2 * ELF file handling for TCC
4 * Copyright (c) 2001-2004 Fabrice Bellard
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.
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.
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
23 /* XXX: avoid static variable */
24 static int new_undef_sym
= 0; /* Is there a new undefined sym since last new_undef_sym() */
26 ST_FUNC
int put_elf_str(Section
*s
, const char *sym
)
31 len
= strlen(sym
) + 1;
32 offset
= s
->data_offset
;
33 ptr
= section_ptr_add(s
, len
);
34 memcpy(ptr
, sym
, len
);
38 /* elf symbol hashing function */
39 static unsigned long elf_hash(const unsigned char *name
)
41 unsigned long h
= 0, g
;
44 h
= (h
<< 4) + *name
++;
53 /* rebuild hash table of section s */
54 /* NOTE: we do factorize the hash table code to go faster */
55 static void rebuild_hash(Section
*s
, unsigned int nb_buckets
)
58 int *ptr
, *hash
, nb_syms
, sym_index
, h
;
59 unsigned char *strtab
;
61 strtab
= s
->link
->data
;
62 nb_syms
= s
->data_offset
/ sizeof(ElfW(Sym
));
64 s
->hash
->data_offset
= 0;
65 ptr
= section_ptr_add(s
->hash
, (2 + nb_buckets
+ nb_syms
) * sizeof(int));
70 memset(hash
, 0, (nb_buckets
+ 1) * sizeof(int));
71 ptr
+= nb_buckets
+ 1;
73 sym
= (ElfW(Sym
) *)s
->data
+ 1;
74 for(sym_index
= 1; sym_index
< nb_syms
; sym_index
++) {
75 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
76 h
= elf_hash(strtab
+ sym
->st_name
) % nb_buckets
;
87 /* return the symbol number */
88 ST_FUNC
int put_elf_sym(Section
*s
, addr_t value
, unsigned long size
,
89 int info
, int other
, int shndx
, const char *name
)
91 int name_offset
, sym_index
;
96 sym
= section_ptr_add(s
, sizeof(ElfW(Sym
)));
98 name_offset
= put_elf_str(s
->link
, name
);
101 /* XXX: endianness */
102 sym
->st_name
= name_offset
;
103 sym
->st_value
= value
;
106 sym
->st_other
= other
;
107 sym
->st_shndx
= shndx
;
108 sym_index
= sym
- (ElfW(Sym
) *)s
->data
;
112 ptr
= section_ptr_add(hs
, sizeof(int));
113 base
= (int *)hs
->data
;
114 /* only add global or weak symbols */
115 if (ELFW(ST_BIND
)(info
) != STB_LOCAL
) {
116 /* add another hashing entry */
118 h
= elf_hash((unsigned char *) name
) % nbuckets
;
120 base
[2 + h
] = sym_index
;
122 /* we resize the hash table */
123 hs
->nb_hashed_syms
++;
124 if (hs
->nb_hashed_syms
> 2 * nbuckets
) {
125 rebuild_hash(s
, 2 * nbuckets
);
135 /* find global ELF symbol 'name' and return its index. Return 0 if not
137 ST_FUNC
int find_elf_sym(Section
*s
, const char *name
)
141 int nbuckets
, sym_index
, h
;
147 nbuckets
= ((int *)hs
->data
)[0];
148 h
= elf_hash((unsigned char *) name
) % nbuckets
;
149 sym_index
= ((int *)hs
->data
)[2 + h
];
150 while (sym_index
!= 0) {
151 sym
= &((ElfW(Sym
) *)s
->data
)[sym_index
];
152 name1
= (char *) s
->link
->data
+ sym
->st_name
;
153 if (!strcmp(name
, name1
))
155 sym_index
= ((int *)hs
->data
)[2 + nbuckets
+ sym_index
];
160 /* return elf symbol value, signal error if 'err' is nonzero */
161 ST_FUNC addr_t
get_elf_sym_addr(TCCState
*s
, const char *name
, int err
)
166 sym_index
= find_elf_sym(s
->symtab
, name
);
167 sym
= &((ElfW(Sym
) *)s
->symtab
->data
)[sym_index
];
168 if (!sym_index
|| sym
->st_shndx
== SHN_UNDEF
) {
170 tcc_error("%s not defined", name
);
173 return sym
->st_value
;
