Linker.c 138 KB
Newer Older
1 2
/* -----------------------------------------------------------------------------
 *
3
 * (c) The GHC Team, 2000-2004
4 5 6 7 8
 *
 * RTS Object Linker
 *
 * ---------------------------------------------------------------------------*/

sof's avatar
sof committed
9
#if 0
10
#include "PosixSource.h"
sof's avatar
sof committed
11
#endif
12

13 14 15
/* Linux needs _GNU_SOURCE to get RTLD_DEFAULT from <dlfcn.h> and 
   MREMAP_MAYMOVE from <sys/mman.h>.
 */
16 17 18 19
#ifdef __linux__
#define _GNU_SOURCE
#endif

20 21 22 23 24
#include "Rts.h"
#include "RtsFlags.h"
#include "HsFFI.h"
#include "Hash.h"
#include "Linker.h"
25
#include "LinkerInternals.h"
26
#include "RtsUtils.h"
27
#include "Schedule.h"
28
#include "Storage.h"
29
#include "Sparks.h"
30

31
#ifdef HAVE_SYS_TYPES_H
32
#include <sys/types.h>
33 34
#endif

35 36 37
#include <stdlib.h>
#include <string.h>

38
#ifdef HAVE_SYS_STAT_H
39
#include <sys/stat.h>
40
#endif
41

42
#if defined(HAVE_DLFCN_H)
43
#include <dlfcn.h>
44
#endif
45

46
#if defined(cygwin32_HOST_OS)
sof's avatar
sof committed
47 48 49 50 51 52 53 54 55 56 57 58 59 60 61
#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

62
#if defined(ia64_HOST_ARCH) || defined(openbsd_HOST_OS) || defined(linux_HOST_OS) || defined(freebsd_HOST_OS)
63 64 65
#define USE_MMAP
#include <fcntl.h>
#include <sys/mman.h>
dons's avatar
dons committed
66

67
#if defined(openbsd_HOST_OS) || defined(linux_HOST_OS) || defined(freebsd_HOST_OS)
dons's avatar
dons committed
68 69 70 71 72
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#endif

73 74
#endif

75
#if defined(linux_HOST_OS) || defined(solaris2_HOST_OS) || defined(freebsd_HOST_OS) || defined(netbsd_HOST_OS) || defined(openbsd_HOST_OS)
76
#  define OBJFORMAT_ELF
77
#elif defined(cygwin32_HOST_OS) || defined (mingw32_HOST_OS)
78
#  define OBJFORMAT_PEi386
79
#  include <windows.h>
sof's avatar
sof committed
80
#  include <math.h>
81
#elif defined(darwin_HOST_OS)
82 83 84 85
#  define OBJFORMAT_MACHO
#  include <mach-o/loader.h>
#  include <mach-o/nlist.h>
#  include <mach-o/reloc.h>
86
#  include <mach-o/dyld.h>
87 88 89
#if defined(powerpc_HOST_ARCH)
#  include <mach-o/ppc/reloc.h>
#endif
90 91
#endif

92
/* Hash table mapping symbol names to Symbol */
93
static /*Str*/HashTable *symhash;
94

95 96 97 98 99 100 101 102 103 104 105
typedef struct {
  void *addr;
} rootEntry;

/* Hash table mapping symbol names to StgStablePtr */
static /*Str*/HashTable *stablehash;
rootEntry *root_ptr_table = NULL;
static rootEntry *root_ptr_free = NULL;

static unsigned int RPT_size = 0;

106 107 108
/* List of currently loaded objects */
ObjectCode *objects = NULL;	/* initially empty */

109
#if defined(OBJFORMAT_ELF)
110 111 112
static int ocVerifyImage_ELF    ( ObjectCode* oc );
static int ocGetNames_ELF       ( ObjectCode* oc );
static int ocResolve_ELF        ( ObjectCode* oc );
113
#if defined(powerpc_HOST_ARCH)
114 115
static int ocAllocateJumpIslands_ELF ( ObjectCode* oc );
#endif
116
#elif defined(OBJFORMAT_PEi386)
117 118 119
static int ocVerifyImage_PEi386 ( ObjectCode* oc );
static int ocGetNames_PEi386    ( ObjectCode* oc );
static int ocResolve_PEi386     ( ObjectCode* oc );
120 121 122 123
#elif defined(OBJFORMAT_MACHO)
static int ocVerifyImage_MachO    ( ObjectCode* oc );
static int ocGetNames_MachO       ( ObjectCode* oc );
static int ocResolve_MachO        ( ObjectCode* oc );
124

125
static int machoGetMisalignment( FILE * );
126 127
#ifdef powerpc_HOST_ARCH
static int ocAllocateJumpIslands_MachO ( ObjectCode* oc );
128
static void machoInitSymbolsWithoutUnderscore( void );
129
#endif
130
#endif
131

132 133 134 135
#if defined(x86_64_HOST_ARCH)
static void*x86_64_high_symbol( char *lbl, void *addr );
#endif

136 137 138 139
/* -----------------------------------------------------------------------------
 * Built-in symbols from the RTS
 */

