
+      COFF_symbol* symtab_i;
+      if (i >= (Int32)(hdr->NumberOfSymbols)) break;
+      symtab_i = (COFF_symbol*)
+                 myindex ( sizeof_COFF_symbol, symtab, i );
+
+      addr  = NULL;
+
+      if (symtab_i->StorageClass == MYIMAGE_SYM_CLASS_EXTERNAL
+          && symtab_i->SectionNumber != MYIMAGE_SYM_UNDEFINED) {
+         /* This symbol is global and defined, viz, exported */
+         /* for MYIMAGE_SYMCLASS_EXTERNAL
+                && !MYIMAGE_SYM_UNDEFINED,
+            the address of the symbol is:
+                address of relevant section + offset in section
+         */
+         COFF_section* sectabent
+            = (COFF_section*) myindex ( sizeof_COFF_section,
+                                        sectab,
+                                        symtab_i->SectionNumber-1 );
+         addr = ((UChar*)(oc->image))
+                + (sectabent->PointerToRawData
+                   + symtab_i->Value);
+      }
+      else
+      if (symtab_i->SectionNumber == MYIMAGE_SYM_UNDEFINED
+         && symtab_i->Value > 0) {
+         /* This symbol isn't in any section at all, ie, global bss.
+            Allocate zeroed space for it. */
+         addr = stgCallocBytes(1, symtab_i->Value,
+                               "ocGetNames_PEi386(non-anonymous bss)");
+         addSection(oc, SECTIONKIND_RWDATA, addr,
+                        ((UChar*)addr) + symtab_i->Value - 1);
+         addProddableBlock(oc, addr, symtab_i->Value);
+         /* fprintf(stderr, "BSS      section at 0x%x\n", addr); */
+      }
+
+      if (addr != NULL ) {
+         sname = cstring_from_COFF_symbol_name ( symtab_i->Name, strtab );
+         /* fprintf(stderr,"addSymbol %p `%s \n", addr,sname);  */
+         IF_DEBUG(linker, belch("addSymbol %p `%s'\n", addr,sname);)
+         ASSERT(i >= 0 && i < oc->n_symbols);
+         /* cstring_from_COFF_symbol_name always succeeds. */
+         oc->symbols[i] = sname;
+         ghciInsertStrHashTable(oc->fileName, symhash, sname, addr);
+      } else {
+#        if 0
+         fprintf ( stderr,
+                   "IGNORING symbol %d\n"
+                   "     name `",
+                   i
+                 );
+         printName ( symtab_i->Name, strtab );
+         fprintf ( stderr,
+                   "'\n"
+                   "    value 0x%x\n"
+                   "   1+sec# %d\n"
+                   "     type 0x%x\n"
+                   "   sclass 0x%x\n"
+                   "     nAux %d\n",
+                   symtab_i->Value,
+                   (Int32)(symtab_i->SectionNumber),
+                   (UInt32)symtab_i->Type,
+                   (UInt32)symtab_i->StorageClass,
+                   (UInt32)symtab_i->NumberOfAuxSymbols
+                 );
+#        endif
+      }
+
+      i += symtab_i->NumberOfAuxSymbols;
+      i++;
    }
 
-   return 1;   
+   return 1;
 }
 
 
@@ -1260,7 +1877,8 @@ ocResolve_PEi386 ( ObjectCode* oc )
    UInt32        S;
    UInt32*       pP;
 
-   int i, j;
+   int i;
+   UInt32 j, noRelocs;
 
    /* ToDo: should be variable-sized?  But is at least safe in the
       sense of buffer-overrun-proof. */
@@ -1269,12 +1887,12 @@ ocResolve_PEi386 ( ObjectCode* oc )
 
    hdr = (COFF_header*)(oc->image);
    sectab = (COFF_section*) (
-               ((UChar*)(oc->image)) 
+               ((UChar*)(oc->image))
                + sizeof_COFF_header + hdr->SizeOfOptionalHeader
             );
    symtab = (COFF_symbol*) (
                ((UChar*)(oc->image))
-               + hdr->PointerToSymbolTable 
+               + hdr->PointerToSymbolTable
             );
    strtab = ((UChar*)(oc->image))
             + hdr->PointerToSymbolTable
@@ -1288,16 +1906,45 @@ ocResolve_PEi386 ( ObjectCode* oc )
          = (COFF_reloc*) (
               ((UChar*)(oc->image)) + sectab_i->PointerToRelocations
            );
-      for (j = 0; j < sectab_i->NumberOfRelocations; j++) {
+
+      /* Ignore sections called which contain stabs debugging
+         information. */
+      if (0 == strcmp(".stab", sectab_i->Name)
+          || 0 == strcmp(".stabstr", sectab_i->Name))
+         continue;
+
+      if ( sectab_i->Characteristics & MYIMAGE_SCN_LNK_NRELOC_OVFL ) {
+       /* If the relocation field (a short) has overflowed, the
+        * real count can be found in the first reloc entry.
+         *
+        * See Section 4.1 (last para) of the PE spec (rev6.0).
+        *
+        * Nov2003 update: the GNU linker still doesn't correctly 
+        * handle the generation of relocatable object files with 
+        * overflown relocations. Hence the output to warn of potential 
+        * troubles.
+        */
+        COFF_reloc* rel = (COFF_reloc*)
+                           myindex ( sizeof_COFF_reloc, reltab, 0 );
+       noRelocs = rel->VirtualAddress;
+       fprintf(stderr, "WARNING: Overflown relocation field (# relocs found: %u)\n", noRelocs); fflush(stderr);
+       j = 1;
+      } else {
+       noRelocs = sectab_i->NumberOfRelocations;
+        j = 0;
+      }
+
+
+      for (; j < noRelocs; j++) {
          COFF_symbol* sym;
-         COFF_reloc* reltab_j 
+         COFF_reloc* reltab_j
             = (COFF_reloc*)
               myindex ( sizeof_COFF_reloc, reltab, j );
 
          /* the location to patch */
          pP = (UInt32*)(
-                 ((UChar*)(oc->image)) 
-                 + (sectab_i->PointerToRawData 
+                 ((UChar*)(oc->image))
+                 + (sectab_i->PointerToRawData
                     + reltab_j->VirtualAddress
                     - sectab_i->VirtualAddress )
               );
@@ -1305,24 +1952,23 @@ ocResolve_PEi386 ( ObjectCode* oc )
          A = *pP;
          /* the symbol to connect to */
          sym = (COFF_symbol*)
-               myindex ( sizeof_COFF_symbol, 
+               myindex ( sizeof_COFF_symbol,
                          symtab, reltab_j->SymbolTableIndex );
          IF_DEBUG(linker,
-                  fprintf ( stderr, 
+                  fprintf ( stderr,
                             "reloc sec %2d num %3d:  type 0x%-4x   "
                             "vaddr 0x%-8x   name `",
                             i, j,
-                            (UInt32)reltab_j->Type, 
+                            (UInt32)reltab_j->Type,
                             reltab_j->VirtualAddress );
                             printName ( sym->Name, strtab );
                             fprintf ( stderr, "'\n" ));
 
          if (sym->StorageClass == MYIMAGE_SYM_CLASS_STATIC) {
-            COFF_section* section_sym 
+            COFF_section* section_sym
                = findPEi386SectionCalled ( oc, sym->Name );
             if (!section_sym) {
-               fprintf ( stderr, "bad section = `%s'\n", sym->Name );
-               barf("Can't find abovementioned PEi386 section");
+               belch("%s: can't find section `%s'", oc->fileName, sym->Name);
                return 0;
             }
             S = ((UInt32)(oc->image))
@@ -1330,20 +1976,24 @@ ocResolve_PEi386 ( ObjectCode* oc )
                    + sym->Value);
          } else {
             copyName ( sym->Name, strtab, symbol, 1000-1 );
+            (void*)S = lookupLocalSymbol( oc, symbol );
+            if ((void*)S != NULL) goto foundit;
+            (void*)S = lookupSymbol( symbol );
+            if ((void*)S != NULL) goto foundit;
             zapTrailingAtSign ( symbol );
             (void*)S = lookupLocalSymbol( oc, symbol );
-            if ((void*)S == NULL)
-               (void*)S = lookupSymbol( symbol );
-            if (S == 0) {
-               belch("ocResolve_PEi386: %s: unknown symbol `%s'", 
-                      oc->fileName, symbol);
-               return 0;
-            }
+            if ((void*)S != NULL) goto foundit;
+            (void*)S = lookupSymbol( symbol );
+            if ((void*)S != NULL) goto foundit;
+           /* Newline first because the interactive linker has printed "linking..." */
+            belch("\n%s: unknown symbol `%s'", oc->fileName, symbol);
+            return 0;
+           foundit:
          }
-
+         checkProddableBlock(oc, pP);
          switch (reltab_j->Type) {
-            case MYIMAGE_REL_I386_DIR32: 
-               *pP = A + S; 
+            case MYIMAGE_REL_I386_DIR32:
+               *pP = A + S;
                break;
             case MYIMAGE_REL_I386_REL32:
                /* Tricky.  We have to insert a displacement at
@@ -1360,18 +2010,16 @@ ocResolve_PEi386 ( ObjectCode* oc )
                ASSERT(A==0);
                *pP = S - ((UInt32)pP) - 4;
                break;
-            default: 
-               fprintf(stderr, 
-                       "unhandled PEi386 relocation type %d\n",
-                       reltab_j->Type);
-               barf("unhandled PEi386 relocation type");
+            default:
+               belch("%s: unhandled PEi386 relocation type %d",
+                    oc->fileName, reltab_j->Type);
                return 0;
          }
 
       }
    }
-   
-   /* fprintf(stderr, "completed     %s\n", oc->fileName); */
+
+   IF_DEBUG(linker, belch("completed %s", oc->fileName));
    return 1;
 }
 
@@ -1389,21 +2037,215 @@ ocResolve_PEi386 ( ObjectCode* oc )
 