176 /* return elf symbol value */
177 LIBTCCAPI
void *tcc_get_symbol(TCCState
*s
, const char *name
)
179 return (void*)(uintptr_t)get_elf_sym_addr(s
, name
, 0);
182 #if defined TCC_IS_NATIVE || defined TCC_TARGET_PE
183 /* return elf symbol value or error */
184 ST_FUNC
void* tcc_get_symbol_err(TCCState
*s
, const char *name
)
186 return (void*)(uintptr_t)get_elf_sym_addr(s
, name
, 1);
190 /* add an elf symbol : check if it is already defined and patch
191 it. Return symbol index. NOTE that sh_num can be SHN_UNDEF. */
192 ST_FUNC
int add_elf_sym(Section
*s
, addr_t value
, unsigned long size
,
193 int info
, int other
, int sh_num
, const char *name
)
196 int sym_bind
, sym_index
, sym_type
, esym_bind
;
197 unsigned char sym_vis
, esym_vis
, new_vis
;
199 sym_bind
= ELFW(ST_BIND
)(info
);
200 sym_type
= ELFW(ST_TYPE
)(info
);
201 sym_vis
= ELFW(ST_VISIBILITY
)(other
);
203 if (sym_bind
!= STB_LOCAL
) {
204 /* we search global or weak symbols */
205 sym_index
= find_elf_sym(s
, name
);
208 esym
= &((ElfW(Sym
) *)s
->data
)[sym_index
];
209 if (esym
->st_shndx
!= SHN_UNDEF
) {
210 esym_bind
= ELFW(ST_BIND
)(esym
->st_info
);
211 /* propagate the most constraining visibility */
212 /* STV_DEFAULT(0)<STV_PROTECTED(3)<STV_HIDDEN(2)<STV_INTERNAL(1) */
213 esym_vis
= ELFW(ST_VISIBILITY
)(esym
->st_other
);
214 if (esym_vis
== STV_DEFAULT
) {
216 } else if (sym_vis
== STV_DEFAULT
) {
219 new_vis
= (esym_vis
< sym_vis
) ? esym_vis
: sym_vis
;
221 esym
->st_other
= (esym
->st_other
& ~ELFW(ST_VISIBILITY
)(-1))
223 other
= esym
->st_other
; /* in case we have to patch esym */
224 if (sh_num
== SHN_UNDEF
) {
225 /* ignore adding of undefined symbol if the
226 corresponding symbol is already defined */
227 } else if (sym_bind
== STB_GLOBAL
&& esym_bind
== STB_WEAK
) {
228 /* global overrides weak, so patch */
230 } else if (sym_bind
== STB_WEAK
&& esym_bind
== STB_GLOBAL
) {
231 /* weak is ignored if already global */
232 } else if (sym_bind
== STB_WEAK
&& esym_bind
== STB_WEAK
) {
233 /* keep first-found weak definition, ignore subsequents */
234 } else if (sym_vis
== STV_HIDDEN
|| sym_vis
== STV_INTERNAL
) {
235 /* ignore hidden symbols after */
236 } else if (esym
->st_shndx
== SHN_COMMON
237 && (sh_num
< SHN_LORESERVE
|| sh_num
== SHN_COMMON
)) {
238 /* gr: Happens with 'tcc ... -static tcctest.c' on e.g. Ubuntu 6.01
239 No idea if this is the correct solution ... */
241 } else if (s
== tcc_state
->dynsymtab_section
) {
242 /* we accept that two DLL define the same symbol */
245 printf("new_bind=%x new_shndx=%x new_vis=%x old_bind=%x old_shndx=%x old_vis=%x\n",
246 sym_bind
, sh_num
, new_vis
, esym_bind
, esym
->st_shndx
, esym_vis
);
248 tcc_error_noabort("'%s' defined twice", name
);
252 esym
->st_info
= ELFW(ST_INFO
)(sym_bind
, sym_type
);
253 esym
->st_shndx
= sh_num
;
255 esym
->st_value
= value
;
256 esym
->st_size
= size
;
257 esym
->st_other
= other
;
261 sym_index
= put_elf_sym(s
, value
, size
,
262 ELFW(ST_INFO
)(sym_bind
, sym_type
), other
,
269 ST_FUNC
void put_elf_reloc(Section
*symtab
, Section
*s
, unsigned long offset
,
270 int type
, int symbol
)
278 /* if no relocation section, create it */
279 snprintf(buf
, sizeof(buf
), REL_SECTION_FMT
, s
->name
);
280 /* if the symtab is allocated, then we consider the relocation