140 141 142 143 144 145
typedef struct _RtsSymbolVal {
    char   *lbl;
    void   *addr;
} RtsSymbolVal;


146 147 148 149 150 151 152 153
#if !defined(PAR)
#define Maybe_Stable_Names      SymX(mkWeakzh_fast)			\
      				SymX(makeStableNamezh_fast)		\
      				SymX(finalizzeWeakzh_fast)
#else
/* These are not available in GUM!!! -- HWL */
#define Maybe_Stable_Names
#endif
154

155
#if !defined (mingw32_HOST_OS)
156
#define RTS_POSIX_ONLY_SYMBOLS                  \
157
      SymX(signal_handlers)			\
158 159
      SymX(stg_sig_install)			\
      Sym(nocldstop)
sof's avatar
sof committed
160
#endif
161

162
#if defined (cygwin32_HOST_OS)
sof's avatar
sof committed
163 164 165
#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
166
 * exports; sigh.
sof's avatar
sof committed
167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243
 */
#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)                               \
244
      SymX(waitpid)
245

246
#elif !defined(mingw32_HOST_OS)
sof's avatar
sof committed
247 248
#define RTS_MINGW_ONLY_SYMBOLS /**/
#define RTS_CYGWIN_ONLY_SYMBOLS /**/
249
#else /* defined(mingw32_HOST_OS) */
sof's avatar
sof committed
250 251
#define RTS_POSIX_ONLY_SYMBOLS  /**/
#define RTS_CYGWIN_ONLY_SYMBOLS /**/
252

253 254 255 256
/* Extra syms gen'ed by mingw-2's gcc-3.2: */
#if __GNUC__>=3
#define RTS_MINGW_EXTRA_SYMS                    \
      Sym(_imp____mb_cur_max)                   \
257
      Sym(_imp___pctype)
258 259 260 261
#else
#define RTS_MINGW_EXTRA_SYMS
#endif

262 263
/* These are statically linked from the mingw libraries into the ghc
   executable, so we have to employ this hack. */
264
#define RTS_MINGW_ONLY_SYMBOLS                  \
sof's avatar
sof committed
265 266
      SymX(asyncReadzh_fast)			\
      SymX(asyncWritezh_fast)			\
sof's avatar
sof committed
267
      SymX(asyncDoProczh_fast)			\
268
      SymX(memset)                              \
269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300
      SymX(inet_ntoa)                           \
      SymX(inet_addr)                           \
      SymX(htonl)                               \
      SymX(recvfrom)                            \
      SymX(listen)                              \
      SymX(bind)                                \
      SymX(shutdown)                            \
      SymX(connect)                             \
      SymX(htons)                               \
      SymX(ntohs)                               \
      SymX(getservbyname)                       \
      SymX(getservbyport)                       \
      SymX(getprotobynumber)                    \
      SymX(getprotobyname)                      \
      SymX(gethostbyname)                       \
      SymX(gethostbyaddr)                       \
      SymX(gethostname)                         \
      SymX(strcpy)                              \
      SymX(strncpy)                             \
      SymX(abort)                               \
      Sym(_alloca)                              \
      Sym(isxdigit)                             \
      Sym(isupper)                              \
      Sym(ispunct)                              \
      Sym(islower)                              \
      Sym(isspace)                              \
      Sym(isprint)                              \
      Sym(isdigit)                              \
      Sym(iscntrl)                              \
      Sym(isalpha)                              \
      Sym(isalnum)                              \
      SymX(strcmp)                              \
301 302 303
      SymX(memmove)                             \
      SymX(realloc)                             \
      SymX(malloc)                              \
304 305 306 307 308 309 310 311 312 313 314 315 316
      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)                                \
317 318 319 320 321 322 323 324 325 326 327 328 329
      SymX(powf)                                 \
      SymX(tanhf)                                \
      SymX(coshf)                                \
      SymX(sinhf)                                \
      SymX(atanf)                                \
      SymX(acosf)                                \
      SymX(asinf)                                \
      SymX(tanf)                                 \
      SymX(cosf)                                 \
      SymX(sinf)                                 \
      SymX(expf)                                 \
      SymX(logf)                                 \
      SymX(sqrtf)                                \
330
      SymX(memcpy)                              \
sof's avatar
sof committed
331 332
      SymX(rts_InstallConsoleEvent)             \
      SymX(rts_ConsoleHandlerDone)              \
333
      Sym(mktime)                               \
334
      Sym(_imp___timezone)                      \
335
      Sym(_imp___tzname)                        \
336
      Sym(_imp___iob)                           \
sof's avatar
sof committed
337
      Sym(_imp___osver)                         \
338 339 340 341
      Sym(localtime)                            \
      Sym(gmtime)                               \
      Sym(opendir)                              \
      Sym(readdir)                              \
sof's avatar
sof committed
342
      Sym(rewinddir)                            \
343
      RTS_MINGW_EXTRA_SYMS                      \
344
      Sym(closedir)
345
#endif
346