 #if defined(sparc_TARGET_ARCH)
 #  define ELF_TARGET_SPARC  /* Used inside <elf.h> */
+#elif defined(i386_TARGET_ARCH)
+#  define ELF_TARGET_386    /* Used inside <elf.h> */
+#elif defined(x86_64_TARGET_ARCH)
+#  define ELF_TARGET_X64_64
+#  define ELF_64BIT
+#elif defined (ia64_TARGET_ARCH)
+#  define ELF_TARGET_IA64   /* Used inside <elf.h> */
+#  define ELF_64BIT
+#  define ELF_FUNCTION_DESC /* calling convention uses function descriptors */
+#  define ELF_NEED_GOT      /* needs Global Offset Table */
+#  define ELF_NEED_PLT      /* needs Procedure Linkage Tables */
 #endif
 
+#if !defined(openbsd_TARGET_OS)
 #include <elf.h>
+#else
+/* openbsd elf has things in different places, with diff names */
+#include <elf_abi.h>
+#include <machine/reloc.h>
+#define R_386_32    RELOC_32
+#define R_386_PC32  RELOC_PC32
+#endif
+
+/*
+ * Define a set of types which can be used for both ELF32 and ELF64
+ */
+
+#ifdef ELF_64BIT
+#define ELFCLASS    ELFCLASS64
+#define Elf_Addr    Elf64_Addr
+#define Elf_Word    Elf64_Word
+#define Elf_Sword   Elf64_Sword
+#define Elf_Ehdr    Elf64_Ehdr
+#define Elf_Phdr    Elf64_Phdr
+#define Elf_Shdr    Elf64_Shdr
+#define Elf_Sym     Elf64_Sym
+#define Elf_Rel     Elf64_Rel
+#define Elf_Rela    Elf64_Rela
+#define ELF_ST_TYPE ELF64_ST_TYPE
+#define ELF_ST_BIND ELF64_ST_BIND
+#define ELF_R_TYPE  ELF64_R_TYPE
+#define ELF_R_SYM   ELF64_R_SYM
+#else
+#define ELFCLASS    ELFCLASS32
+#define Elf_Addr    Elf32_Addr
+#define Elf_Word    Elf32_Word
+#define Elf_Sword   Elf32_Sword
+#define Elf_Ehdr    Elf32_Ehdr
+#define Elf_Phdr    Elf32_Phdr
+#define Elf_Shdr    Elf32_Shdr
+#define Elf_Sym     Elf32_Sym
+#define Elf_Rel     Elf32_Rel
+#define Elf_Rela    Elf32_Rela
+#ifndef ELF_ST_TYPE
+#define ELF_ST_TYPE ELF32_ST_TYPE
+#endif
+#ifndef ELF_ST_BIND
+#define ELF_ST_BIND ELF32_ST_BIND
+#endif
+#ifndef ELF_R_TYPE
+#define ELF_R_TYPE  ELF32_R_TYPE
+#endif
+#ifndef ELF_R_SYM
+#define ELF_R_SYM   ELF32_R_SYM
+#endif
+#endif
+
+
+/*
+ * Functions to allocate entries in dynamic sections.  Currently we simply
+ * preallocate a large number, and we don't check if a entry for the given
+ * target already exists (a linear search is too slow).  Ideally these
+ * entries would be associated with symbols.
+ */
+
+/* These sizes sufficient to load HSbase + HShaskell98 + a few modules */
+#define GOT_SIZE            0x20000
+#define FUNCTION_TABLE_SIZE 0x10000
+#define PLT_SIZE            0x08000
+
+#ifdef ELF_NEED_GOT
+static Elf_Addr got[GOT_SIZE];
+static unsigned int gotIndex;
+static Elf_Addr gp_val = (Elf_Addr)got;
+
+static Elf_Addr
+allocateGOTEntry(Elf_Addr target)
+{
+   Elf_Addr *entry;
+
+   if (gotIndex >= GOT_SIZE)
+      barf("Global offset table overflow");
+
+   entry = &got[gotIndex++];
+   *entry = target;
+   return (Elf_Addr)entry;
+}
+#endif
+
+#ifdef ELF_FUNCTION_DESC
+typedef struct {
+   Elf_Addr ip;
+   Elf_Addr gp;
+} FunctionDesc;
+
+static FunctionDesc functionTable[FUNCTION_TABLE_SIZE];
+static unsigned int functionTableIndex;
+
+static Elf_Addr
+allocateFunctionDesc(Elf_Addr target)
+{
+   FunctionDesc *entry;
+
+   if (functionTableIndex >= FUNCTION_TABLE_SIZE)
+      barf("Function table overflow");
+
+   entry = &functionTable[functionTableIndex++];
+   entry->ip = target;
+   entry->gp = (Elf_Addr)gp_val;
+   return (Elf_Addr)entry;
+}
+
+static Elf_Addr
+copyFunctionDesc(Elf_Addr target)
+{
+   FunctionDesc *olddesc = (FunctionDesc *)target;
+   FunctionDesc *newdesc;
+
+   newdesc = (FunctionDesc *)allocateFunctionDesc(olddesc->ip);
+   newdesc->gp = olddesc->gp;
+   return (Elf_Addr)newdesc;
+}
+#endif
+
+#ifdef ELF_NEED_PLT
+#ifdef ia64_TARGET_ARCH
+static void ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value);
+static void ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc);
+
+static unsigned char plt_code[] =
+{
+   /* taken from binutils bfd/elfxx-ia64.c */
+   0x0b, 0x78, 0x00, 0x02, 0x00, 0x24,  /*   [MMI]       addl r15=0,r1;;    */
+   0x00, 0x41, 0x3c, 0x30, 0x28, 0xc0,  /*               ld8 r16=[r15],8    */
+   0x01, 0x08, 0x00, 0x84,              /*               mov r14=r1;;       */
+   0x11, 0x08, 0x00, 0x1e, 0x18, 0x10,  /*   [MIB]       ld8 r1=[r15]       */
+   0x60, 0x80, 0x04, 0x80, 0x03, 0x00,  /*               mov b6=r16         */
+   0x60, 0x00, 0x80, 0x00               /*               br.few b6;;        */
+};
+
+/* If we can't get to the function descriptor via gp, take a local copy of it */
+#define PLT_RELOC(code, target) { \
+   Elf64_Sxword rel_value = target - gp_val; \
+   if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff)) \
+      ia64_reloc_gprel22((Elf_Addr)code, copyFunctionDesc(target)); \
+   else \
+      ia64_reloc_gprel22((Elf_Addr)code, target); \
+   }
+#endif
+
+typedef struct {
+   unsigned char code[sizeof(plt_code)];
+} PLTEntry;
+
+static Elf_Addr
+allocatePLTEntry(Elf_Addr target, ObjectCode *oc)
+{
+   PLTEntry *plt = (PLTEntry *)oc->plt;
+   PLTEntry *entry;
+
+   if (oc->pltIndex >= PLT_SIZE)
+      barf("Procedure table overflow");
+
+   entry = &plt[oc->pltIndex++];
+   memcpy(entry->code, plt_code, sizeof(entry->code));
+   PLT_RELOC(entry->code, target);
+   return (Elf_Addr)entry;
+}
+
+static unsigned int
+PLTSize(void)
+{
+   return (PLT_SIZE * sizeof(PLTEntry));
+}
+#endif
+
+
+/*
+ * Generic ELF functions
+ */
 
 static char *
-findElfSection ( void* objImage, Elf32_Word sh_type )
+findElfSection ( void* objImage, Elf_Word sh_type )
 {
-   int i;
    char* ehdrC = (char*)objImage;
-   Elf32_Ehdr* ehdr = ( Elf32_Ehdr*)ehdrC;
-   Elf32_Shdr* shdr = (Elf32_Shdr*) (ehdrC + ehdr->e_shoff);
+   Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
+   Elf_Shdr* shdr = (Elf_Shdr*)(ehdrC + ehdr->e_shoff);
+   char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
    char* ptr = NULL;
+   int i;
+
    for (i = 0; i < ehdr->e_shnum; i++) {
-      if (shdr[i].sh_type == sh_type &&
-          i !=  ehdr->e_shstrndx) {
+      if (shdr[i].sh_type == sh_type
+          /* Ignore the section header's string table. */
+          && i != ehdr->e_shstrndx
+         /* Ignore string tables named .stabstr, as they contain
+             debugging info. */
+          && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
+         ) {
          ptr = ehdrC + shdr[i].sh_offset;
          break;
       }
@@ -1411,47 +2253,62 @@ findElfSection ( void* objImage, Elf32_Word sh_type )
    return ptr;
 }
 
+#if defined(ia64_TARGET_ARCH)
+static Elf_Addr
+findElfSegment ( void* objImage, Elf_Addr vaddr )
+{
+   char* ehdrC = (char*)objImage;
+   Elf_Ehdr* ehdr = (Elf_Ehdr*)ehdrC;
+   Elf_Phdr* phdr = (Elf_Phdr*)(ehdrC + ehdr->e_phoff);
+   Elf_Addr segaddr = 0;
+   int i;
+
+   for (i = 0; i < ehdr->e_phnum; i++) {
+      segaddr = phdr[i].p_vaddr;
+      if ((vaddr >= segaddr) && (vaddr < segaddr + phdr[i].p_memsz))
+             break;
+   }
+   return segaddr;
+}
+#endif
 
 static int
 ocVerifyImage_ELF ( ObjectCode* oc )
 {
-   Elf32_Shdr* shdr;
-   Elf32_Sym*  stab;
+   Elf_Shdr* shdr;
+   Elf_Sym*  stab;
    int i, j, nent, nstrtab, nsymtabs;
    char* sh_strtab;
    char* strtab;
 
-   char*       ehdrC = (char*)(oc->image);
-   Elf32_Ehdr* ehdr  = ( Elf32_Ehdr*)ehdrC;
+   char*     ehdrC = (char*)(oc->image);
+   Elf_Ehdr* ehdr  = (Elf_Ehdr*)ehdrC;
 
    if (ehdr->e_ident[EI_MAG0] != ELFMAG0 ||
        ehdr->e_ident[EI_MAG1] != ELFMAG1 ||
        ehdr->e_ident[EI_MAG2] != ELFMAG2 ||
        ehdr->e_ident[EI_MAG3] != ELFMAG3) {
-      belch("ocVerifyImage_ELF: not an ELF header");
+      belch("%s: not an ELF object", oc->fileName);
       return 0;
    }
-   IF_DEBUG(linker,belch( "Is an ELF header" ));
 