282 sr
= new_section(tcc_state
, buf
, SHT_RELX
, symtab
->sh_flags
);
283 sr
->sh_entsize
= sizeof(ElfW_Rel
);
285 sr
->sh_info
= s
->sh_num
;
288 rel
= section_ptr_add(sr
, sizeof(ElfW_Rel
));
289 rel
->r_offset
= offset
;
290 rel
->r_info
= ELFW(R_INFO
)(symbol
, type
);
291 #ifdef TCC_TARGET_X86_64
296 /* put stab debug information */
298 ST_FUNC
void put_stabs(const char *str
, int type
, int other
, int desc
,
303 sym
= section_ptr_add(stab_section
, sizeof(Stab_Sym
));
305 sym
->n_strx
= put_elf_str(stabstr_section
, str
);
310 sym
->n_other
= other
;
312 sym
->n_value
= value
;
315 ST_FUNC
void put_stabs_r(const char *str
, int type
, int other
, int desc
,
316 unsigned long value
, Section
*sec
, int sym_index
)
318 put_stabs(str
, type
, other
, desc
, value
);
319 put_elf_reloc(symtab_section
, stab_section
,
320 stab_section
->data_offset
- sizeof(unsigned int),
321 R_DATA_32
, sym_index
);
324 ST_FUNC
void put_stabn(int type
, int other
, int desc
, int value
)
326 put_stabs(NULL
, type
, other
, desc
, value
);
329 ST_FUNC
void put_stabd(int type
, int other
, int desc
)
331 put_stabs(NULL
, type
, other
, desc
, 0);
334 /* Browse each elem of type <type> in section <sec> starting at elem <startoff>
335 using variable <elem> */
336 #define for_each_elem(sec, startoff, elem, type) \
337 for (elem = (type *) sec->data + startoff; \
338 elem < (type *) (sec->data + sec->data_offset); elem++)
340 /* In an ELF file symbol table, the local symbols must appear below
341 the global and weak ones. Since TCC cannot sort it while generating
342 the code, we must do it after. All the relocation tables are also
343 modified to take into account the symbol table sorting */
344 static void sort_syms(TCCState
*s1
, Section
*s
)
346 int *old_to_new_syms
;
354 nb_syms
= s
->data_offset
/ sizeof(ElfW(Sym
));
355 new_syms
= tcc_malloc(nb_syms
* sizeof(ElfW(Sym
)));
356 old_to_new_syms
= tcc_malloc(nb_syms
* sizeof(int));
358 /* first pass for local symbols */
359 p
= (ElfW(Sym
) *)s
->data
;
361 for(i
= 0; i
< nb_syms
; i
++) {
362 if (ELFW(ST_BIND
)(p
->st_info
) == STB_LOCAL
) {
363 old_to_new_syms
[i
] = q
- new_syms
;
368 /* save the number of local symbols in section header */
369 s
->sh_info
= q
- new_syms
;
371 /* then second pass for non local symbols */
372 p
= (ElfW(Sym
) *)s
->data
;
373 for(i
= 0; i
< nb_syms
; i
++) {
374 if (ELFW(ST_BIND
)(p
->st_info
) != STB_LOCAL
) {
375 old_to_new_syms
[i
] = q
- new_syms
;
381 /* we copy the new symbols to the old */
382 memcpy(s
->data
, new_syms
, nb_syms
* sizeof(ElfW(Sym
)));
385 /* now we modify all the relocations */
386 for(i
= 1; i
< s1
->nb_sections
; i
++) {
387 sr
= s1
->sections
[i
];
388 if (sr
->sh_type
== SHT_RELX
&& sr
->link
== s
) {
389 for_each_elem(sr
, 0, rel
, ElfW_Rel
) {
390 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
391 type
= ELFW(R_TYPE
)(rel
->r_info
);
392 sym_index
= old_to_new_syms
[sym_index
];
393 rel
->r_info
= ELFW(R_INFO
)(sym_index
, type
);
398 tcc_free(old_to_new_syms
);
401 /* relocate common symbols in the .bss section */
402 ST_FUNC
void relocate_common_syms(void)
405 unsigned long offset
, align
;
407 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
408 if (sym
->st_shndx
== SHN_COMMON
) {
410 align
= sym
->st_value
;