347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396
#if defined(darwin_TARGET_OS) && HAVE_PRINTF_LDBLSTUB
#define RTS_DARWIN_ONLY_SYMBOLS			\
     Sym(asprintf$LDBLStub)                     \
     Sym(err$LDBLStub)                          \
     Sym(errc$LDBLStub)                         \
     Sym(errx$LDBLStub)                         \
     Sym(fprintf$LDBLStub)                      \
     Sym(fscanf$LDBLStub)                       \
     Sym(fwprintf$LDBLStub)                     \
     Sym(fwscanf$LDBLStub)                      \
     Sym(printf$LDBLStub)                       \
     Sym(scanf$LDBLStub)                        \
     Sym(snprintf$LDBLStub)                     \
     Sym(sprintf$LDBLStub)                      \
     Sym(sscanf$LDBLStub)                       \
     Sym(strtold$LDBLStub)                      \
     Sym(swprintf$LDBLStub)                     \
     Sym(swscanf$LDBLStub)                      \
     Sym(syslog$LDBLStub)                       \
     Sym(vasprintf$LDBLStub)                    \
     Sym(verr$LDBLStub)                         \
     Sym(verrc$LDBLStub)                        \
     Sym(verrx$LDBLStub)                        \
     Sym(vfprintf$LDBLStub)                     \
     Sym(vfscanf$LDBLStub)                      \
     Sym(vfwprintf$LDBLStub)                    \
     Sym(vfwscanf$LDBLStub)                     \
     Sym(vprintf$LDBLStub)                      \
     Sym(vscanf$LDBLStub)                       \
     Sym(vsnprintf$LDBLStub)                    \
     Sym(vsprintf$LDBLStub)                     \
     Sym(vsscanf$LDBLStub)                      \
     Sym(vswprintf$LDBLStub)                    \
     Sym(vswscanf$LDBLStub)                     \
     Sym(vsyslog$LDBLStub)                      \
     Sym(vwarn$LDBLStub)                        \
     Sym(vwarnc$LDBLStub)                       \
     Sym(vwarnx$LDBLStub)                       \
     Sym(vwprintf$LDBLStub)                     \
     Sym(vwscanf$LDBLStub)                      \
     Sym(warn$LDBLStub)                         \
     Sym(warnc$LDBLStub)                        \
     Sym(warnx$LDBLStub)                        \
     Sym(wcstold$LDBLStub)                      \
     Sym(wprintf$LDBLStub)                      \
     Sym(wscanf$LDBLStub)
#else
#define RTS_DARWIN_ONLY_SYMBOLS
#endif

sof's avatar
sof committed
397 398 399 400 401
#ifndef SMP
# define MAIN_CAP_SYM SymX(MainCapability)
#else
# define MAIN_CAP_SYM
#endif
402

sof's avatar
sof committed
403 404 405 406 407 408 409
#if !defined(mingw32_HOST_OS)
#define RTS_USER_SIGNALS_SYMBOLS \
   SymX(setIOManagerPipe)
#else
#define RTS_USER_SIGNALS_SYMBOLS /* nothing */
#endif

410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431
#ifdef TABLES_NEXT_TO_CODE
#define RTS_RET_SYMBOLS /* nothing */
#else
#define RTS_RET_SYMBOLS 			\
      SymX(stg_enter_ret)			\
      SymX(stg_gc_fun_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_pppv_ret)			\
      SymX(stg_ap_pppp_ret)			\
      SymX(stg_ap_ppppp_ret)			\
      SymX(stg_ap_pppppp_ret)
#endif