-   if (ehdr->e_ident[EI_CLASS] != ELFCLASS32) {
-      belch("ocVerifyImage_ELF: not 32 bit ELF" );
+   if (ehdr->e_ident[EI_CLASS] != ELFCLASS) {
+      belch("%s: unsupported ELF format", oc->fileName);
       return 0;
    }
 
-   IF_DEBUG(linker,belch( "Is 32 bit ELF" ));
-
    if (ehdr->e_ident[EI_DATA] == ELFDATA2LSB) {
        IF_DEBUG(linker,belch( "Is little-endian" ));
    } else
    if (ehdr->e_ident[EI_DATA] == ELFDATA2MSB) {
        IF_DEBUG(linker,belch( "Is big-endian" ));
    } else {
-       belch("ocVerifyImage_ELF: unknown endiannness");
+       belch("%s: unknown endiannness", oc->fileName);
        return 0;
    }
 
    if (ehdr->e_type != ET_REL) {
-      belch("ocVerifyImage_ELF: not a relocatable object (.o) file");
+      belch("%s: not a relocatable object (.o) file", oc->fileName);
       return 0;
    }
    IF_DEBUG(linker, belch( "Is a relocatable object (.o) file" ));
@@ -1460,24 +2317,27 @@ ocVerifyImage_ELF ( ObjectCode* oc )
    switch (ehdr->e_machine) {
       case EM_386:   IF_DEBUG(linker,belch( "x86" )); break;
       case EM_SPARC: IF_DEBUG(linker,belch( "sparc" )); break;
-      default:       IF_DEBUG(linker,belch( "unknown" )); 
-                     belch("ocVerifyImage_ELF: unknown architecture");
+#ifdef EM_IA_64
+      case EM_IA_64: IF_DEBUG(linker,belch( "ia64" )); break;
+#endif
+      default:       IF_DEBUG(linker,belch( "unknown" ));
+                     belch("%s: unknown architecture", oc->fileName);
                      return 0;
    }
 
    IF_DEBUG(linker,belch(
-             "\nSection header table: start %d, n_entries %d, ent_size %d", 
+             "\nSection header table: start %d, n_entries %d, ent_size %d",
              ehdr->e_shoff, ehdr->e_shnum, ehdr->e_shentsize  ));
 
-   ASSERT (ehdr->e_shentsize == sizeof(Elf32_Shdr));
+   ASSERT (ehdr->e_shentsize == sizeof(Elf_Shdr));
 
-   shdr = (Elf32_Shdr*) (ehdrC + ehdr->e_shoff);
+   shdr = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
 
    if (ehdr->e_shstrndx == SHN_UNDEF) {
-      belch("ocVerifyImage_ELF: no section header string table");
+      belch("%s: no section header string table", oc->fileName);
       return 0;
    } else {
-      IF_DEBUG(linker,belch( "Section header string table is section %d", 
+      IF_DEBUG(linker,belch( "Section header string table is section %d",
                           ehdr->e_shstrndx));
       sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
    }
@@ -1488,7 +2348,7 @@ ocVerifyImage_ELF ( ObjectCode* oc )
       IF_DEBUG(linker,fprintf(stderr, "size=%4d  ", (int)shdr[i].sh_size ));
       IF_DEBUG(linker,fprintf(stderr, "offs=%4d  ", (int)shdr[i].sh_offset ));
       IF_DEBUG(linker,fprintf(stderr, "  (%p .. %p)  ",
-               ehdrC + shdr[i].sh_offset, 
+               ehdrC + shdr[i].sh_offset,
                      ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1));
 
       if (shdr[i].sh_type == SHT_REL) {
@@ -1507,43 +2367,48 @@ ocVerifyImage_ELF ( ObjectCode* oc )
    strtab = NULL;
    nstrtab = 0;
    for (i = 0; i < ehdr->e_shnum; i++) {
-      if (shdr[i].sh_type == SHT_STRTAB &&
-          i !=  ehdr->e_shstrndx) {
-         IF_DEBUG(linker,belch("   section %d is a normal string table", i ));
+      if (shdr[i].sh_type == SHT_STRTAB
+          /* Ignore the section header's string table. */
+          && i != ehdr->e_shstrndx
+         /* Ignore string tables named .stabstr, as they contain
+             debugging info. */
+          && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
+         ) {
+         IF_DEBUG(linker,belch("   section %d is a normal string table", i ));
          strtab = ehdrC + shdr[i].sh_offset;
          nstrtab++;
       }
-   }  
+   }
    if (nstrtab != 1) {
-      belch("ocVerifyImage_ELF: no string tables, or too many");
+      belch("%s: no string tables, or too many", oc->fileName);
       return 0;
    }
 
    nsymtabs = 0;
-   IF_DEBUG(linker,belch( "\nSymbol tables" )); 
+   IF_DEBUG(linker,belch( "\nSymbol tables" ));
    for (i = 0; i < ehdr->e_shnum; i++) {
       if (shdr[i].sh_type != SHT_SYMTAB) continue;
       IF_DEBUG(linker,belch( "section %d is a symbol table", i ));
       nsymtabs++;
-      stab = (Elf32_Sym*) (ehdrC + shdr[i].sh_offset);
-      nent = shdr[i].sh_size / sizeof(Elf32_Sym);
+      stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
+      nent = shdr[i].sh_size / sizeof(Elf_Sym);
       IF_DEBUG(linker,belch( "   number of entries is apparently %d (%d rem)",
                nent,
-               shdr[i].sh_size % sizeof(Elf32_Sym)
+               shdr[i].sh_size % sizeof(Elf_Sym)
              ));
-      if (0 != shdr[i].sh_size % sizeof(Elf32_Sym)) {
-         belch("ocVerifyImage_ELF: non-integral number of symbol table entries");
+      if (0 != shdr[i].sh_size % sizeof(Elf_Sym)) {
+         belch("%s: non-integral number of symbol table entries", oc->fileName);
          return 0;
       }
       for (j = 0; j < nent; j++) {
          IF_DEBUG(linker,fprintf(stderr, "   %2d  ", j ));
-         IF_DEBUG(linker,fprintf(stderr, "  sec=%-5d  size=%-3d  val=%5p  ", 
+         IF_DEBUG(linker,fprintf(stderr, "  sec=%-5d  size=%-3d  val=%5p  ",
                              (int)stab[j].st_shndx,
                              (int)stab[j].st_size,
                              (char*)stab[j].st_value ));
 
          IF_DEBUG(linker,fprintf(stderr, "type=" ));
-         switch (ELF32_ST_TYPE(stab[j].st_info)) {
+         switch (ELF_ST_TYPE(stab[j].st_info)) {
             case STT_NOTYPE:  IF_DEBUG(linker,fprintf(stderr, "notype " )); break;
             case STT_OBJECT:  IF_DEBUG(linker,fprintf(stderr, "object " )); break;
             case STT_FUNC  :  IF_DEBUG(linker,fprintf(stderr, "func   " )); break;
@@ -1554,7 +2419,7 @@ ocVerifyImage_ELF ( ObjectCode* oc )
          IF_DEBUG(linker,fprintf(stderr, "  " ));
 
          IF_DEBUG(linker,fprintf(stderr, "bind=" ));
-         switch (ELF32_ST_BIND(stab[j].st_info)) {
+         switch (ELF_ST_BIND(stab[j].st_info)) {
             case STB_LOCAL :  IF_DEBUG(linker,fprintf(stderr, "local " )); break;
             case STB_GLOBAL:  IF_DEBUG(linker,fprintf(stderr, "global" )); break;
             case STB_WEAK  :  IF_DEBUG(linker,fprintf(stderr, "weak  " )); break;
@@ -1567,7 +2432,7 @@ ocVerifyImage_ELF ( ObjectCode* oc )
    }
 
    if (nsymtabs == 0) {
-      belch("ocVerifyImage_ELF: didn't find any symbol tables");
+      belch("%s: didn't find any symbol tables", oc->fileName);
       return 0;
    }
 
@@ -1579,56 +2444,107 @@ static int
 ocGetNames_ELF ( ObjectCode* oc )
 {
    int i, j, k, nent;
-   Elf32_Sym* stab;
+   Elf_Sym* stab;
 
-   char*       ehdrC      = (char*)(oc->image);
-   Elf32_Ehdr* ehdr       = (Elf32_Ehdr*)ehdrC;
-   char*       strtab     = findElfSection ( ehdrC, SHT_STRTAB );
-   Elf32_Shdr* shdr       = (Elf32_Shdr*) (ehdrC + ehdr->e_shoff);
-   char*       sh_strtab  = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
+   char*     ehdrC    = (char*)(oc->image);
+   Elf_Ehdr* ehdr     = (Elf_Ehdr*)ehdrC;
+   char*     strtab   = findElfSection ( ehdrC, SHT_STRTAB );
+   Elf_Shdr* shdr     = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
 
