tccrun.c

   1 /*
   2  *  TCC - Tiny C Compiler - Support for -run switch
   3  *
   4  *  Copyright (c) 2001-2004 Fabrice Bellard
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20
  21 #include "tcc.h"
  22
  23 #ifdef _WIN32
  24 #define ucontext_t CONTEXT
  25 #endif
  26
  27 static void set_pages_executable(void *ptr, unsigned long length);
  28 static void set_exception_handler(void);
  29 static int rt_get_caller_pc(uplong *paddr, ucontext_t *uc, int level);
  30 static void rt_error(ucontext_t *uc, const char *fmt, ...);
  31 static int tcc_relocate_ex(TCCState *s1, void *ptr);
  32
  33 #ifdef _WIN64
  34 static void win64_add_function_table(TCCState *s1);
  35 #endif
  36
  37 /* ------------------------------------------------------------- */
  38 /* Do all relocations (needed before using tcc_get_symbol())
  39    Returns -1 on error. */
  40
  41 int tcc_relocate(TCCState *s1)
  42 {
  43     int ret;
  44 #ifdef HAVE_SELINUX
  45     /* Use mmap instead of malloc for Selinux
  46     Ref http://www.gnu.org/s/libc/manual/html_node/File-Size.html */
  47     char tmpfname[] = "/tmp/.tccrunXXXXXX";
  48     int fd = mkstemp (tmpfname);
  49     if ((ret= tcc_relocate_ex(s1,NULL)) < 0)return -1;
  50     s1->mem_size=ret;
  51     unlink (tmpfname); ftruncate (fd, s1->mem_size);
  52     s1->write_mem = mmap (NULL, ret, PROT_READ|PROT_WRITE,
  53         MAP_SHARED, fd, 0);
  54     if(s1->write_mem == MAP_FAILED){
  55         error("/tmp not writeable");
  56         return -1;
  57     }
  58     s1->runtime_mem = mmap (NULL, ret, PROT_READ|PROT_EXEC,
  59         MAP_SHARED, fd, 0);
  60     if(s1->runtime_mem == MAP_FAILED){
  61         error("/tmp not executable");
  62         return -1;
  63     }
  64     ret = tcc_relocate_ex(s1, s1->write_mem);
  65 #else
  66     ret = tcc_relocate_ex(s1, NULL);
  67     if (-1 != ret) {
  68         s1->runtime_mem = tcc_malloc(ret);
  69         ret = tcc_relocate_ex(s1, s1->runtime_mem);
  70     }
  71 #endif
  72     return ret;
  73 }
  74
  75 /* launch the compiled program with the given arguments */
  76 int tcc_run(TCCState *s1, int argc, char **argv)
  77 {
  78     int (*prog_main)(int, char **);
  79
  80     if (tcc_relocate(s1) < 0)
  81         return -1;
  82
  83     prog_main = tcc_get_symbol_err(s1, "main");
  84
  85 #ifdef CONFIG_TCC_BACKTRACE
  86     if (s1->do_debug)
  87         set_exception_handler();
  88 #endif
  89
  90 #ifdef CONFIG_TCC_BCHECK
  91     if (s1->do_bounds_check) {
  92         void (*bound_init)(void);
  93         void (*bound_exit)(void);
  94         int ret;
  95         /* set error function */
  96         rt_bound_error_msg = tcc_get_symbol_err(s1, "__bound_error_msg");
  97         rt_prog_main = prog_main;
  98         /* XXX: use .init section so that it also work in binary ? */
  99         bound_init = tcc_get_symbol_err(s1, "__bound_init");
 100         bound_exit = tcc_get_symbol_err(s1, "__bound_exit");
 101         bound_init();
 102         ret = (*prog_main)(argc, argv);
 103         bound_exit();
 104         return ret;
 105     }
 106 #endif
 107
 108 #ifdef TCC_TARGET_PE
 109     {
 110       unsigned char *p = tcc_get_symbol(s1, "tinyc_no_getbp");
 111       if (p) *p = 0;
 112     }
 113 #endif
 114     return (*prog_main)(argc, argv);
 115 }
 116
 117
 118 /* relocate code. Return -1 on error, required size if ptr is NULL,
 119    otherwise copy code into buffer passed by the caller */
 120 static int tcc_relocate_ex(TCCState *s1, void *ptr)
 121 {
 122     Section *s;
 123     unsigned long offset, length;
 124     uplong mem;
 125     int i;
 126
 127     if (0 == s1->runtime_added) {
 128         s1->runtime_added = 1;
 129         s1->nb_errors = 0;
 130 #ifdef TCC_TARGET_PE
 131         pe_output_file(s1, NULL);
 132 #else
 133         tcc_add_runtime(s1);
 134         relocate_common_syms();
 135         tcc_add_linker_symbols(s1);
 136         build_got_entries(s1);
 137 #endif