411 offset
= bss_section
->data_offset
;
412 offset
= (offset
+ align
- 1) & -align
;
413 sym
->st_value
= offset
;
414 sym
->st_shndx
= bss_section
->sh_num
;
415 offset
+= sym
->st_size
;
416 bss_section
->data_offset
= offset
;
421 /* relocate symbol table, resolve undefined symbols if do_resolve is
422 true and output error if undefined symbol. */
423 ST_FUNC
void relocate_syms(TCCState
*s1
, int do_resolve
)
425 ElfW(Sym
) *sym
, *esym
;
426 int sym_bind
, sh_num
, sym_index
;
429 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
430 sh_num
= sym
->st_shndx
;
431 if (sh_num
== SHN_UNDEF
) {
432 name
= (char *) strtab_section
->data
+ sym
->st_name
;
433 /* Use ld.so to resolve symbol for us (for tcc -run) */
435 #if defined TCC_IS_NATIVE && !defined _WIN32
437 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
438 addr
= resolve_sym(s1
, name
);
440 sym
->st_value
= (addr_t
)addr
;
444 } else if (s1
->dynsym
) {
445 /* if dynamic symbol exist, then use it */
446 sym_index
= find_elf_sym(s1
->dynsym
, name
);
448 esym
= &((ElfW(Sym
) *)s1
->dynsym
->data
)[sym_index
];
449 sym
->st_value
= esym
->st_value
;
453 /* XXX: _fp_hw seems to be part of the ABI, so we ignore
455 if (!strcmp(name
, "_fp_hw"))
457 /* only weak symbols are accepted to be undefined. Their
459 sym_bind
= ELFW(ST_BIND
)(sym
->st_info
);
460 if (sym_bind
== STB_WEAK
) {
463 tcc_error_noabort("undefined symbol '%s'", name
);
465 } else if (sh_num
< SHN_LORESERVE
) {
466 /* add section base */
467 sym
->st_value
+= s1
->sections
[sym
->st_shndx
]->sh_addr
;
473 #ifdef TCC_HAS_RUNTIME_PLTGOT
474 #ifdef TCC_TARGET_X86_64
475 #define JMP_TABLE_ENTRY_SIZE 14
476 static addr_t
add_jmp_table(TCCState
*s1
, addr_t val
)
478 char *p
= s1
->runtime_plt_and_got
+ s1
->runtime_plt_and_got_offset
;
479 s1
->runtime_plt_and_got_offset
+= JMP_TABLE_ENTRY_SIZE
;
484 *(addr_t
*)(p
+ 6) = val
;
488 static addr_t
add_got_table(TCCState
*s1
, addr_t val
)
490 addr_t
*p
= (addr_t
*)(s1
->runtime_plt_and_got
+ s1
->runtime_plt_and_got_offset
);
491 s1
->runtime_plt_and_got_offset
+= sizeof(addr_t
);
495 #elif defined TCC_TARGET_ARM
496 #define JMP_TABLE_ENTRY_SIZE 8
497 static addr_t
add_jmp_table(TCCState
*s1
, int val
)
499 uint32_t *p
= (uint32_t *)(s1
->runtime_plt_and_got
+ s1
->runtime_plt_and_got_offset
);
500 s1
->runtime_plt_and_got_offset
+= JMP_TABLE_ENTRY_SIZE
;
501 /* ldr pc, [pc, #-4] */
507 #endif /* def TCC_HAS_RUNTIME_PLTGOT */
509 /* relocate a given section (CPU dependent) by applying the relocations
510 in the associated relocation section */
511 ST_FUNC
void relocate_section(TCCState
*s1
, Section
*s
)
513 Section
*sr
= s
->reloc
;
519 #if defined TCC_TARGET_I386 || defined TCC_TARGET_X86_64
520 ElfW_Rel
*qrel
= (ElfW_Rel
*) sr
->data
; /* ptr to next reloc entry reused */
524 for_each_elem(sr
, 0, rel
, ElfW_Rel
) {
525 ptr
= s
->data
+ rel
->r_offset
;
527 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
528 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
530 #ifdef TCC_TARGET_X86_64
531 val
+= rel
->r_addend
;
533 type
= ELFW(R_TYPE
)(rel
->r_info
);
534 addr
= s
->sh_addr
+ rel
->r_offset
;
538 #if defined(TCC_TARGET_I386)
540 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
541 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