    ASSERT(symhash != NULL);
 
    if (!strtab) {
-      belch("ocGetNames_ELF: no strtab");
+      belch("%s: no strtab", oc->fileName);
       return 0;
    }
 
    k = 0;
-   oc->n_sections = ehdr->e_shnum;
-   oc->sections = stgMallocBytes( oc->n_sections * sizeof(Section), 
-                                  "ocGetNames_ELF(oc->sections)" );
-
-   for (i = 0; i < oc->n_sections; i++) {
-
-      /* make a section entry for relevant sections */
-      SectionKind kind = SECTIONKIND_OTHER;
-      if (!strcmp(".data",sh_strtab+shdr[i].sh_name) ||
-          !strcmp(".data1",sh_strtab+shdr[i].sh_name))
-         kind = SECTIONKIND_RWDATA;
-      if (!strcmp(".text",sh_strtab+shdr[i].sh_name) ||
-          !strcmp(".rodata",sh_strtab+shdr[i].sh_name) ||
-          !strcmp(".rodata1",sh_strtab+shdr[i].sh_name))
-         kind = SECTIONKIND_CODE_OR_RODATA;
+   for (i = 0; i < ehdr->e_shnum; i++) {
+      /* Figure out what kind of section it is.  Logic derived from
+         Figure 1.14 ("Special Sections") of the ELF document
+         ("Portable Formats Specification, Version 1.1"). */
+      Elf_Shdr    hdr    = shdr[i];
+      SectionKind kind   = SECTIONKIND_OTHER;
+      int         is_bss = FALSE;
+
+      if (hdr.sh_type == SHT_PROGBITS
+          && (hdr.sh_flags & SHF_ALLOC) && (hdr.sh_flags & SHF_EXECINSTR)) {
+         /* .text-style section */
+         kind = SECTIONKIND_CODE_OR_RODATA;
+      }
+      else
+      if (hdr.sh_type == SHT_PROGBITS
+          && (hdr.sh_flags & SHF_ALLOC) && (hdr.sh_flags & SHF_WRITE)) {
+         /* .data-style section */
+         kind = SECTIONKIND_RWDATA;
+      }
+      else
+      if (hdr.sh_type == SHT_PROGBITS
+          && (hdr.sh_flags & SHF_ALLOC) && !(hdr.sh_flags & SHF_WRITE)) {
+         /* .rodata-style section */
+         kind = SECTIONKIND_CODE_OR_RODATA;
+      }
+      else
+      if (hdr.sh_type == SHT_NOBITS
+          && (hdr.sh_flags & SHF_ALLOC) && (hdr.sh_flags & SHF_WRITE)) {
+         /* .bss-style section */
+         kind = SECTIONKIND_RWDATA;
+         is_bss = TRUE;
+      }
+
+      if (is_bss && shdr[i].sh_size > 0) {
+         /* This is a non-empty .bss section.  Allocate zeroed space for
+            it, and set its .sh_offset field such that
+            ehdrC + .sh_offset == addr_of_zeroed_space.  */
+         char* zspace = stgCallocBytes(1, shdr[i].sh_size,
+                                       "ocGetNames_ELF(BSS)");
+         shdr[i].sh_offset = ((char*)zspace) - ((char*)ehdrC);
+        /*
+         fprintf(stderr, "BSS section at 0x%x, size %d\n",
+                         zspace, shdr[i].sh_size);
+        */
+      }
 
       /* fill in the section info */
-      oc->sections[i].start = ehdrC + shdr[i].sh_offset;
-      oc->sections[i].end   = ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1;
-      oc->sections[i].kind  = kind;
-      
+      if (kind != SECTIONKIND_OTHER && shdr[i].sh_size > 0) {
+         addProddableBlock(oc, ehdrC + shdr[i].sh_offset, shdr[i].sh_size);
+         addSection(oc, kind, ehdrC + shdr[i].sh_offset,
+                        ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1);
+      }
+
       if (shdr[i].sh_type != SHT_SYMTAB) continue;
 
       /* copy stuff into this module's object symbol table */
-      stab = (Elf32_Sym*) (ehdrC + shdr[i].sh_offset);
-      nent = shdr[i].sh_size / sizeof(Elf32_Sym);
+      stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
+      nent = shdr[i].sh_size / sizeof(Elf_Sym);
 
       oc->n_symbols = nent;
-      oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*), 
+      oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
                                    "ocGetNames_ELF(oc->symbols)");
 
       for (j = 0; j < nent; j++) {
-         if ( ( ELF32_ST_BIND(stab[j].st_info)==STB_GLOBAL
-                || ELF32_ST_BIND(stab[j].st_info)==STB_LOCAL
+
+         char  isLocal = FALSE; /* avoids uninit-var warning */
+         char* ad      = NULL;
+         char* nm      = strtab + stab[j].st_name;
+         int   secno   = stab[j].st_shndx;
+
+        /* Figure out if we want to add it; if so, set ad to its
+            address.  Otherwise leave ad == NULL. */
+
+         if (secno == SHN_COMMON) {
+            isLocal = FALSE;
+            ad = stgCallocBytes(1, stab[j].st_size, "ocGetNames_ELF(COMMON)");
+           /*
+            fprintf(stderr, "COMMON symbol, size %d name %s\n",
+                            stab[j].st_size, nm);
+           */
+           /* Pointless to do addProddableBlock() for this area,
+               since the linker should never poke around in it. */
+        }
+         else
+         if ( ( ELF_ST_BIND(stab[j].st_info)==STB_GLOBAL
+                || ELF_ST_BIND(stab[j].st_info)==STB_LOCAL
               )
               /* and not an undefined symbol */
               && stab[j].st_shndx != SHN_UNDEF
@@ -1636,112 +2552,141 @@ ocGetNames_ELF ( ObjectCode* oc )
               && stab[j].st_shndx < SHN_LORESERVE
               &&
              /* and it's a not a section or string table or anything silly */
-              ( ELF32_ST_TYPE(stab[j].st_info)==STT_FUNC ||
-                ELF32_ST_TYPE(stab[j].st_info)==STT_OBJECT ||
-                ELF32_ST_TYPE(stab[j].st_info)==STT_NOTYPE 
+              ( ELF_ST_TYPE(stab[j].st_info)==STT_FUNC ||
+                ELF_ST_TYPE(stab[j].st_info)==STT_OBJECT ||
+                ELF_ST_TYPE(stab[j].st_info)==STT_NOTYPE
               )
-            ) { 
-            char* nm = strtab + stab[j].st_name;
-            char* ad = ehdrC 
-                       + shdr[ stab[j].st_shndx ].sh_offset
-                       + stab[j].st_value;
-            ASSERT(nm != NULL);
-            ASSERT(ad != NULL);
-           oc->symbols[j] = nm;
-            if (ELF32_ST_BIND(stab[j].st_info)==STB_LOCAL) {
-               IF_DEBUG(linker,belch( "addOTabName(LOCL): %10p  %s %s",
-                                      ad, oc->fileName, nm ));
-               insertStrHashTable(oc->lochash, nm, ad);
+            ) {
+           /* Section 0 is the undefined section, hence > and not >=. */
+            ASSERT(secno > 0 && secno < ehdr->e_shnum);
+           /*
+            if (shdr[secno].sh_type == SHT_NOBITS) {
+               fprintf(stderr, "   BSS symbol, size %d off %d name %s\n",
+                               stab[j].st_size, stab[j].st_value, nm);
+            }
+            */
+            ad = ehdrC + shdr[ secno ].sh_offset + stab[j].st_value;
+            if (ELF_ST_BIND(stab[j].st_info)==STB_LOCAL) {
+               isLocal = TRUE;
             } else {
+#ifdef ELF_FUNCTION_DESC
+               /* dlsym() and the initialisation table both give us function
+               * descriptors, so to be consistent we store function descriptors
+               * in the symbol table */
+               if (ELF_ST_TYPE(stab[j].st_info) == STT_FUNC)
+                   ad = (char *)allocateFunctionDesc((Elf_Addr)ad);
+#endif
                IF_DEBUG(linker,belch( "addOTabName(GLOB): %10p  %s %s",
                                       ad, oc->fileName, nm ));
-               insertStrHashTable(symhash, nm, ad);
+               isLocal = FALSE;
             }
          }
-         else {
-            IF_DEBUG(linker,belch( "skipping `%s'", 
+
+         /* And the decision is ... */
+
+         if (ad != NULL) {
+            ASSERT(nm != NULL);
+           oc->symbols[j] = nm;
+            /* Acquire! */
+            if (isLocal) {
+               /* Ignore entirely. */
+            } else {
+               ghciInsertStrHashTable(oc->fileName, symhash, nm, ad);
+            }
+         } else {
+            /* Skip. */
+            IF_DEBUG(linker,belch( "skipping `%s'",
                                    strtab + stab[j].st_name ));
             /*
-            fprintf(stderr, 
+            fprintf(stderr,
                     "skipping   bind = %d,  type = %d,  shndx = %d   `%s'\n",
-                    (int)ELF32_ST_BIND(stab[j].st_info), 
-                    (int)ELF32_ST_TYPE(stab[j].st_info), 
+                    (int)ELF_ST_BIND(stab[j].st_info),
+                    (int)ELF_ST_TYPE(stab[j].st_info),
                     (int)stab[j].st_shndx,
                     strtab + stab[j].st_name
                    );
             */
             oc->symbols[j] = NULL;
          }
+
       }
    }
 
    return 1;
 }
 
-
 /* Do ELF relocations which lack an explicit addend.  All x86-linux
    relocations appear to be of this form. */
-static int do_Elf32_Rel_relocations ( ObjectCode* oc, char* ehdrC,
-                                      Elf32_Shdr* shdr, int shnum, 
-                                      Elf32_Sym*  stab, char* strtab )
+static int
+do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
+                         Elf_Shdr* shdr, int shnum,
+                         Elf_Sym*  stab, char* strtab )
 {
    int j;
    char *symbol;
-   Elf32_Word* targ;
-   Elf32_Rel*  rtab = (Elf32_Rel*) (ehdrC + shdr[shnum].sh_offset);
-   int         nent = shdr[shnum].sh_size / sizeof(Elf32_Rel);
+   Elf_Word* targ;
+   Elf_Rel*  rtab = (Elf_Rel*) (ehdrC + shdr[shnum].sh_offset);
+   int         nent = shdr[shnum].sh_size / sizeof(Elf_Rel);
    int target_shndx = shdr[shnum].sh_info;
    int symtab_shndx = shdr[shnum].sh_link;
-   stab  = (Elf32_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
-   targ  = (Elf32_Word*)(ehdrC + shdr[ target_shndx ].sh_offset);
+
+   stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
+   targ  = (Elf_Word*)(ehdrC + shdr[ target_shndx ].sh_offset);
    IF_DEBUG(linker,belch( "relocations for section %d using symtab %d",
                           target_shndx, symtab_shndx ));
+
    for (j = 0; j < nent; j++) {
-      Elf32_Addr offset = rtab[j].r_offset;
-      Elf32_Word info   = rtab[j].r_info;
+      Elf_Addr offset = rtab[j].r_offset;
+      Elf_Addr info   = rtab[j].r_info;
 
-      Elf32_Addr  P  = ((Elf32_Addr)targ) + offset;
-      Elf32_Word* pP = (Elf32_Word*)P;
-      Elf32_Addr  A  = *pP;
-      Elf32_Addr  S;
+      Elf_Addr  P  = ((Elf_Addr)targ) + offset;
+      Elf_Word* pP = (Elf_Word*)P;
+      Elf_Addr  A  = *pP;
+      Elf_Addr  S;
+      Elf_Addr  value;
 