 138         if (s1->nb_errors)
 139             return -1;
 140     }
 141
 142     offset = 0, mem = (uplong)ptr;
 143     for(i = 1; i < s1->nb_sections; i++) {
 144         s = s1->sections[i];
 145         if (0 == (s->sh_flags & SHF_ALLOC))
 146             continue;
 147         length = s->data_offset;
 148         s->sh_addr = mem ? (mem + offset + 15) & ~15 : 0;
 149         offset = (offset + length + 15) & ~15;
 150     }
 151     offset += 16;
 152
 153     /* relocate symbols */
 154     relocate_syms(s1, 1);
 155     if (s1->nb_errors)
 156         return -1;
 157
 158 #if (defined TCC_TARGET_X86_64 || defined TCC_TARGET_ARM) && !defined TCC_TARGET_PE
 159     s1->runtime_plt_and_got_offset = 0;
 160     s1->runtime_plt_and_got = (char *)(mem + offset);
 161     /* double the size of the buffer for got and plt entries
 162        XXX: calculate exact size for them? */
 163     offset *= 2;
 164 #endif
 165
 166     if (0 == mem)
 167         return offset;
 168
 169     /* relocate each section */
 170     for(i = 1; i < s1->nb_sections; i++) {
 171         s = s1->sections[i];
 172         if (s->reloc)
 173             relocate_section(s1, s);
 174     }
 175
 176     for(i = 1; i < s1->nb_sections; i++) {
 177         s = s1->sections[i];
 178         if (0 == (s->sh_flags & SHF_ALLOC))
 179             continue;
 180         length = s->data_offset;
 181         // printf("%-12s %08x %04x\n", s->name, s->sh_addr, length);
 182         ptr = (void*)(uplong)s->sh_addr;
 183         if (NULL == s->data || s->sh_type == SHT_NOBITS)
 184             memset(ptr, 0, length);
 185         else
 186             memcpy(ptr, s->data, length);
 187         /* mark executable sections as executable in memory */
 188         if (s->sh_flags & SHF_EXECINSTR)
 189             set_pages_executable(ptr, length);
 190     }
 191
 192 #if (defined TCC_TARGET_X86_64 || defined TCC_TARGET_ARM) && !defined TCC_TARGET_PE
 193     set_pages_executable(s1->runtime_plt_and_got,
 194                          s1->runtime_plt_and_got_offset);
 195 #endif
 196
 197 #ifdef _WIN64
 198     win64_add_function_table(s1);
 199 #endif
 200     return 0;
 201 }
 202
 203 /* ------------------------------------------------------------- */
 204 /* allow to run code in memory */
 205
 206 static void set_pages_executable(void *ptr, unsigned long length)
 207 {
 208 #ifdef _WIN32
 209     unsigned long old_protect;
 210     VirtualProtect(ptr, length, PAGE_EXECUTE_READWRITE, &old_protect);
 211 #else
 212     unsigned long start, end;
 213     start = (uplong)ptr & ~(PAGESIZE - 1);
 214     end = (uplong)ptr + length;
 215     end = (end + PAGESIZE - 1) & ~(PAGESIZE - 1);
 216     mprotect((void *)start, end - start, PROT_READ | PROT_WRITE | PROT_EXEC);
 217 #endif
 218 }
 219
 220 /* ------------------------------------------------------------- */
 221 #ifdef CONFIG_TCC_BACKTRACE
 222
 223 /* print the position in the source file of PC value 'pc' by reading
 224    the stabs debug information */
 225 static uplong rt_printline(uplong wanted_pc, const char *msg)
 226 {
 227     Stab_Sym *sym, *sym_end;
 228     char func_name[128], last_func_name[128];
 229     unsigned long func_addr, last_pc, pc;
 230     const char *incl_files[INCLUDE_STACK_SIZE];
 231     int incl_index, len, last_line_num, i;
 232     const char *str, *p;
 233
 234     func_name[0] = '\0';
 235     func_addr = 0;
 236     incl_index = 0;
 237     last_func_name[0] = '\0';
 238     last_pc = 0xffffffff;
 239     last_line_num = 1;
 240     sym = (Stab_Sym *)stab_section->data + 1;
 241     sym_end = (Stab_Sym *)(stab_section->data + stab_section->data_offset);
 242     while (sym < sym_end) {
 243         switch(sym->n_type) {
 244             /* function start or end */
 245         case N_FUN:
 246             if (sym->n_strx == 0) {
 247                 /* we test if between last line and end of function */
 248                 pc = sym->n_value + func_addr;