542 qrel
->r_offset
= rel
->r_offset
;
544 qrel
->r_info
= ELFW(R_INFO
)(esym_index
, R_386_32
);
548 qrel
->r_info
= ELFW(R_INFO
)(0, R_386_RELATIVE
);
555 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
557 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
559 qrel
->r_offset
= rel
->r_offset
;
560 qrel
->r_info
= ELFW(R_INFO
)(esym_index
, R_386_PC32
);
565 *(int *)ptr
+= val
- addr
;
568 *(int *)ptr
+= val
- addr
;
575 *(int *)ptr
+= s1
->got
->sh_addr
- addr
;
578 *(int *)ptr
+= val
- s1
->got
->sh_addr
;
581 /* we load the got offset */
582 *(int *)ptr
+= s1
->sym_attrs
[sym_index
].got_offset
;
585 if (s1
->output_format
!= TCC_OUTPUT_FORMAT_BINARY
) {
587 tcc_error("can only produce 16-bit binary files");
589 *(short *)ptr
+= val
;
592 if (s1
->output_format
!= TCC_OUTPUT_FORMAT_BINARY
)
594 *(short *)ptr
+= val
- addr
;
596 #elif defined(TCC_TARGET_ARM)
602 int x
, is_thumb
, is_call
, h
, blx_avail
, is_bl
, th_ko
;
603 x
= (*(int *) ptr
) & 0xffffff;
604 (*(int *)ptr
) &= 0xff000000;
608 blx_avail
= (TCC_ARM_VERSION
>= 5);
610 is_bl
= (*(unsigned *) ptr
) >> 24 == 0xeb;
611 is_call
= (type
== R_ARM_CALL
|| (type
== R_ARM_PC24
&& is_bl
));
614 th_ko
= (x
& 3) && (!blx_avail
|| !is_call
);
615 #ifdef TCC_HAS_RUNTIME_PLTGOT
616 if (s1
->output_type
== TCC_OUTPUT_MEMORY
) {
617 if (th_ko
|| x
>= 0x2000000 || x
< -0x2000000) {
618 x
+= add_jmp_table(s1
, val
) - val
; /* add veneer */
619 th_ko
= (x
& 3) && (!blx_avail
|| !is_call
);
620 is_thumb
= 0; /* Veneer uses ARM instructions */
624 if (th_ko
|| x
>= 0x2000000 || x
< -0x2000000)
625 tcc_error("can't relocate value at %x",addr
);
628 /* Only reached if blx is avail and it is a call */
631 (*(int *)ptr
) = 0xfa << 24; /* bl -> blx */
636 /* Since these relocations only concern Thumb-2 and blx instruction was
637 introduced before Thumb-2, we can assume blx is available and not
640 case R_ARM_THM_JUMP24
:
642 int x
, hi
, lo
, s
, j1
, j2
, i1
, i2
, imm10
, imm11
;
643 int to_thumb
, is_call
, to_plt
, blx_bit
= 1 << 12;
647 if (sym
->st_shndx
== SHN_UNDEF
&&
648 ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
)
651 /* Get initial offset */
652 hi
= (*(uint16_t *)ptr
);
653 lo
= (*(uint16_t *)(ptr
+2));
661 x
= (s
<< 24) | (i1
<< 23) | (i2
<< 22) |
662 (imm10
<< 12) | (imm11
<< 1);
666 /* Relocation infos */
669 to_plt
= (val
>= plt
->sh_addr
) &&
670 (val
< plt
->sh_addr
+ plt
->data_offset
);
671 is_call
= (type
== R_ARM_THM_PC22
);
673 /* Compute final offset */
674 if (to_plt
&& !is_call
) /* Point to 1st instr of Thumb stub */
677 if (!to_thumb
&& is_call
) {
678 blx_bit
= 0; /* bl -> blx */
679 x
= (x
+ 3) & -4; /* Compute offset from aligned PC */
682 /* Check that relocation is possible
683 * offset must not be out of range
684 * if target is to be entered in arm mode:
686 - instruction must be a call (bl) or a jump to PLT */
687 if (!to_thumb
|| x
>= 0x1000000 || x
< -0x1000000)
688 if (to_thumb
|| (val
& 2) || (!is_call
&& !to_plt
))
689 tcc_error("can't relocate value at %x",addr
);
691 /* Compute and store final offset */
697 imm10
= (x
>> 12) & 0x3ff;
698 imm11
= (x
>> 1) & 0x7ff;
699 (*(uint16_t *)ptr
) = (uint16_t) ((hi
& 0xf800) |
701 (*(uint16_t *)(ptr
+2)) = (uint16_t) ((lo
& 0xc000) |
702 (j1
<< 13) | blx_bit
| (j2
<< 11) |