-      IF_DEBUG(linker,belch( "Rel entry %3d is raw(%6p %6p)", 
+      IF_DEBUG(linker,belch( "Rel entry %3d is raw(%6p %6p)",
                              j, (void*)offset, (void*)info ));
       if (!info) {
          IF_DEBUG(linker,belch( " ZERO" ));
          S = 0;
       } else {
-         /* First see if it is a nameless local symbol. */
-         if (stab[ ELF32_R_SYM(info)].st_name == 0) {
-            symbol = "(noname)";
-            S = (Elf32_Addr)
-                (ehdrC + shdr[stab[ELF32_R_SYM(info)].st_shndx ].sh_offset
-                       + stab[ELF32_R_SYM(info)].st_value);
-         } else {
-            /* No?  Should be in a symbol table then; first try the
-               local one. */
-            symbol = strtab+stab[ ELF32_R_SYM(info)].st_name;
-            (void*)S = lookupLocalSymbol( oc, symbol );
-            if ((void*)S == NULL)
-               (void*)S = lookupSymbol( symbol );
-         }
+         Elf_Sym sym = stab[ELF_R_SYM(info)];
+        /* First see if it is a local symbol. */
+         if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
+            /* Yes, so we can get the address directly from the ELF symbol
+               table. */
+            symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
+            S = (Elf_Addr)
+                (ehdrC + shdr[ sym.st_shndx ].sh_offset
+                       + stab[ELF_R_SYM(info)].st_value);
+
+        } else {
+            /* No, so look up the name in our global table. */
+            symbol = strtab + sym.st_name;
+            (void*)S = lookupSymbol( symbol );
+        }
          if (!S) {
-            barf("do_Elf32_Rel_relocations:  %s: unknown symbol `%s'", 
-                 oc->fileName, symbol);
+            belch("%s: unknown symbol `%s'", oc->fileName, symbol);
+           return 0;
          }
          IF_DEBUG(linker,belch( "`%s' resolves to %p", symbol, (void*)S ));
       }
+
       IF_DEBUG(linker,belch( "Reloc: P = %p   S = %p   A = %p",
-                            (void*)P, (void*)S, (void*)A )); 
-      switch (ELF32_R_TYPE(info)) {
+                            (void*)P, (void*)S, (void*)A ));
+      checkProddableBlock ( oc, pP );
+
+      value = S + A;
+
+      switch (ELF_R_TYPE(info)) {
 #        ifdef i386_TARGET_ARCH
-         case R_386_32:   *pP = S + A;     break;
-         case R_386_PC32: *pP = S + A - P; break;
+         case R_386_32:   *pP = value;     break;
+         case R_386_PC32: *pP = value - P; break;
 #        endif
-         default: 
-            fprintf(stderr, "unhandled ELF relocation(Rel) type %d\n",
-                            ELF32_R_TYPE(info));
-            barf("do_Elf32_Rel_relocations: unhandled ELF relocation type");
+         default:
+            belch("%s: unhandled ELF relocation(Rel) type %d\n",
+                 oc->fileName, ELF_R_TYPE(info));
             return 0;
       }
 
@@ -1749,103 +2694,162 @@ static int do_Elf32_Rel_relocations ( ObjectCode* oc, char* ehdrC,
    return 1;
 }
 
-
 /* Do ELF relocations for which explicit addends are supplied.
    sparc-solaris relocations appear to be of this form. */
-static int do_Elf32_Rela_relocations ( ObjectCode* oc, char* ehdrC,
-                                       Elf32_Shdr* shdr, int shnum, 
-                                       Elf32_Sym*  stab, char* strtab )
+static int
+do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
+                          Elf_Shdr* shdr, int shnum,
+                          Elf_Sym*  stab, char* strtab )
 {
    int j;
    char *symbol;
-   Elf32_Word* targ;
-   Elf32_Rela* rtab = (Elf32_Rela*) (ehdrC + shdr[shnum].sh_offset);
-   int         nent = shdr[shnum].sh_size / sizeof(Elf32_Rela);
+   Elf_Addr targ;
+   Elf_Rela* rtab = (Elf_Rela*) (ehdrC + shdr[shnum].sh_offset);
+   int         nent = shdr[shnum].sh_size / sizeof(Elf_Rela);
    int target_shndx = shdr[shnum].sh_info;
    int symtab_shndx = shdr[shnum].sh_link;
-   stab  = (Elf32_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
-   targ  = (Elf32_Word*)(ehdrC + shdr[ target_shndx ].sh_offset);
+
+   stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
+   targ  = (Elf_Addr) (ehdrC + shdr[ target_shndx ].sh_offset);
    IF_DEBUG(linker,belch( "relocations for section %d using symtab %d",
                           target_shndx, symtab_shndx ));
-   for (j = 0; j < nent; j++) {
-      Elf32_Addr  offset = rtab[j].r_offset;
-      Elf32_Word  info   = rtab[j].r_info;
-      Elf32_Sword addend = rtab[j].r_addend;
 
-      Elf32_Addr  P  = ((Elf32_Addr)targ) + offset;
-      Elf32_Addr  A  = addend;
-      Elf32_Addr  S;
-#     if defined(sparc_TARGET_ARCH)
+   for (j = 0; j < nent; j++) {
+#if defined(DEBUG) || defined(sparc_TARGET_ARCH) || defined(ia64_TARGET_ARCH)
       /* This #ifdef only serves to avoid unused-var warnings. */
-      Elf32_Word* pP = (Elf32_Word*)P;
-      Elf32_Word  w1, w2;
+      Elf_Addr  offset = rtab[j].r_offset;
+      Elf_Addr  P      = targ + offset;
+#endif
+      Elf_Addr  info   = rtab[j].r_info;
+      Elf_Addr  A      = rtab[j].r_addend;
+      Elf_Addr  S;
+      Elf_Addr  value;
+#     if defined(sparc_TARGET_ARCH)
+      Elf_Word* pP = (Elf_Word*)P;
+      Elf_Word  w1, w2;
+#     elif defined(ia64_TARGET_ARCH)
+      Elf64_Xword *pP = (Elf64_Xword *)P;
+      Elf_Addr addr;
 #     endif
 
-      IF_DEBUG(linker,belch( "Rel entry %3d is raw(%6p %6p %6p)   ", 
-                             j, (void*)offset, (void*)info, 
-                                (void*)addend ));
+      IF_DEBUG(linker,belch( "Rel entry %3d is raw(%6p %6p %6p)   ",
+                             j, (void*)offset, (void*)info,
+                                (void*)A ));
       if (!info) {
          IF_DEBUG(linker,belch( " ZERO" ));
          S = 0;
       } else {
-         /* First see if it is a nameless local symbol. */
-         if (stab[ ELF32_R_SYM(info)].st_name == 0) {
-            symbol = "(noname)";
-            S = (Elf32_Addr)
-                (ehdrC + shdr[stab[ELF32_R_SYM(info)].st_shndx ].sh_offset
-                       + stab[ELF32_R_SYM(info)].st_value);
-         } else {
-            /* No?  Should be in a symbol table then; first try the
-               local one. */
-            symbol = strtab+stab[ ELF32_R_SYM(info)].st_name;
-            (void*)S = lookupLocalSymbol( oc, symbol );
-            if ((void*)S == NULL)
-               (void*)S = lookupSymbol( symbol );
-         }
+         Elf_Sym sym = stab[ELF_R_SYM(info)];
+        /* First see if it is a local symbol. */
+         if (ELF_ST_BIND(sym.st_info) == STB_LOCAL) {
+            /* Yes, so we can get the address directly from the ELF symbol
+               table. */
+            symbol = sym.st_name==0 ? "(noname)" : strtab+sym.st_name;
+            S = (Elf_Addr)
+                (ehdrC + shdr[ sym.st_shndx ].sh_offset
+                       + stab[ELF_R_SYM(info)].st_value);
+#ifdef ELF_FUNCTION_DESC
+           /* Make a function descriptor for this function */
+            if (S && ELF_ST_TYPE(sym.st_info) == STT_FUNC) {
+               S = allocateFunctionDesc(S + A);
+                      A = 0;
+            }
+#endif
+        } else {
+            /* No, so look up the name in our global table. */
+            symbol = strtab + sym.st_name;
+            (void*)S = lookupSymbol( symbol );
+
+#ifdef ELF_FUNCTION_DESC
+           /* If a function, already a function descriptor - we would
+              have to copy it to add an offset. */
+            if (S && (ELF_ST_TYPE(sym.st_info) == STT_FUNC) && (A != 0))
+               belch("%s: function %s with addend %p", oc->fileName, symbol, (void *)A);
+#endif
+        }
          if (!S) {
-          barf("do_Elf32_Rela_relocations: %s: unknown symbol `%s'", 
-                   oc->fileName, symbol);
-          /* 
-          S = 0x11223344;
-          fprintf ( stderr, "S %p A %p S+A %p S+A-P %p\n",S,A,S+A,S+A-P);
-          */
+          belch("%s: unknown symbol `%s'", oc->fileName, symbol);
+          return 0;
          }
          IF_DEBUG(linker,belch( "`%s' resolves to %p", symbol, (void*)S ));
       }
+
       IF_DEBUG(linker,fprintf ( stderr, "Reloc: P = %p   S = %p   A = %p\n",
-                                        (void*)P, (void*)S, (void*)A )); 
-      switch (ELF32_R_TYPE(info)) {
+                                        (void*)P, (void*)S, (void*)A ));
+      /* checkProddableBlock ( oc, (void*)P ); */
+
+      value = S + A;
+
+      switch (ELF_R_TYPE(info)) {
 #        if defined(sparc_TARGET_ARCH)
-         case R_SPARC_WDISP30: 
+         case R_SPARC_WDISP30:
             w1 = *pP & 0xC0000000;
-            w2 = (Elf32_Word)((S + A - P) >> 2);
+            w2 = (Elf_Word)((value - P) >> 2);
             ASSERT((w2 & 0xC0000000) == 0);
             w1 |= w2;
             *pP = w1;
             break;
          case R_SPARC_HI22:
             w1 = *pP & 0xFFC00000;
-            w2 = (Elf32_Word)((S + A) >> 10);
+            w2 = (Elf_Word)(value >> 10);
             ASSERT((w2 & 0xFFC00000) == 0);
             w1 |= w2;
             *pP = w1;
             break;
          case R_SPARC_LO10:
             w1 = *pP & ~0x3FF;
-            w2 = (Elf32_Word)((S + A) & 0x3FF);
+            w2 = (Elf_Word)(value & 0x3FF);
             ASSERT((w2 & ~0x3FF) == 0);
             w1 |= w2;
             *pP = w1;
             break;
+         /* According to the Sun documentation:
+            R_SPARC_UA32
+            This relocation type resembles R_SPARC_32, except it refers to an
+            unaligned word. That is, the word to be relocated must be treated
+            as four separate bytes with arbitrary alignment, not as a word
+            aligned according to the architecture requirements.
+
+            (JRS: which means that freeloading on the R_SPARC_32 case
+            is probably wrong, but hey ...)
+         */
+         case R_SPARC_UA32:
          case R_SPARC_32:
-            w2 = (Elf32_Word)(S + A);
+            w2 = (Elf_Word)value;
             *pP = w2;
             break;
+#        elif defined(ia64_TARGET_ARCH)
+        case R_IA64_DIR64LSB:
+        case R_IA64_FPTR64LSB:
+           *pP = value;
+           break;
+        case R_IA64_PCREL64LSB:
+           *pP = value - P;
+           break;
+        case R_IA64_SEGREL64LSB:
+           addr = findElfSegment(ehdrC, value);
+           *pP = value - addr;
+           break;
+        case R_IA64_GPREL22:
+           ia64_reloc_gprel22(P, value);
+           break;
+        case R_IA64_LTOFF22:
+        case R_IA64_LTOFF22X:
+        case R_IA64_LTOFF_FPTR22:
+           addr = allocateGOTEntry(value);
+           ia64_reloc_gprel22(P, addr);
+           break;
+        case R_IA64_PCREL21B:
+           ia64_reloc_pcrel21(P, S, oc);
+           break;
+        case R_IA64_LDXMOV:
+           /* This goes with R_IA64_LTOFF22X and points to the load to
+            * convert into a move.  We don't implement relaxation. */
+           break;
 #        endif
-         default: 
-            fprintf(stderr, "unhandled ELF relocation(RelA) type %d\n",
-                            ELF32_R_TYPE(info));
-            barf("do_Elf32_Rela_relocations: unhandled ELF relocation type");
+         default:
+            belch("%s: unhandled ELF relocation(RelA) type %d\n",
+                 oc->fileName, ELF_R_TYPE(info));
             return 0;
       }
 