 249                 if (wanted_pc >= last_pc && wanted_pc < pc)
 250                     goto found;
 251                 func_name[0] = '\0';
 252                 func_addr = 0;
 253             } else {
 254                 str = stabstr_section->data + sym->n_strx;
 255                 p = strchr(str, ':');
 256                 if (!p) {
 257                     pstrcpy(func_name, sizeof(func_name), str);
 258                 } else {
 259                     len = p - str;
 260                     if (len > sizeof(func_name) - 1)
 261                         len = sizeof(func_name) - 1;
 262                     memcpy(func_name, str, len);
 263                     func_name[len] = '\0';
 264                 }
 265                 func_addr = sym->n_value;
 266             }
 267             break;
 268             /* line number info */
 269         case N_SLINE:
 270             pc = sym->n_value + func_addr;
 271             if (wanted_pc >= last_pc && wanted_pc < pc)
 272                 goto found;
 273             last_pc = pc;
 274             last_line_num = sym->n_desc;
 275             /* XXX: slow! */
 276             strcpy(last_func_name, func_name);
 277             break;
 278             /* include files */
 279         case N_BINCL:
 280             str = stabstr_section->data + sym->n_strx;
 281         add_incl:
 282             if (incl_index < INCLUDE_STACK_SIZE) {
 283                 incl_files[incl_index++] = str;
 284             }
 285             break;
 286         case N_EINCL:
 287             if (incl_index > 1)
 288                 incl_index--;
 289             break;
 290         case N_SO:
 291             if (sym->n_strx == 0) {
 292                 incl_index = 0; /* end of translation unit */
 293             } else {
 294                 str = stabstr_section->data + sym->n_strx;
 295                 /* do not add path */
 296                 len = strlen(str);
 297                 if (len > 0 && str[len - 1] != '/')
 298                     goto add_incl;
 299             }
 300             break;
 301         }
 302         sym++;
 303     }
 304
 305     /* second pass: we try symtab symbols (no line number info) */
 306     incl_index = 0;
 307     {
 308         ElfW(Sym) *sym, *sym_end;
 309         int type;
 310
 311         sym_end = (ElfW(Sym) *)(symtab_section->data + symtab_section->data_offset);
 312         for(sym = (ElfW(Sym) *)symtab_section->data + 1;
 313             sym < sym_end;
 314             sym++) {
 315             type = ELFW(ST_TYPE)(sym->st_info);
 316             if (type == STT_FUNC || type == STT_GNU_IFUNC) {
 317                 if (wanted_pc >= sym->st_value &&
 318                     wanted_pc < sym->st_value + sym->st_size) {
 319                     pstrcpy(last_func_name, sizeof(last_func_name),
 320                             strtab_section->data + sym->st_name);
 321                     func_addr = sym->st_value;
 322                     goto found;
 323                 }
 324             }
 325         }
 326     }
 327     /* did not find any info: */
 328     fprintf(stderr, "%s %p ???\n", msg, (void*)wanted_pc);
 329     fflush(stderr);
 330     return 0;
 331  found:
 332     i = incl_index;
 333     if (i > 0)
 334         fprintf(stderr, "%s:%d: ", incl_files[--i], last_line_num);
 335     fprintf(stderr, "%s %p", msg, (void*)wanted_pc);
 336     if (last_func_name[0] != '\0')
 337         fprintf(stderr, " %s()", last_func_name);
 338     if (--i >= 0) {
 339         fprintf(stderr, " (included from ");
 340         for (;;) {
 341             fprintf(stderr, "%s", incl_files[i]);
 342             if (--i < 0)
 343                 break;
 344             fprintf(stderr, ", ");
 345         }
 346         fprintf(stderr, ")");
 347     }
 348     fprintf(stderr, "\n");
 349     fflush(stderr);
 350     return func_addr;
 351 }
 352
 353 /* emit a run time error at position 'pc' */
 354 static void rt_error(ucontext_t *uc, const char *fmt, ...)