707 case R_ARM_MOVW_ABS_NC
:
710 if (type
== R_ARM_MOVT_ABS
)
713 imm4
= (val
>> 12) & 0xf;
714 x
= (imm4
<< 16) | imm12
;
715 if (type
== R_ARM_THM_MOVT_ABS
)
721 case R_ARM_THM_MOVT_ABS
:
722 case R_ARM_THM_MOVW_ABS_NC
:
724 int x
, i
, imm4
, imm3
, imm8
;
725 if (type
== R_ARM_THM_MOVT_ABS
)
728 imm3
= (val
>> 8) & 0x7;
730 imm4
= (val
>> 12) & 0xf;
731 x
= (imm3
<< 28) | (imm8
<< 16) | (i
<< 10) | imm4
;
732 if (type
== R_ARM_THM_MOVT_ABS
)
741 x
= (*(int *)ptr
) & 0x7fffffff;
742 (*(int *)ptr
) &= 0x80000000;
745 if((x
^(x
>>1))&0x40000000)
746 tcc_error("can't relocate value at %x",addr
);
747 (*(int *)ptr
) |= x
& 0x7fffffff;
753 *(int *)ptr
+= val
- addr
;
756 *(int *)ptr
+= s1
->got
->sh_addr
- addr
;
759 *(int *)ptr
+= val
- s1
->got
->sh_addr
;
762 /* we load the got offset */
763 *(int *)ptr
+= s1
->sym_attrs
[sym_index
].got_offset
;
768 /* trade Thumb support for ARMv4 support */
769 if ((0x0ffffff0 & *(int*)ptr
) == 0x012FFF10)
770 *(int*)ptr
^= 0xE12FFF10 ^ 0xE1A0F000; /* BX Rm -> MOV PC, Rm */
773 /* Nothing to do. Normally used to indicate a dependency
774 on a certain symbol (like for exception handling under EABI). */
777 fprintf(stderr
,"FIXME: handle reloc type %x at %x [%p] to %x\n",
778 type
, (unsigned)addr
, ptr
, (unsigned)val
);
780 #elif defined(TCC_TARGET_C67)
788 /* put the low 16 bits of the absolute address
789 add to what is already there */
791 orig
= ((*(int *)(ptr
)) >> 7) & 0xffff;
792 orig
|= (((*(int *)(ptr
+4)) >> 7) & 0xffff) << 16;
794 /* patch both at once - assumes always in pairs Low - High */
796 *(int *) ptr
= (*(int *) ptr
& (~(0xffff << 7)) ) | (((val
+orig
) & 0xffff) << 7);
797 *(int *)(ptr
+4) = (*(int *)(ptr
+4) & (~(0xffff << 7)) ) | ((((val
+orig
)>>16) & 0xffff) << 7);
803 fprintf(stderr
,"FIXME: handle reloc type %x at %x [%p] to %x\n",
804 type
, (unsigned)addr
, ptr
, (unsigned)val
);
806 #elif defined(TCC_TARGET_X86_64)
808 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
809 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
810 qrel
->r_offset
= rel
->r_offset
;
812 qrel
->r_info
= ELFW(R_INFO
)(esym_index
, R_X86_64_64
);
813 qrel
->r_addend
= rel
->r_addend
;
817 qrel
->r_info
= ELFW(R_INFO
)(0, R_X86_64_RELATIVE
);
818 qrel
->r_addend
= *(long long *)ptr
+ val
;
822 *(long long *)ptr
+= val
;
826 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
827 /* XXX: this logic may depend on TCC's codegen
828 now TCC uses R_X86_64_32 even for a 64bit pointer */
829 qrel
->r_info
= ELFW(R_INFO
)(0, R_X86_64_RELATIVE
);
830 qrel
->r_addend
= *(int *)ptr
+ val
;
837 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
839 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
841 qrel
->r_offset
= rel
->r_offset
;
842 qrel
->r_info
= ELFW(R_INFO
)(esym_index
, R_X86_64_PC32
);
843 qrel
->r_addend
= *(int *)ptr
;
851 /* We've put the PLT slot offset into r_addend when generating
852 it, and that's what we must use as relocation value (adjusted
853 by section offset of course). */
854 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
)
855 val
= s1
->plt
->sh_addr
+ rel
->r_addend
;
861 diff
= (long long)val
- addr
;
862 if (diff
<= -2147483647 || diff
> 2147483647) {
863 #ifdef TCC_HAS_RUNTIME_PLTGOT
864 /* XXX: naive support for over 32bit jump */
865 if (s1