@@ -1853,39 +2857,47 @@ static int do_Elf32_Rela_relocations ( ObjectCode* oc, char* ehdrC,
    return 1;
 }
 
-
 static int
 ocResolve_ELF ( ObjectCode* oc )
 {
    char *strtab;
    int   shnum, ok;
-   Elf32_Sym*  stab = NULL;
-   char*       ehdrC = (char*)(oc->image);
-   Elf32_Ehdr* ehdr = (Elf32_Ehdr*) ehdrC;
-   Elf32_Shdr* shdr = (Elf32_Shdr*) (ehdrC + ehdr->e_shoff);
+   Elf_Sym*  stab  = NULL;
+   char*     ehdrC = (char*)(oc->image);
+   Elf_Ehdr* ehdr  = (Elf_Ehdr*) ehdrC;
+   Elf_Shdr* shdr  = (Elf_Shdr*) (ehdrC + ehdr->e_shoff);
+   char* sh_strtab = ehdrC + shdr[ehdr->e_shstrndx].sh_offset;
 
    /* first find "the" symbol table */
-   stab = (Elf32_Sym*) findElfSection ( ehdrC, SHT_SYMTAB );
+   stab = (Elf_Sym*) findElfSection ( ehdrC, SHT_SYMTAB );
 
    /* also go find the string table */
    strtab = findElfSection ( ehdrC, SHT_STRTAB );
 
    if (stab == NULL || strtab == NULL) {
-      belch("ocResolve_ELF: can't find string or symbol table");
-      return 0; 
+      belch("%s: can't find string or symbol table", oc->fileName);
+      return 0;
    }
 
    /* Process the relocation sections. */
    for (shnum = 0; shnum < ehdr->e_shnum; shnum++) {
+
+      /* Skip sections called ".rel.stab".  These appear to contain
+         relocation entries that, when done, make the stabs debugging
+         info point at the right places.  We ain't interested in all
+         dat jazz, mun. */
+      if (0 == memcmp(".rel.stab", sh_strtab + shdr[shnum].sh_name, 9))
+         continue;
+
       if (shdr[shnum].sh_type == SHT_REL ) {
-         ok = do_Elf32_Rel_relocations ( oc, ehdrC, shdr, 
-                                         shnum, stab, strtab );
+         ok = do_Elf_Rel_relocations ( oc, ehdrC, shdr,
+                                       shnum, stab, strtab );
          if (!ok) return ok;
       }
       else
       if (shdr[shnum].sh_type == SHT_RELA) {
-         ok = do_Elf32_Rela_relocations ( oc, ehdrC, shdr, 
-                                          shnum, stab, strtab );
+         ok = do_Elf_Rela_relocations ( oc, ehdrC, shdr,
+                                        shnum, stab, strtab );
          if (!ok) return ok;
       }
    }
@@ -1897,5 +2909,682 @@ ocResolve_ELF ( ObjectCode* oc )
    return 1;
 }
 
+/*
+ * IA64 specifics
+ * Instructions are 41 bits long, packed into 128 bit bundles with a 5-bit template
+ * at the front.  The following utility functions pack and unpack instructions, and
+ * take care of the most common relocations.
+ */
+
+#ifdef ia64_TARGET_ARCH
+
+static Elf64_Xword
+ia64_extract_instruction(Elf64_Xword *target)
+{
+   Elf64_Xword w1, w2;
+   int slot = (Elf_Addr)target & 3;
+   (Elf_Addr)target &= ~3;
+
+   w1 = *target;
+   w2 = *(target+1);
+
+   switch (slot)
+   {
+      case 0:
+         return ((w1 >> 5) & 0x1ffffffffff);
+      case 1:
+         return (w1 >> 46) | ((w2 & 0x7fffff) << 18);
+      case 2:
+         return (w2 >> 23);
+      default:
+         barf("ia64_extract_instruction: invalid slot %p", target);
+   }
+}
+
+static void
+ia64_deposit_instruction(Elf64_Xword *target, Elf64_Xword value)
+{
+   int slot = (Elf_Addr)target & 3;
+   (Elf_Addr)target &= ~3;
+
+   switch (slot)
+   {
+      case 0:
+         *target |= value << 5;
+         break;
+      case 1:
+         *target |= value << 46;
+         *(target+1) |= value >> 18;
+         break;
+      case 2:
+         *(target+1) |= value << 23;
+         break;
+   }
+}
+
+static void
+ia64_reloc_gprel22(Elf_Addr target, Elf_Addr value)
+{
+   Elf64_Xword instruction;
+   Elf64_Sxword rel_value;
+
+   rel_value = value - gp_val;
+   if ((rel_value > 0x1fffff) || (rel_value < -0x1fffff))
+      barf("GP-relative data out of range (address = 0x%lx, gp = 0x%lx)", value, gp_val);
+
+   instruction = ia64_extract_instruction((Elf64_Xword *)target);
+   instruction |= (((rel_value >> 0) & 0x07f) << 13)           /* imm7b */
+                   | (((rel_value >> 7) & 0x1ff) << 27)        /* imm9d */
+                   | (((rel_value >> 16) & 0x01f) << 22)       /* imm5c */
+                   | ((Elf64_Xword)(rel_value < 0) << 36);     /* s */
+   ia64_deposit_instruction((Elf64_Xword *)target, instruction);
+}
+
+static void
+ia64_reloc_pcrel21(Elf_Addr target, Elf_Addr value, ObjectCode *oc)
+{
+   Elf64_Xword instruction;
+   Elf64_Sxword rel_value;
+   Elf_Addr entry;
+
+   entry = allocatePLTEntry(value, oc);
+
+   rel_value = (entry >> 4) - (target >> 4);
+   if ((rel_value > 0xfffff) || (rel_value < -0xfffff))
+      barf("PLT entry too far away (entry = 0x%lx, target = 0x%lx)", entry, target);
+
+   instruction = ia64_extract_instruction((Elf64_Xword *)target);
+   instruction |= ((rel_value & 0xfffff) << 13)                /* imm20b */
+                   | ((Elf64_Xword)(rel_value < 0) << 36);     /* s */
+   ia64_deposit_instruction((Elf64_Xword *)target, instruction);
+}
+
+#endif /* ia64 */
 