432
#define RTS_SYMBOLS				\
433 434
      Maybe_Stable_Names			\
      Sym(StgReturn)				\
435 436
      SymX(stg_enter_info)			\
      SymX(stg_gc_void_info)			\
437 438
      SymX(__stg_gc_enter_1)			\
      SymX(stg_gc_noregs)			\
439
      SymX(stg_gc_unpt_r1_info)			\
440
      SymX(stg_gc_unpt_r1)			\
441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456
      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_gen)				\
      SymX(stg_gc_gen_info)			\
      SymX(stg_gc_gen_hp)			\
      SymX(stg_gc_ut)				\
      SymX(stg_gen_yield)			\
      SymX(stg_yield_noregs)			\
457
      SymX(stg_yield_to_interpreter)		\
458 459 460 461 462 463
      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)			\
sof's avatar
sof committed
464
      MAIN_CAP_SYM                              \
465 466 467 468 469 470
      SymX(MallocFailHook)			\
      SymX(OnExitHook)				\
      SymX(OutOfHeapHook)			\
      SymX(StackOverflowHook)			\
      SymX(__encodeDouble)			\
      SymX(__encodeFloat)			\
dons's avatar
dons committed
471
      SymX(addDLL)               		\
472 473 474 475 476 477 478 479 480
      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)			\
481
      SymX(atomicallyzh_fast)			\
482
      SymX(barf)				\
483 484
      SymX(debugBelch)				\
      SymX(errorBelch)				\
485 486
      SymX(blockAsyncExceptionszh_fast)		\
      SymX(catchzh_fast)			\
487 488
      SymX(catchRetryzh_fast)			\
      SymX(catchSTMzh_fast)			\
sof's avatar
sof committed
489
      SymX(closure_flags)                       \
490
      SymX(cmp_thread)				\
sof's avatar
sof committed
491 492
      SymX(cmpIntegerzh_fast)	        	\
      SymX(cmpIntegerIntzh_fast)	      	\
sof's avatar
sof committed
493
      SymX(complementIntegerzh_fast)		\
494 495 496 497 498
      SymX(createAdjustor)			\
      SymX(decodeDoublezh_fast)			\
      SymX(decodeFloatzh_fast)			\
      SymX(defaultsHook)			\
      SymX(delayzh_fast)			\
sof's avatar
sof committed
499 500
      SymX(deRefWeakzh_fast)			\
      SymX(deRefStablePtrzh_fast)		\
501
      SymX(dirty_MUT_VAR)			\
502 503 504
      SymX(divExactIntegerzh_fast)		\
      SymX(divModIntegerzh_fast)		\
      SymX(forkzh_fast)				\
Simon Marlow's avatar
Simon Marlow committed
505
      SymX(forkOnzh_fast)			\
506
      SymX(forkProcess)				\
507
      SymX(forkOS_createThread)			\
508
      SymX(freeHaskellFunctionPtr)		\
sof's avatar
sof committed
509
      SymX(freeStablePtr)		        \
510
      SymX(gcdIntegerzh_fast)			\
sof's avatar
sof committed
511 512
      SymX(gcdIntegerIntzh_fast)		\
      SymX(gcdIntzh_fast)			\
513
      SymX(genSymZh)				\
dons's avatar
dons committed
514
      SymX(genericRaise)			\
515 516
      SymX(getProgArgv)				\
      SymX(getStablePtr)			\
517 518 519 520 521 522 523 524
      SymX(hs_init)				\
      SymX(hs_exit)				\
      SymX(hs_set_argv)				\
      SymX(hs_add_root)				\
      SymX(hs_perform_gc)			\
      SymX(hs_free_stable_ptr)			\
      SymX(hs_free_fun_ptr)			\
      SymX(initLinker)				\
525
      SymX(int2Integerzh_fast)			\
sof's avatar
sof committed
526 527
      SymX(integer2Intzh_fast)			\
      SymX(integer2Wordzh_fast)			\
528
      SymX(isCurrentThreadBoundzh_fast)		\
529 530 531 532
      SymX(isDoubleDenormalized)		\
      SymX(isDoubleInfinite)			\
      SymX(isDoubleNaN)				\
      SymX(isDoubleNegativeZero)		\
sof's avatar
sof committed
533
      SymX(isEmptyMVarzh_fast)			\
534 535 536 537 538
      SymX(isFloatDenormalized)			\
      SymX(isFloatInfinite)			\
      SymX(isFloatNaN)				\
      SymX(isFloatNegativeZero)			\
      SymX(killThreadzh_fast)			\
dons's avatar
dons committed
539
      SymX(loadObj)          			\
540 541
      SymX(insertStableSymbol) 			\
      SymX(insertSymbol)     			\
dons's avatar
dons committed
542
      SymX(lookupSymbol)     			\
sof's avatar
sof committed
543
      SymX(makeStablePtrzh_fast)		\
544 545
      SymX(minusIntegerzh_fast)			\
      SymX(mkApUpd0zh_fast)			\
sof's avatar
sof committed
546
      SymX(myThreadIdzh_fast)			\
547
      SymX(labelThreadzh_fast)                  \
548 549 550
      SymX(newArrayzh_fast)			\
      SymX(newBCOzh_fast)			\
      SymX(newByteArrayzh_fast)			\
551
      SymX_redirect(newCAF, newDynCAF)		\
552 553
      SymX(newMVarzh_fast)			\
      SymX(newMutVarzh_fast)			\
554
      SymX(newTVarzh_fast)			\
555
      SymX(atomicModifyMutVarzh_fast)		\
556
      SymX(newPinnedByteArrayzh_fast)		\
557
      SymX(newSpark)				\
558 559
      SymX(orIntegerzh_fast)			\
      SymX(performGC)				\
560
      SymX(performMajorGC)			\
561 562 563 564 565 566 567
      SymX(plusIntegerzh_fast)			\
      SymX(prog_argc)				\
      SymX(prog_argv)				\
      SymX(putMVarzh_fast)			\
      SymX(quotIntegerzh_fast)			\
      SymX(quotRemIntegerzh_fast)		\
      SymX(raisezh_fast)			\
568
      SymX(raiseIOzh_fast)			\
569
      SymX(readTVarzh_fast)			\
570 571 572
      SymX(remIntegerzh_fast)			\
      SymX(resetNonBlockingFd)			\
      SymX(resumeThread)			\