 355 {
 356     va_list ap;
 357     uplong pc;
 358     int i;
 359
 360     va_start(ap, fmt);
 361     fprintf(stderr, "Runtime error: ");
 362     vfprintf(stderr, fmt, ap);
 363     fprintf(stderr, "\n");
 364
 365     for(i=0;i<num_callers;i++) {
 366         if (rt_get_caller_pc(&pc, uc, i) < 0)
 367             break;
 368         pc = rt_printline(pc, i ? "by" : "at");
 369         if (pc == (uplong)rt_prog_main && pc)
 370             break;
 371     }
 372     exit(255);
 373     va_end(ap);
 374 }
 375
 376 /* ------------------------------------------------------------- */
 377 #ifndef _WIN32
 378
 379 /* signal handler for fatal errors */
 380 static void sig_error(int signum, siginfo_t *siginf, void *puc)
 381 {
 382     ucontext_t *uc = puc;
 383
 384     switch(signum) {
 385     case SIGFPE:
 386         switch(siginf->si_code) {
 387         case FPE_INTDIV:
 388         case FPE_FLTDIV:
 389             rt_error(uc, "division by zero");
 390             break;
 391         default:
 392             rt_error(uc, "floating point exception");
 393             break;
 394         }
 395         break;
 396     case SIGBUS:
 397     case SIGSEGV:
 398         if (rt_bound_error_msg && *rt_bound_error_msg)
 399             rt_error(uc, *rt_bound_error_msg);
 400         else
 401             rt_error(uc, "dereferencing invalid pointer");
 402         break;
 403     case SIGILL:
 404         rt_error(uc, "illegal instruction");
 405         break;
 406     case SIGABRT:
 407         rt_error(uc, "abort() called");
 408         break;
 409     default:
 410         rt_error(uc, "caught signal %d", signum);
 411         break;
 412     }
 413     exit(255);
 414 }
 415
 416 /* Generate a stack backtrace when a CPU exception occurs. */
 417 static void set_exception_handler(void)
 418 {
 419     struct sigaction sigact;
 420     /* install TCC signal handlers to print debug info on fatal
 421        runtime errors */
 422     sigact.sa_flags = SA_SIGINFO | SA_RESETHAND;
 423     sigact.sa_sigaction = sig_error;
 424     sigemptyset(&sigact.sa_mask);
 425     sigaction(SIGFPE, &sigact, NULL);
 426     sigaction(SIGILL, &sigact, NULL);
 427     sigaction(SIGSEGV, &sigact, NULL);
 428     sigaction(SIGBUS, &sigact, NULL);
 429     sigaction(SIGABRT, &sigact, NULL);
 430 }
 431
 432 /* ------------------------------------------------------------- */
 433 #ifdef __i386__
 434
 435 /* fix for glibc 2.1 */
 436 #ifndef REG_EIP
 437 #define REG_EIP EIP
 438 #define REG_EBP EBP
 439 #endif
 440
 441 /* return the PC at frame level 'level'. Return non zero if not found */
 442 static int rt_get_caller_pc(unsigned long *paddr, ucontext_t *uc, int level)
 443 {
 444     unsigned long fp;
 445     int i;
 446
 447     if (level == 0) {
 448 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 449         *paddr = uc->uc_mcontext.mc_eip;
 450 #elif defined(__dietlibc__)
 451         *paddr = uc->uc_mcontext.eip;
 452 #else
 453         *paddr = uc->uc_mcontext.gregs[REG_EIP];
 454 #endif
 455         return 0;
 456     } else {
 457 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 458         fp = uc->uc_mcontext.mc_ebp;
 459 #elif defined(__dietlibc__)
 460         fp = uc->uc_mcontext.ebp;
 461 #else
 462         fp = uc->uc_mcontext.gregs[REG_EBP];
 463 #endif
 464         for(i=1;i<level;i++) {