 #endif /* ELF */
+
+/* --------------------------------------------------------------------------
+ * Mach-O specifics
+ * ------------------------------------------------------------------------*/
+
+#if defined(OBJFORMAT_MACHO)
+
+/*
+  Support for MachO linking on Darwin/MacOS X on PowerPC chips
+  by Wolfgang Thaller (wolfgang.thaller@gmx.net)
+  
+  I hereby formally apologize for the hackish nature of this code.
+  Things that need to be done:
+  *) implement ocVerifyImage_MachO
+  *) add still more sanity checks.
+*/
+
+
+/*
+  ocAllocateJumpIslands_MachO
+  
+  Allocate additional space at the end of the object file image to make room
+  for jump islands.
+  
+  PowerPC relative branch instructions have a 24 bit displacement field.
+  As PPC code is always 4-byte-aligned, this yields a +-32MB range.
+  If a particular imported symbol is outside this range, we have to redirect
+  the jump to a short piece of new code that just loads the 32bit absolute
+  address and jumps there.
+  This function just allocates space for one 16 byte jump island for every
+  undefined symbol in the object file. The code for the islands is filled in by
+  makeJumpIsland below.
+*/
+
+static const int islandSize = 16;
+
+static int ocAllocateJumpIslands_MachO(ObjectCode* oc)
+{
+    char *image = (char*) oc->image;
+    struct mach_header *header = (struct mach_header*) image;
+    struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
+    unsigned i;
+
+    for(i=0;i<header->ncmds;i++)
+    {
+       if(lc->cmd == LC_DYSYMTAB)
+        {
+           struct dysymtab_command *dsymLC = (struct dysymtab_command*) lc;
+            unsigned long nundefsym = dsymLC->nundefsym;
+            oc->island_start_symbol = dsymLC->iundefsym;
+            oc->n_islands = nundefsym;
+            
+            if(nundefsym > 0)
+            {
+#ifdef USE_MMAP
+                #error ocAllocateJumpIslands_MachO doesnt want USE_MMAP to be defined
+#else
+                oc->image = stgReallocBytes(
+                    image, oc->fileSize + islandSize * nundefsym,
+                    "ocAllocateJumpIslands_MachO");
+#endif                    
+                oc->jump_islands = oc->image + oc->fileSize;
+                memset(oc->jump_islands, 0, islandSize * nundefsym);
+            }
+            
+            break;  // there can be only one LC_DSYMTAB
+        }
+       lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
+    }
+    return 1;
+}
+
+static int ocVerifyImage_MachO(ObjectCode* oc)
+{
+    // FIXME: do some verifying here
+    return 1;
+}
+
+static int resolveImports(
+    ObjectCode* oc,
+    char *image,
+    struct symtab_command *symLC,
+    struct section *sect,    // ptr to lazy or non-lazy symbol pointer section
+    unsigned long *indirectSyms,
+    struct nlist *nlist)
+{
+    unsigned i;
+    
+    for(i=0;i*4<sect->size;i++)
+    {
+       // according to otool, reserved1 contains the first index into the indirect symbol table
+       struct nlist *symbol = &nlist[indirectSyms[sect->reserved1+i]];
+       char *nm = image + symLC->stroff + symbol->n_un.n_strx;
+       void *addr = NULL;
+       
+       if((symbol->n_type & N_TYPE) == N_UNDF
+           && (symbol->n_type & N_EXT) && (symbol->n_value != 0))
+           addr = (void*) (symbol->n_value);
+       else if((addr = lookupLocalSymbol(oc,nm)) != NULL)
+           ;
+       else
+           addr = lookupSymbol(nm);
+       if(!addr)
+       {
+           belch("\n%s: unknown symbol `%s'", oc->fileName, nm);
+           return 0;
+       }
+       ASSERT(addr);
+       checkProddableBlock(oc,((void**)(image + sect->offset)) + i);
+       ((void**)(image + sect->offset))[i] = addr;
+    }
+    
+    return 1;
+}
+
+static void* makeJumpIsland(
+    ObjectCode* oc,
+    unsigned long symbolNumber,
+    void* target)
+{
+    if(symbolNumber < oc->island_start_symbol ||
+        symbolNumber - oc->island_start_symbol > oc->n_islands)
+        return NULL;
+    symbolNumber -= oc->island_start_symbol;
+    
+    void *island = (void*) ((char*)oc->jump_islands + islandSize * symbolNumber);
+    unsigned long *p = (unsigned long*) island;
+    
+        // lis r12, hi16(target)
+    *p++ = 0x3d800000 | ( ((unsigned long) target) >> 16 );
+        // ori r12, r12, lo16(target)
+    *p++ = 0x618c0000 | ( ((unsigned long) target) & 0xFFFF ); 
+        // mtctr r12
+    *p++ = 0x7d8903a6;
+        // bctr
+    *p++ = 0x4e800420;
+    
+    return (void*) island;
+}
+
+static char* relocateAddress(
+    ObjectCode* oc,
+    int nSections,
+    struct section* sections,
+    unsigned long address)
+{  
+    int i;
+    for(i = 0; i < nSections; i++)
+    {
+        if(sections[i].addr <= address
+            && address < sections[i].addr + sections[i].size)
+        {
+            return oc->image + sections[i].offset + address - sections[i].addr;
+        }
+    }
+    barf("Invalid Mach-O file:"
+         "Address out of bounds while relocating object file");
+    return NULL;
+}
+
+static int relocateSection(
+    ObjectCode* oc,
+    char *image, 
+    struct symtab_command *symLC, struct nlist *nlist,
+    int nSections, struct section* sections, struct section *sect)
+{
+    struct relocation_info *relocs;
+    int i,n;
+    
+    if(!strcmp(sect->sectname,"__la_symbol_ptr"))
+       return 1;
+    else if(!strcmp(sect->sectname,"__nl_symbol_ptr"))
+       return 1;
+
+    n = sect->nreloc;
+    relocs = (struct relocation_info*) (image + sect->reloff);
+    
+    for(i=0;i<n;i++)
+    {
+       if(relocs[i].r_address & R_SCATTERED)
+       {
+           struct scattered_relocation_info *scat =
+               (struct scattered_relocation_info*) &relocs[i];
+           
+           if(!scat->r_pcrel)
+           {
+               if(scat->r_length == 2)
+               {
+                   unsigned long word = 0;
+                   unsigned long* wordPtr = (unsigned long*) (image + sect->offset + scat->r_address);
+                   checkProddableBlock(oc,wordPtr);
+                   
+                   // Step 1: Figure out what the relocated value should be
+                   if(scat->r_type == GENERIC_RELOC_VANILLA)
+                   {
+                       word = scat->r_value + sect->offset + ((long) image);
+                   }
+                   else if(scat->r_type == PPC_RELOC_SECTDIFF
+                       || scat->r_type == PPC_RELOC_LO16_SECTDIFF
+                       || scat->r_type == PPC_RELOC_HI16_SECTDIFF
+                       || scat->r_type == PPC_RELOC_HA16_SECTDIFF)
+                   {
+                       struct scattered_relocation_info *pair =
+                               (struct scattered_relocation_info*) &relocs[i+1];
+                               
+                       if(!pair->r_scattered || pair->r_type != PPC_RELOC_PAIR)
+                           barf("Invalid Mach-O file: "
+                                "PPC_RELOC_*_SECTDIFF not followed by PPC_RELOC_PAIR");
+                       
+                       word = (unsigned long)
+                              (relocateAddress(oc, nSections, sections, scat->r_value)
+                             - relocateAddress(oc, nSections, sections, pair->r_value));
+                       i++;
+                   }
+                   else
+                       continue;  // ignore the others
+
+                    if(scat->r_type == GENERIC_RELOC_VANILLA
+                        || scat->r_type == PPC_RELOC_SECTDIFF)
+                    {
+                        *wordPtr = word;
+                    }
+                    else if(scat->r_type == PPC_RELOC_LO16_SECTDIFF)
+                    {
+                        ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
+                    }
+                    else if(scat->r_type == PPC_RELOC_HI16_SECTDIFF)
+                    {
+                        ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
+                    }
+                    else if(scat->r_type == PPC_RELOC_HA16_SECTDIFF)
+                    {
+                        ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
+                            + ((word & (1<<15)) ? 1 : 0);
+                    }
+               }
+           }
+           
+           continue; // FIXME: I hope it's OK to ignore all the others.
+       }
+       else
+       {
+           struct relocation_info *reloc = &relocs[i];
+           if(reloc->r_pcrel && !reloc->r_extern)
+               continue;
+               
+           if(reloc->r_length == 2)
+           {
+               unsigned long word = 0;
+                unsigned long jumpIsland = 0;
+                long offsetToJumpIsland;
+                
+               unsigned long* wordPtr = (unsigned long*) (image + sect->offset + reloc->r_address);
+               checkProddableBlock(oc,wordPtr);
+               
+               if(reloc->r_type == GENERIC_RELOC_VANILLA)
+               {
+                   word = *wordPtr;
+               }
+               else if(reloc->r_type == PPC_RELOC_LO16)
+               {
+                   word = ((unsigned short*) wordPtr)[1];
+                   word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF) << 16;
+               }
+               else if(reloc->r_type == PPC_RELOC_HI16)
+               {
+                   word = ((unsigned short*) wordPtr)[1] << 16;
+                   word |= ((unsigned long) relocs[i+1].r_address & 0xFFFF);
+               }
+               else if(reloc->r_type == PPC_RELOC_HA16)
+               {
+                   word = ((unsigned short*) wordPtr)[1] << 16;
+                   word += ((short)relocs[i+1].r_address & (short)0xFFFF);
+               }
+               else if(reloc->r_type == PPC_RELOC_BR24)
+               {
+                   word = *wordPtr;
+                   word = (word & 0x03FFFFFC) | (word & 0x02000000) ? 0xFC000000 : 0;
+               }
+
+
+               if(!reloc->r_extern)
+               {
+                   long delta = 
+                       sections[reloc->r_symbolnum-1].offset
+                       - sections[reloc->r_symbolnum-1].addr
+                       + ((long) image);
+                   
+                   word += delta;
+               }
+               else
+               {
+                   struct nlist *symbol = &nlist[reloc->r_symbolnum];
+                   char *nm = image + symLC->stroff + symbol->n_un.n_strx;
+                   word = (unsigned long) (lookupSymbol(nm));
+                   if(!word)
+                   {