dons's avatar
dons committed
573
      SymX(resolveObjs)                         \
574
      SymX(retryzh_fast)                        \
575 576 577 578 579
      SymX(rts_apply)				\
      SymX(rts_checkSchedStatus)		\
      SymX(rts_eval)				\
      SymX(rts_evalIO)				\
      SymX(rts_evalLazyIO)			\
580
      SymX(rts_evalStableIO)			\
581 582 583 584 585 586 587 588
      SymX(rts_eval_)				\
      SymX(rts_getBool)				\
      SymX(rts_getChar)				\
      SymX(rts_getDouble)			\
      SymX(rts_getFloat)			\
      SymX(rts_getInt)				\
      SymX(rts_getInt32)			\
      SymX(rts_getPtr)				\
589
      SymX(rts_getFunPtr)			\
590
      SymX(rts_getStablePtr)			\
591
      SymX(rts_getThreadId)			\
592 593
      SymX(rts_getWord)				\
      SymX(rts_getWord32)			\
594
      SymX(rts_lock)				\
595 596 597 598 599 600 601 602 603 604
      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)				\
605
      SymX(rts_mkFunPtr)			\
606 607 608 609 610 611 612
      SymX(rts_mkStablePtr)			\
      SymX(rts_mkString)			\
      SymX(rts_mkWord)				\
      SymX(rts_mkWord16)			\
      SymX(rts_mkWord32)			\
      SymX(rts_mkWord64)			\
      SymX(rts_mkWord8)				\
613
      SymX(rts_unlock)				\
614
      SymX(rtsSupportsBoundThreads)		\
615 616
      SymX(__hscore_get_saved_termios)		\
      SymX(__hscore_set_saved_termios)		\
617
      SymX(setProgArgv)				\
618 619
      SymX(startupHaskell)			\
      SymX(shutdownHaskell)			\
620 621 622 623
      SymX(shutdownHaskellAndExit)		\
      SymX(stable_ptr_table)			\
      SymX(stackOverflow)			\
      SymX(stg_CAF_BLACKHOLE_info)		\
624
      SymX(awakenBlockedQueue)			\
625 626 627 628
      SymX(stg_CHARLIKE_closure)		\
      SymX(stg_EMPTY_MVAR_info)			\
      SymX(stg_IND_STATIC_info)			\
      SymX(stg_INTLIKE_closure)			\
629
      SymX(stg_MUT_ARR_PTRS_DIRTY_info)		\
630
      SymX(stg_MUT_ARR_PTRS_FROZEN_info)	\
631
      SymX(stg_MUT_ARR_PTRS_FROZEN0_info)	\
632
      SymX(stg_WEAK_info)                       \
633 634 635 636 637 638 639 640 641 642
      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)			\
643
      SymX(stg_ap_pppv_info)			\
644 645 646
      SymX(stg_ap_pppp_info)			\
      SymX(stg_ap_ppppp_info)			\
      SymX(stg_ap_pppppp_info)			\
647 648 649 650 651 652 653 654 655 656 657 658 659 660 661
      SymX(stg_ap_0_fast)			\
      SymX(stg_ap_v_fast)			\
      SymX(stg_ap_f_fast)			\
      SymX(stg_ap_d_fast)			\
      SymX(stg_ap_l_fast)			\
      SymX(stg_ap_n_fast)			\
      SymX(stg_ap_p_fast)			\
      SymX(stg_ap_pv_fast)			\
      SymX(stg_ap_pp_fast)			\
      SymX(stg_ap_ppv_fast)			\
      SymX(stg_ap_ppp_fast)			\
      SymX(stg_ap_pppv_fast)			\
      SymX(stg_ap_pppp_fast)			\
      SymX(stg_ap_ppppp_fast)			\
      SymX(stg_ap_pppppp_fast)			\
662
      SymX(stg_ap_1_upd_info)			\
663 664 665 666 667 668
      SymX(stg_ap_2_upd_info)			\
      SymX(stg_ap_3_upd_info)			\
      SymX(stg_ap_4_upd_info)			\
      SymX(stg_ap_5_upd_info)			\
      SymX(stg_ap_6_upd_info)			\
      SymX(stg_ap_7_upd_info)			\
669
      SymX(stg_exit)				\
670
      SymX(stg_sel_0_upd_info)			\
671 672 673 674 675 676
      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)			\
677 678 679 680 681 682 683 684 685
      SymX(stg_sel_1_upd_info)			\
      SymX(stg_sel_2_upd_info)			\
      SymX(stg_sel_3_upd_info)			\
      SymX(stg_sel_4_upd_info)			\
      SymX(stg_sel_5_upd_info)			\
      SymX(stg_sel_6_upd_info)			\
      SymX(stg_sel_7_upd_info)			\
      SymX(stg_sel_8_upd_info)			\
      SymX(stg_sel_9_upd_info)			\
686 687
      SymX(stg_upd_frame_info)			\
      SymX(suspendThread)			\
688
      SymX(takeMVarzh_fast)			\
689
      SymX(timesIntegerzh_fast)			\
690
      SymX(tryPutMVarzh_fast)			\
691 692
      SymX(tryTakeMVarzh_fast)			\
      SymX(unblockAsyncExceptionszh_fast)	\
dons's avatar
dons committed
693
      SymX(unloadObj)                           \
694
      SymX(unsafeThawArrayzh_fast)		\
695 696
      SymX(waitReadzh_fast)			\
      SymX(waitWritezh_fast)			\
697
      SymX(word2Integerzh_fast)			\
698
      SymX(writeTVarzh_fast)			\
699
      SymX(xorIntegerzh_fast)			\
sof's avatar
sof committed
700
      SymX(yieldzh_fast)                        \
701 702 703 704 705 706 707 708 709 710 711 712 713
      SymX(stg_interp_constr_entry)             \
      SymX(stg_interp_constr1_entry)            \
      SymX(stg_interp_constr2_entry)            \
      SymX(stg_interp_constr3_entry)            \
      SymX(stg_interp_constr4_entry)            \
      SymX(stg_interp_constr5_entry)            \
      SymX(stg_interp_constr6_entry)            \
      SymX(stg_interp_constr7_entry)            \
      SymX(stg_interp_constr8_entry)            \
      SymX(stgMallocBytesRWX)                   \
      SymX(getAllocations)                      \
      SymX(revertCAFs)                          \
      SymX(RtsFlags)                            \
sof's avatar
sof committed
714
      RTS_USER_SIGNALS_SYMBOLS
715