->output_type
== TCC_OUTPUT_MEMORY
) {
866 val
= (add_jmp_table(s1
, val
- rel
->r_addend
) +
871 if (diff
<= -2147483647 || diff
> 2147483647) {
872 tcc_error("internal error: relocation failed");
878 case R_X86_64_GLOB_DAT
:
879 case R_X86_64_JUMP_SLOT
:
880 /* They don't need addend */
881 *(int *)ptr
= val
- rel
->r_addend
;
883 case R_X86_64_GOTPCREL
:
884 #ifdef TCC_HAS_RUNTIME_PLTGOT
885 if (s1
->output_type
== TCC_OUTPUT_MEMORY
) {
886 val
= add_got_table(s1
, val
- rel
->r_addend
) + rel
->r_addend
;
887 *(int *)ptr
+= val
- addr
;
891 *(int *)ptr
+= (s1
->got
->sh_addr
- addr
+
892 s1
->sym_attrs
[sym_index
].got_offset
- 4);
894 case R_X86_64_GOTTPOFF
:
895 *(int *)ptr
+= val
- s1
->got
->sh_addr
;
898 /* we load the got offset */
899 *(int *)ptr
+= s1
->sym_attrs
[sym_index
].got_offset
;
902 #error unsupported processor
906 /* if the relocation is allocated, we change its symbol table */
907 if (sr
->sh_flags
& SHF_ALLOC
)
908 sr
->link
= s1
->dynsym
;
911 /* relocate relocation table in 'sr' */
912 static void relocate_rel(TCCState
*s1
, Section
*sr
)
917 s
= s1
->sections
[sr
->sh_info
];
918 for_each_elem(sr
, 0, rel
, ElfW_Rel
)
919 rel
->r_offset
+= s
->sh_addr
;
922 /* count the number of dynamic relocations so that we can reserve
924 static int prepare_dynamic_rel(TCCState
*s1
, Section
*sr
)
927 int sym_index
, esym_index
, type
, count
;
930 for_each_elem(sr
, 0, rel
, ElfW_Rel
) {
931 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
932 type
= ELFW(R_TYPE
)(rel
->r_info
);
934 #if defined(TCC_TARGET_I386)
936 #elif defined(TCC_TARGET_X86_64)
943 #if defined(TCC_TARGET_I386)
945 #elif defined(TCC_TARGET_X86_64)
948 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
957 /* allocate the section */
958 sr
->sh_flags
|= SHF_ALLOC
;
959 sr
->sh_size
= count
* sizeof(ElfW_Rel
);
964 static struct sym_attr
*alloc_sym_attr(TCCState
*s1
, int index
)
967 struct sym_attr
*tab
;
969 if (index
>= s1
->nb_sym_attrs
) {
970 /* find immediately bigger power of 2 and reallocate array */
974 tab
= tcc_realloc(s1
->sym_attrs
, n
* sizeof(*s1
->sym_attrs
));
976 memset(s1
->sym_attrs
+ s1
->nb_sym_attrs
, 0,
977 (n
- s1
->nb_sym_attrs
) * sizeof(*s1
->sym_attrs
));
978 s1
->nb_sym_attrs
= n
;
980 return &s1
->sym_attrs
[index
];
983 /* XXX: suppress that */
984 static void put32(unsigned char *p
, uint32_t val
)
992 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_ARM) || \
993 defined(TCC_TARGET_X86_64)
994 static uint32_t get32(unsigned char *p
)
996 return p
[0] | (p
[1] << 8) | (p
[2] << 16) | (p
[3] << 24);
1000 static void build_got(TCCState
*s1
)
1004 /* if no got, then create it */
1005 s1
->got
= new_section(s1
, ".got", SHT_PROGBITS
, SHF_ALLOC
| SHF_WRITE
);
1006 s1
->got
->sh_entsize
= 4;
1007 add_elf_sym(symtab_section
, 0, 4, ELFW(ST_INFO
)(STB_GLOBAL
, STT_OBJECT
),
1008 0, s1
->got
->sh_num
, "_GLOBAL_OFFSET_TABLE_");
1009 ptr
= section_ptr_add(s1
->got
, 3 * PTR_SIZE
);
1011 /* keep space for _DYNAMIC pointer, if present */
1013 /* two dummy got entries */
1017 /* keep space for _DYNAMIC pointer, if present */
1020 /* two dummy got entries */
1028 /* put a got or plt entry corresponding to a symbol in symtab_section. 'size'
1029 and 'info' can be modifed if more precise info comes from the DLL.