 465             /* XXX: check address validity with program info */
 466             if (fp <= 0x1000 || fp >= 0xc0000000)
 467                 return -1;
 468             fp = ((unsigned long *)fp)[0];
 469         }
 470         *paddr = ((unsigned long *)fp)[1];
 471         return 0;
 472     }
 473 }
 474
 475 /* ------------------------------------------------------------- */
 476 #elif defined(__x86_64__)
 477
 478 /* return the PC at frame level 'level'. Return non zero if not found */
 479 static int rt_get_caller_pc(unsigned long *paddr,
 480                             ucontext_t *uc, int level)
 481 {
 482     unsigned long fp;
 483     int i;
 484
 485     if (level == 0) {
 486         /* XXX: only support linux */
 487 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 488         *paddr = uc->uc_mcontext.mc_rip;
 489 #else
 490         *paddr = uc->uc_mcontext.gregs[REG_RIP];
 491 #endif
 492         return 0;
 493     } else {
 494 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 495         fp = uc->uc_mcontext.mc_rbp;
 496 #else
 497         fp = uc->uc_mcontext.gregs[REG_RBP];
 498 #endif
 499         for(i=1;i<level;i++) {
 500             /* XXX: check address validity with program info */
 501             if (fp <= 0x1000)
 502                 return -1;
 503             fp = ((unsigned long *)fp)[0];
 504         }
 505         *paddr = ((unsigned long *)fp)[1];
 506         return 0;
 507     }
 508 }
 509
 510 /* ------------------------------------------------------------- */
 511 #elif defined(__arm__)
 512
 513 /* return the PC at frame level 'level'. Return negative if not found */
 514 static int rt_get_caller_pc(unsigned long *paddr,
 515                             ucontext_t *uc, int level)
 516 {
 517     uint32_t fp, sp;
 518     int i;
 519
 520     if (level == 0) {
 521         /* XXX: only supports linux */
 522 #if defined(__linux__)
 523         *paddr = uc->uc_mcontext.arm_pc;
 524 #else
 525         return -1;
 526 #endif
 527         return 0;
 528     } else {
 529 #if defined(__linux__)
 530         fp = uc->uc_mcontext.arm_fp;
 531         sp = uc->uc_mcontext.arm_sp;
 532         if (sp < 0x1000)
 533             sp = 0x1000;
 534 #else
 535         return -1;
 536 #endif
 537         /* XXX: specific to tinycc stack frames */
 538         if (fp < sp + 12 || fp & 3)
 539             return -1;
 540         for(i = 1; i < level; i++) {
 541             sp = ((uint32_t *)fp)[-2];
 542             if (sp < fp || sp - fp > 16 || sp & 3)
 543                 return -1;
 544             fp = ((uint32_t *)fp)[-3];
 545             if (fp <= sp || fp - sp < 12 || fp & 3)
 546                 return -1;
 547         }
 548         /* XXX: check address validity with program info */
 549         *paddr = ((uint32_t *)fp)[-1];
 550         return 0;
 551     }
 552 }
 553
 554 /* ------------------------------------------------------------- */
 555 #else
 556
 557 #warning add arch specific rt_get_caller_pc()
 558 static int rt_get_caller_pc(unsigned long *paddr,
 559                             ucontext_t *uc, int level)
 560 {
 561     return -1;
 562 }
 563
 564 #endif /* !__i386__ */
 565
 566 /* ------------------------------------------------------------- */
 567 #else /* WIN32 */
 568
 569 static long __stdcall cpu_exception_handler(EXCEPTION_POINTERS *ex_info)