716
#ifdef SUPPORT_LONG_LONGS
717
#define RTS_LONG_LONG_SYMS			\
718 719
      SymX(int64ToIntegerzh_fast)		\
      SymX(word64ToIntegerzh_fast)
720 721 722 723
#else
#define RTS_LONG_LONG_SYMS /* nothing */
#endif

724 725 726
// 64-bit support functions in libgcc.a
#if defined(__GNUC__) && SIZEOF_VOID_P <= 4
#define RTS_LIBGCC_SYMBOLS			\
727 728 729
      Sym(__divdi3)                             \
      Sym(__udivdi3)                            \
      Sym(__moddi3)                             \
730
      Sym(__umoddi3)				\
731
      Sym(__muldi3)				\
732 733 734 735
      Sym(__ashldi3)				\
      Sym(__ashrdi3)				\
      Sym(__lshrdi3)				\
      Sym(__eprintf)
736
#elif defined(ia64_HOST_ARCH)
737 738 739 740 741 742 743
#define RTS_LIBGCC_SYMBOLS			\
      Sym(__divdi3)				\
      Sym(__udivdi3)                            \
      Sym(__moddi3)				\
      Sym(__umoddi3)				\
      Sym(__divsf3)				\
      Sym(__divdf3)
744 745 746 747
#else
#define RTS_LIBGCC_SYMBOLS
#endif

748
#if defined(darwin_HOST_OS) && defined(powerpc_HOST_ARCH)
749 750 751 752 753 754
      // 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)
755
#endif
756 757

/* entirely bogus claims about types of these symbols */
758
#define Sym(vvv)  extern void vvv(void);
759
#define SymX(vvv) /**/
760
#define SymX_redirect(vvv,xxx) /**/
761
RTS_SYMBOLS
762
RTS_RET_SYMBOLS
763
RTS_LONG_LONG_SYMS
764
RTS_POSIX_ONLY_SYMBOLS
765
RTS_MINGW_ONLY_SYMBOLS
sof's avatar
sof committed
766
RTS_CYGWIN_ONLY_SYMBOLS
767
RTS_DARWIN_ONLY_SYMBOLS
768
RTS_LIBGCC_SYMBOLS
769 770
#undef Sym
#undef SymX
771
#undef SymX_redirect
772 773 774 775 776 777 778 779 780 781 782

#ifdef LEADING_UNDERSCORE
#define MAYBE_LEADING_UNDERSCORE_STR(s) ("_" s)
#else
#define MAYBE_LEADING_UNDERSCORE_STR(s) (s)
#endif

#define Sym(vvv) { MAYBE_LEADING_UNDERSCORE_STR(#vvv), \
                    (void*)(&(vvv)) },
#define SymX(vvv) Sym(vvv)

783 784 785 786 787 788
// 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)) },

789
static RtsSymbolVal rtsSyms[] = {
790
      RTS_SYMBOLS
791
      RTS_RET_SYMBOLS
792
      RTS_LONG_LONG_SYMS
793
      RTS_POSIX_ONLY_SYMBOLS
794
      RTS_MINGW_ONLY_SYMBOLS
sof's avatar
sof committed
795
      RTS_CYGWIN_ONLY_SYMBOLS
796
      RTS_LIBGCC_SYMBOLS
797 798 799 800
#if defined(darwin_HOST_OS) && defined(i386_HOST_ARCH)
      // dyld stub code contains references to this,
      // but it should never be called because we treat
      // lazy pointers as nonlazy.
801
      { "dyld_stub_binding_helper", (void*)0xDEADBEEF },
802
#endif
803 804 805
      { 0, 0 } /* sentinel */
};

806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894

/* -----------------------------------------------------------------------------
 * Utilities for handling root pointers.
 * -------------------------------------------------------------------------- */


#define INIT_RPT_SIZE 64

STATIC_INLINE void
initFreeList(rootEntry *table, nat n, rootEntry *free)
{
  rootEntry *p;

  for (p = table + n - 1; p >= table; p--) {
    p->addr   = (P_)free;
    free = p;
  }
  root_ptr_free = table;
}

void
initRootPtrTable(void)
{
  if (RPT_size > 0)
    return;

  RPT_size = INIT_RPT_SIZE;
  root_ptr_table = stgMallocBytes(RPT_size * sizeof(rootEntry),
                                    "initRootPtrTable");

  initFreeList(root_ptr_table,INIT_RPT_SIZE,NULL);
}


void
enlargeRootPtrTable(void)
{
  nat old_RPT_size = RPT_size;