+                       belch("\nunknown symbol `%s'", nm);
+                       return 0;
+                   }
+                   
+                   if(reloc->r_pcrel)
+                    {
+                        jumpIsland = (long) makeJumpIsland(oc,reloc->r_symbolnum,(void*)word);
+                       word -= ((long)image) + sect->offset + reloc->r_address;
+                        if(jumpIsland != 0)
+                        {
+                            offsetToJumpIsland = jumpIsland
+                                - (((long)image) + sect->offset + reloc->r_address);
+                        }
+                    }
+               }
+               
+               if(reloc->r_type == GENERIC_RELOC_VANILLA)
+               {
+                   *wordPtr = word;
+                   continue;
+               }
+               else if(reloc->r_type == PPC_RELOC_LO16)
+               {
+                   ((unsigned short*) wordPtr)[1] = word & 0xFFFF;
+                   i++; continue;
+               }
+               else if(reloc->r_type == PPC_RELOC_HI16)
+               {
+                   ((unsigned short*) wordPtr)[1] = (word >> 16) & 0xFFFF;
+                   i++; continue;
+               }
+               else if(reloc->r_type == PPC_RELOC_HA16)
+               {
+                   ((unsigned short*) wordPtr)[1] = ((word >> 16) & 0xFFFF)
+                       + ((word & (1<<15)) ? 1 : 0);
+                   i++; continue;
+               }
+               else if(reloc->r_type == PPC_RELOC_BR24)
+               {
+                    if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
+                    {
+                        // The branch offset is too large.
+                        // Therefore, we try to use a jump island.
+                        if(jumpIsland == 0)
+                            barf("unconditional relative branch out of range: "
+                                 "no jump island available");
+                            
+                        word = offsetToJumpIsland;
+                        if((long)word > (long)0x01FFFFFF || (long)word < (long)0xFFE00000)
+                            barf("unconditional relative branch out of range: "
+                                 "jump island out of range");
+                    }
+                   *wordPtr = (*wordPtr & 0xFC000003) | (word & 0x03FFFFFC);
+                   continue;
+               }
+           }
+           barf("\nunknown relocation %d",reloc->r_type);
+           return 0;
+       }
+    }
+    return 1;
+}
+
+static int ocGetNames_MachO(ObjectCode* oc)
+{
+    char *image = (char*) oc->image;
+    struct mach_header *header = (struct mach_header*) image;
+    struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
+    unsigned i,curSymbol;
+    struct segment_command *segLC = NULL;
+    struct section *sections;
+    struct symtab_command *symLC = NULL;
+    struct dysymtab_command *dsymLC = NULL;
+    struct nlist *nlist;
+    unsigned long commonSize = 0;
+    char    *commonStorage = NULL;
+    unsigned long commonCounter;
+
+    for(i=0;i<header->ncmds;i++)
+    {
+       if(lc->cmd == LC_SEGMENT)
+           segLC = (struct segment_command*) lc;
+       else if(lc->cmd == LC_SYMTAB)
+           symLC = (struct symtab_command*) lc;
+       else if(lc->cmd == LC_DYSYMTAB)
+           dsymLC = (struct dysymtab_command*) lc;
+       lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
+    }
+
+    sections = (struct section*) (segLC+1); 
+    nlist = (struct nlist*) (image + symLC->symoff);
+
+    for(i=0;i<segLC->nsects;i++)
+    {
+        if(sections[i].size == 0)
+            continue;
+        
+        if((sections[i].flags & SECTION_TYPE) == S_ZEROFILL)
+        {
+            char * zeroFillArea = stgCallocBytes(1,sections[i].size,
+                                      "ocGetNames_MachO(common symbols)");
+            sections[i].offset = zeroFillArea - image;
+        }
+    
+       if(!strcmp(sections[i].sectname,"__text"))
+           addSection(oc, SECTIONKIND_CODE_OR_RODATA, 
+               (void*) (image + sections[i].offset),
+               (void*) (image + sections[i].offset + sections[i].size));
+       else if(!strcmp(sections[i].sectname,"__const"))
+           addSection(oc, SECTIONKIND_RWDATA, 
+               (void*) (image + sections[i].offset),
+               (void*) (image + sections[i].offset + sections[i].size));
+       else if(!strcmp(sections[i].sectname,"__data"))
+           addSection(oc, SECTIONKIND_RWDATA, 
+               (void*) (image + sections[i].offset),
+               (void*) (image + sections[i].offset + sections[i].size));
+       else if(!strcmp(sections[i].sectname,"__bss")
+               || !strcmp(sections[i].sectname,"__common"))
+           addSection(oc, SECTIONKIND_RWDATA, 
+               (void*) (image + sections[i].offset),
+               (void*) (image + sections[i].offset + sections[i].size));
+
+        addProddableBlock(oc, (void*) (image + sections[i].offset),
+                                        sections[i].size);
+    }
+
+       // count external symbols defined here
+    oc->n_symbols = 0;
+    for(i=dsymLC->iextdefsym;i<dsymLC->iextdefsym+dsymLC->nextdefsym;i++)
+    {
+       if((nlist[i].n_type & N_TYPE) == N_SECT)
+           oc->n_symbols++;
+    }
+    for(i=0;i<symLC->nsyms;i++)
+    {
+       if((nlist[i].n_type & N_TYPE) == N_UNDF
+               && (nlist[i].n_type & N_EXT) && (nlist[i].n_value != 0))
+       {
+           commonSize += nlist[i].n_value;
+           oc->n_symbols++;
+       }
+    }
+    oc->symbols = stgMallocBytes(oc->n_symbols * sizeof(char*),
+                                  "ocGetNames_MachO(oc->symbols)");
+    
+       // insert symbols into hash table
+    for(i=dsymLC->iextdefsym,curSymbol=0;i<dsymLC->iextdefsym+dsymLC->nextdefsym;i++)
+    {
+       if((nlist[i].n_type & N_TYPE) == N_SECT)
+       {
+           char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
+           ghciInsertStrHashTable(oc->fileName, symhash, nm, image + 
+               sections[nlist[i].n_sect-1].offset
+               - sections[nlist[i].n_sect-1].addr
+               + nlist[i].n_value);
+           oc->symbols[curSymbol++] = nm;
+       }
+    }
+    
+       // insert local symbols into lochash
+    for(i=dsymLC->ilocalsym;i<dsymLC->ilocalsym+dsymLC->nlocalsym;i++)
+    {
+       if((nlist[i].n_type & N_TYPE) == N_SECT)
+       {
+           char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
+           ghciInsertStrHashTable(oc->fileName, oc->lochash, nm, image + 
+               sections[nlist[i].n_sect-1].offset
+               - sections[nlist[i].n_sect-1].addr
+               + nlist[i].n_value);
+       }
+    }
+
+    
+    commonStorage = stgCallocBytes(1,commonSize,"ocGetNames_MachO(common symbols)");
+    commonCounter = (unsigned long)commonStorage;
+    for(i=0;i<symLC->nsyms;i++)
+    {
+       if((nlist[i].n_type & N_TYPE) == N_UNDF
+               && (nlist[i].n_type & N_EXT) && (nlist[i].n_value != 0))
+       {
+           char *nm = image + symLC->stroff + nlist[i].n_un.n_strx;
+           unsigned long sz = nlist[i].n_value;
+           
+           nlist[i].n_value = commonCounter;
+           
+           ghciInsertStrHashTable(oc->fileName, symhash, nm, (void*)commonCounter);
+           oc->symbols[curSymbol++] = nm;
+           
+           commonCounter += sz;
+       }
+    }
+    return 1;
+}
+
+static int ocResolve_MachO(ObjectCode* oc)
+{
+    char *image = (char*) oc->image;
+    struct mach_header *header = (struct mach_header*) image;
+    struct load_command *lc = (struct load_command*) (image + sizeof(struct mach_header));
+    unsigned i;
+    struct segment_command *segLC = NULL;
+    struct section *sections, *la_ptrs = NULL, *nl_ptrs = NULL;
+    struct symtab_command *symLC = NULL;
+    struct dysymtab_command *dsymLC = NULL;
+    struct nlist *nlist;
+    unsigned long *indirectSyms;
+
+    for(i=0;i<header->ncmds;i++)
+    {
+       if(lc->cmd == LC_SEGMENT)
+           segLC = (struct segment_command*) lc;
+       else if(lc->cmd == LC_SYMTAB)
+           symLC = (struct symtab_command*) lc;
+       else if(lc->cmd == LC_DYSYMTAB)
+           dsymLC = (struct dysymtab_command*) lc;
+       lc = (struct load_command *) ( ((char*)lc) + lc->cmdsize );
+    }
+    
+    sections = (struct section*) (segLC+1); 
+    nlist = (struct nlist*) (image + symLC->symoff);
+
+    for(i=0;i<segLC->nsects;i++)
+    {
+       if(!strcmp(sections[i].sectname,"__la_symbol_ptr"))
+           la_ptrs = &sections[i];
+       else if(!strcmp(sections[i].sectname,"__nl_symbol_ptr"))
+           nl_ptrs = &sections[i];
+    }
+    
+    indirectSyms = (unsigned long*) (image + dsymLC->indirectsymoff);
+
+    if(la_ptrs)
+       if(!resolveImports(oc,image,symLC,la_ptrs,indirectSyms,nlist))
+           return 0;
+    if(nl_ptrs)
+       if(!resolveImports(oc,image,symLC,nl_ptrs,indirectSyms,nlist))
+           return 0;
+    
+    for(i=0;i<segLC->nsects;i++)
+    {
+       if(!relocateSection(oc,image,symLC,nlist,segLC->nsects,sections,&sections[i]))
+           return 0;
+    }
+
+    /* Free the local symbol table; we won't need it again. */
+    freeHashTable(oc->lochash, NULL);
+    oc->lochash = NULL;
+    
+    /*
+        Flush the data & instruction caches.
+        Because the PPC has split data/instruction caches, we have to
+        do that whenever we modify code at runtime.
+    */
+    {
+        int n = (oc->fileSize + islandSize * oc->n_islands) / 4;
+        unsigned long *p = (unsigned long*)oc->image;
+        while(n--)
+        {
+            __asm__ volatile ("dcbf 0,%0\n\tsync\n\ticbi 0,%0"
+                                : : "r" (p));
+            p++;
+        }
+        __asm__ volatile ("sync\n\tisync");
+    }
+    return 1;
+}
+
+/*
+ * The Mach-O object format uses leading underscores. But not everywhere.
+ * There is a small number of runtime support functions defined in
+ * libcc_dynamic.a whose name does not have a leading underscore.
+ * As a consequence, we can't get their address from C code.
+ * We have to use inline assembler just to take the address of a function.
+ * Yuck.
+ */
+
+static void machoInitSymbolsWithoutUnderscore()
+{
+    void *p;
+
+#undef Sym    
+#define Sym(x)                                         \
+    __asm__ ("lis %0,hi16(" #x ")\n\tori %0,%0,lo16(" #x ")" : "=r" (p));      \
+    ghciInsertStrHashTable("(GHCi built-in symbols)", symhash, #x, p);
+    
+    RTS_MACHO_NOUNDERLINE_SYMBOLS
+
+}
+#endif