 570 {
 571     CONTEXT *uc = ex_info->ContextRecord;
 572 /*
 573     EXCEPTION_RECORD *er = ex_info->ExceptionRecord;
 574     printf("CPU exception: code=%08lx addr=%p\n",
 575         er->ExceptionCode, er->ExceptionAddress);
 576 */
 577     if (rt_bound_error_msg && *rt_bound_error_msg)
 578         rt_error(uc, *rt_bound_error_msg);
 579     else
 580         rt_error(uc, "dereferencing invalid pointer");
 581     exit(255);
 582     //return EXCEPTION_CONTINUE_SEARCH;
 583 }
 584
 585 /* Generate a stack backtrace when a CPU exception occurs. */
 586 static void set_exception_handler(void)
 587 {
 588     SetUnhandledExceptionFilter(cpu_exception_handler);
 589 }
 590
 591 #ifdef _WIN64
 592 static void win64_add_function_table(TCCState *s1)
 593 {
 594     RtlAddFunctionTable(
 595         (RUNTIME_FUNCTION*)(uplong)s1->uw_pdata->sh_addr,
 596         s1->uw_pdata->data_offset / sizeof (RUNTIME_FUNCTION),
 597         (uplong)text_section->sh_addr
 598         );
 599 }
 600 #endif
 601
 602 #ifdef _WIN64
 603 #define Eip Rip
 604 #define Ebp Rbp
 605 #endif
 606
 607 /* return the PC at frame level 'level'. Return non zero if not found */
 608 static int rt_get_caller_pc(uplong *paddr, CONTEXT *uc, int level)
 609 {
 610     uplong fp;
 611     int i;
 612
 613     if (level == 0) {
 614         *paddr = uc->Eip;
 615         return 0;
 616     } else {
 617         fp = uc->Ebp;
 618         for(i=1;i<level;i++) {
 619             /* XXX: check address validity with program info */
 620             if (fp <= 0x1000 || fp >= 0xc0000000)
 621                 return -1;
 622             fp = ((uplong*)fp)[0];
 623         }
 624         *paddr = ((uplong*)fp)[1];
 625         return 0;
 626     }
 627 }
 628
 629 #undef Eip
 630 #undef Ebp
 631
 632 #endif /* _WIN32 */
 633 #endif /* CONFIG_TCC_BACKTRACE */
 634 /* ------------------------------------------------------------- */
 635
 636 #ifdef CONFIG_TCC_STATIC
 637
 638 #define RTLD_LAZY       0x001
 639 #define RTLD_NOW        0x002
 640 #define RTLD_GLOBAL     0x100
 641 #define RTLD_DEFAULT    NULL
 642
 643 /* dummy function for profiling */
 644 void *dlopen(const char *filename, int flag)
 645 {
 646     return NULL;
 647 }
 648
 649 void dlclose(void *p)
 650 {
 651 }
 652 /*
 653 const char *dlerror(void)
 654 {
 655     return "error";
 656 }
 657 */
 658 typedef struct TCCSyms {
 659     char *str;
 660     void *ptr;
 661 } TCCSyms;
 662
 663 #define TCCSYM(a) { #a, &a, },
 664
 665 /* add the symbol you want here if no dynamic linking is done */
 666 static TCCSyms tcc_syms[] = {
 667 #if !defined(CONFIG_TCCBOOT)
 668     TCCSYM(printf)
 669     TCCSYM(fprintf)
 670     TCCSYM(fopen)
 671     TCCSYM(fclose)
 672 #endif
 673     { NULL, NULL },
 674 };
 675
 676 void *resolve_sym(TCCState *s1, const char *symbol)
 677 {
 678     TCCSyms *p;
 679     p = tcc_syms;
 680     while (p->str != NULL) {
 681         if (!strcmp(p->str, symbol))
 682             return p->ptr;
 683         p++;
 684     }
 685     return NULL;
 686 }
 687
 688 #elif !defined(_WIN32)
 689
 690 void *resolve_sym(TCCState *s1, const char *sym)
 691 {
 692     return dlsym(RTLD_DEFAULT, sym);
 693 }
 694
 695 #endif /* CONFIG_TCC_STATIC */
 696
 697 /* ------------------------------------------------------------- */