  // 2nd and subsequent times
  RPT_size *= 2;
  root_ptr_table =
    stgReallocBytes(root_ptr_table,
                    RPT_size * sizeof(rootEntry),
                    "enlargeRootPtrTable");

  initFreeList(root_ptr_table + old_RPT_size, old_RPT_size, NULL);
}

static void
addRootObject(void *addr)
{
  StgWord rt;

  if (root_ptr_free == NULL) {
    enlargeRootPtrTable();
  }

  rt = root_ptr_free - root_ptr_table;
  root_ptr_free  = (rootEntry*)(root_ptr_free->addr);
  root_ptr_table[rt].addr = addr;
}

/* -----------------------------------------------------------------------------
 * Treat root pointers as roots for the garbage collector.
 * -------------------------------------------------------------------------- */

void
markRootPtrTable(evac_fn evac)
{
  rootEntry *p, *end_root_ptr_table;
  StgPtr q;

  end_root_ptr_table = &root_ptr_table[RPT_size];

  for (p = root_ptr_table; p < end_root_ptr_table; p++) {
    q = p->addr;

    if (q && (q < (P_)root_ptr_table || q >= (P_)end_root_ptr_table)) {
        evac((StgClosure **)p->addr);
    }
  }
}

/* -----------------------------------------------------------------------------
 * End of utilities for handling root pointers.
 * -------------------------------------------------------------------------- */


895 896 897 898 899
/* -----------------------------------------------------------------------------
 * Insert symbols into hash tables, checking for duplicates.
 */
static void ghciInsertStrHashTable ( char* obj_name,
                                     HashTable *table,
900
                                     char* key,
901 902 903 904 905 906 907 908
                                     void *data
				   )
{
   if (lookupHashTable(table, (StgWord)key) == NULL)
   {
      insertStrHashTable(table, (StgWord)key, data);
      return;
   }
909
   debugBelch(
910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928
      "\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);
}


929 930 931
/* -----------------------------------------------------------------------------
 * initialize the object linker
 */
932 933 934 935


static int linker_init_done = 0 ;

936
#if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
937
static void *dl_prog_handle;
938
#endif
939

dons's avatar
dons committed
940
/* dlopen(NULL,..) doesn't work so we grab libc explicitly */
941
#if defined(openbsd_HOST_OS)
dons's avatar
dons committed
942 943 944
static void *dl_libc_handle;
#endif

945 946 947
void
initLinker( void )
{
948
    RtsSymbolVal *sym;
949

950 951 952 953 954 955 956
    /* 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;
    }

957 958
    initRootPtrTable();
    stablehash = allocStrHashTable();
959 960 961 962
    symhash = allocStrHashTable();

    /* populate the symbol table with stuff from the RTS */
    for (sym = rtsSyms; sym->lbl != NULL; sym++) {
963 964
	ghciInsertStrHashTable("(GHCi built-in symbols)",
                               symhash, sym->lbl, sym->addr);
965
    }
966
#   if defined(OBJFORMAT_MACHO) && defined(powerpc_HOST_ARCH)
967 968 969
    machoInitSymbolsWithoutUnderscore();
#   endif

970
#   if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
971
#   if defined(RTLD_DEFAULT)
972 973
    dl_prog_handle = RTLD_DEFAULT;
#   else
974
    dl_prog_handle = dlopen(NULL, RTLD_LAZY);
975
#   if defined(openbsd_HOST_OS)
dons's avatar
dons committed
976 977
    dl_libc_handle = dlopen("libc.so", RTLD_LAZY);
#   endif
978
#   endif /* RTLD_DEFAULT */
979
#   endif
980 981
}

982
/* -----------------------------------------------------------------------------
983 984 985
 *                  Loading DLL or .so dynamic libraries
 * -----------------------------------------------------------------------------
 *
986 987 988 989
 * 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
990 991
 * dl-handle.  Returns NULL if success, otherwise ptr to an err msg.
 *
992
 * In the PEi386 case, open the DLLs and put handles to them in a
993
 * linked list.  When looking for a symbol, try all handles in the
994 995 996 997 998
 * 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.
999
 *
1000
 */
1001 1002 1003 1004 1005 1006

#if defined(OBJFORMAT_PEi386)
/* A record for storing handles into DLLs. */

typedef
   struct _OpenedDLL {
1007
      char*              name;
1008 1009
      struct _OpenedDLL* next;
      HINSTANCE instance;
1010
   }
1011 1012 1013 1014 1015 1016
   OpenedDLL;

/* A list thereof. */
static OpenedDLL* opened_dlls = NULL;
#endif

1017 1018
char *
addDLL( char *dll_name )
1019
{
1020
#  if defined(OBJFORMAT_ELF) || defined(OBJFORMAT_MACHO)
1021
   /* ------------------- ELF DLL loader ------------------- */
1022
   void *hdl;
1023
   char *errmsg;
1024

1025 1026
   initLinker();

1027
   hdl= dlopen(dll_name, RTLD_NOW | RTLD_GLOBAL);
dons's avatar
dons committed
1028

1029 1030 1031 1032 1033 1034 1035 1036
   if (hdl == NULL) {
      /* dlopen failed; return a ptr to the error msg. */
      errmsg = dlerror();
      if (errmsg == NULL) errmsg = "addDLL: unknown error";
      return errmsg;
   } else {
      return NULL;
   }
1037 1038
   /*NOTREACHED*/

1039
#  elif defined(OBJFORMAT_PEi386)
1040
   /* ------------------- Win32 DLL loader ------------------- */
1041

1042
   char*      buf;
1043
   OpenedDLL* o_dll;
1044
   HINSTANCE  instance;
1045

1046 1047
   initLinker();

1048
   /* debugBelch("\naddDLL; dll_name = `%s'\n", dll_name); */
1049 1050 1051 1052 1053

   /* See if we've already got it, and ignore if so. */
   for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
      if (0 == strcmp(o_dll->name, dll_name))
         return NULL;
1054 1055
   }

1056 1057 1058 1059 1060 1061 1062 1063 1064 1065
   /* 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. */

1066
   buf = stgMallocBytes(strlen(dll_name) + 10, "addDLL");
1067 1068 1069
   sprintf(buf, "%s.DLL", dll_name);
   instance = LoadLibrary(buf);
   if (instance == NULL) {
1070
	 sprintf(buf, "%s.DRV", dll_name);	// KAA: allow loading of drivers (like winspool.drv)
1071 1072
	 instance = LoadLibrary(buf);
	 if (instance == NULL) {
sof's avatar
sof committed
1073
		stgFree(buf);
1074 1075 1076 1077

	    /* LoadLibrary failed; return a ptr to the error msg. */
	    return "addDLL: unknown error";
   	 }
1078
   }
sof's avatar
sof committed
1079
   stgFree(buf);
1080

1081
   /* Add this DLL to the list of DLLs in which to search for symbols. */
1082
   o_dll = stgMallocBytes( sizeof(OpenedDLL), "addDLL" );
1083 1084
   o_dll->name     = stgMallocBytes(1+strlen(dll_name), "addDLL");
   strcpy(o_dll->name, dll_name);
1085
   o_dll->instance = instance;
1086 1087
   o_dll->next     = opened_dlls;
   opened_dlls     = o_dll;
1088 1089

   return NULL;
1090 1091 1092 1093 1094
#  else
   barf("addDLL: not implemented on this platform");
#  endif
}

1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114
/* -----------------------------------------------------------------------------
 * insert a stable symbol in the hash table
 */

void
insertStableSymbol(char* obj_name, char* key, StgPtr p)
{
  ghciInsertStrHashTable(obj_name, stablehash, key, getStablePtr(p));
}


/* -----------------------------------------------------------------------------
 * insert a symbol in the hash table
 */
void
insertSymbol(char* obj_name, char* key, void* data)
{
  ghciInsertStrHashTable(obj_name, symhash, key, data);
}

1115 1116
/* -----------------------------------------------------------------------------
 * lookup a symbol in the hash table
1117
 */
1118 1119 1120
void *
lookupSymbol( char *lbl )
{
1121
    void *val;
1122
    initLinker() ;
1123
    ASSERT(symhash != NULL);
1124 1125 1126
    val = lookupStrHashTable(symhash, lbl);

    if (val == NULL) {
1127
#       if defined(OBJFORMAT_ELF)
1128
#	if defined(openbsd_HOST_OS)
dons's avatar
dons committed
1129 1130
	val = dlsym(dl_prog_handle, lbl);
	return (val != NULL) ? val : dlsym(dl_libc_handle,lbl);
1131 1132 1133 1134 1135 1136 1137 1138 1139 1140
#	elif defined(x86_64_HOST_ARCH)
	val = dlsym(dl_prog_handle, lbl);
	if (val >= (void *)0x80000000) {
	    void *new_val;
	    new_val = x86_64_high_symbol(lbl, val);
	    IF_DEBUG(linker,debugBelch("lookupSymbol: relocating out of range symbol: %s = %p, now %p\n", lbl, val, new_val));
	    return new_val;
	} else {
	    return val;
	}
dons's avatar
dons committed
1141
#	else /* not openbsd */
1142
	return dlsym(dl_prog_handle, lbl);
dons's avatar
dons committed
1143
#	endif
1144 1145 1146 1147 1148 1149 1150
#       elif defined(OBJFORMAT_MACHO)
	if(NSIsSymbolNameDefined(lbl)) {
	    NSSymbol symbol = NSLookupAndBindSymbol(lbl);
	    return NSAddressOfSymbol(symbol);
	} else {
	    return NULL;
	}
1151
#       elif defined(OBJFORMAT_PEi386)
1152 1153 1154
        OpenedDLL* o_dll;
        void* sym;
        for (o_dll = opened_dlls; o_dll != NULL; o_dll = o_dll->next) {
1155
	  /* debugBelch("look in %s for %s\n", o_dll->name, lbl); */
1156 1157 1158 1159 1160 1161 1162
           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));
sof's avatar
sof committed
1163
              if (sym != NULL) {
1164
		/*debugBelch("found %s in %s\n", lbl+1,o_dll->name);*/