1030 Returns offset of GOT or PLT slot. */
1031 static unsigned long put_got_entry(TCCState
*s1
,
1032 int reloc_type
, unsigned long size
, int info
,
1035 int index
, need_plt_entry
;
1038 unsigned long offset
;
1040 struct sym_attr
*symattr
;
1045 need_plt_entry
= s1
->dynsym
&&
1046 #ifdef TCC_TARGET_X86_64
1047 (reloc_type
== R_X86_64_JUMP_SLOT
);
1048 #elif defined(TCC_TARGET_I386)
1049 (reloc_type
== R_386_JMP_SLOT
);
1050 #elif defined(TCC_TARGET_ARM)
1051 (reloc_type
== R_ARM_JUMP_SLOT
);
1056 /* If a got/plt entry already exists for that symbol, no need to add one */
1057 if (sym_index
< s1
->nb_sym_attrs
) {
1058 if (need_plt_entry
&& s1
->sym_attrs
[sym_index
].plt_offset
)
1059 return s1
->sym_attrs
[sym_index
].plt_offset
;
1060 else if (!need_plt_entry
&& s1
->sym_attrs
[sym_index
].got_offset
)
1061 return s1
->sym_attrs
[sym_index
].got_offset
;
1064 symattr
= alloc_sym_attr(s1
, sym_index
);
1066 /* Only store the GOT offset if it's not generated for the PLT entry. */
1067 if (!need_plt_entry
)
1068 symattr
->got_offset
= s1
->got
->data_offset
;
1071 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1072 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1073 offset
= sym
->st_value
;
1074 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
1075 if (need_plt_entry
) {
1079 unsigned long relofs
;
1081 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1084 /* if we build a DLL, we add a %ebx offset */
1085 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1091 /* add a PLT entry */
1093 if (plt
->data_offset
== 0) {
1094 /* first plt entry */
1095 p
= section_ptr_add(plt
, 16);
1096 p
[0] = 0xff; /* pushl got + PTR_SIZE */
1097 p
[1] = modrm
+ 0x10;
1098 put32(p
+ 2, PTR_SIZE
);
1099 p
[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
1101 put32(p
+ 8, PTR_SIZE
* 2);
1104 /* The PLT slot refers to the relocation entry it needs
1105 via offset. The reloc entry is created below, so its
1106 offset is the current data_offset. */
1107 relofs
= s1
->got
->reloc
? s1
->got
->reloc
->data_offset
: 0;
1108 symattr
->plt_offset
= plt
->data_offset
;
1109 p
= section_ptr_add(plt
, 16);
1110 p
[0] = 0xff; /* jmp *(got + x) */
1112 put32(p
+ 2, s1
->got
->data_offset
);
1113 p
[6] = 0x68; /* push $xxx */
1114 #ifdef TCC_TARGET_X86_64
1115 /* On x86-64, the relocation is referred to by _index_. */
1116 put32(p
+ 7, relofs
/ sizeof (ElfW_Rel
));
1118 put32(p
+ 7, relofs
);
1120 p
[11] = 0xe9; /* jmp plt_start */
1121 put32(p
+ 12, -(plt
->data_offset
));
1123 /* If this was an UNDEF symbol set the offset in the
1124 dynsymtab to the PLT slot, so that PC32 relocs to it
1126 if (sym
->st_shndx
== SHN_UNDEF
)
1127 offset
= plt
->data_offset
- 16;
1129 #elif defined(TCC_TARGET_ARM)
1130 if (need_plt_entry
) {
1134 /* if we build a DLL, we add a %ebx offset */
1135 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1136 tcc_error("DLLs unimplemented!");
1138 /* add a PLT entry */
1140 if (plt
->data_offset
== 0) {
1141 /* first plt entry */
1142 p
= section_ptr_add(plt
, 16);
1143 put32(p
, 0xe52de004); /* push {lr} */
1144 put32(p
+4, 0xe59fe010); /* ldr lr, [pc, #16] */
1145 put32(p
+8, 0xe08fe00e); /* add lr, pc, lr */
1146 put32(p
+12, 0xe5bef008); /* ldr pc, [lr, #8]! */
1149 symattr
->plt_offset
= plt
->data_offset
;
1150 if (symattr
->plt_thumb_stub
) {
1151 p
= section_ptr_add(plt
, 20);
1152 put32(p
, 0x4778); /* bx pc */
1153 put32(p
+2, 0x46c0); /* nop */
1156 p
= section_ptr_add(plt
, 16);
1157 put32(p
, 0xe59fc004); /* ldr ip, [pc, #4] ; GOT entry offset */
1158 put32(p
+4, 0xe08fc00c); /* add ip, pc, ip ; addr of GOT entry */
1159 put32(p
+8, 0xe59cf000); /* ldr pc, [ip] ; jump to GOT entry */
1160 put32(p
+12, s1
->got
->data_offset
); /* GOT entry off once patched */
1162 /* the symbol is modified so that it will be relocated to
1164 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1165 offset
= plt
->data_offset
- 16;
1167 #elif defined(TCC_TARGET_C67)
1168 tcc_error("C67 got not implemented");
1170 #error unsupported CPU
1172 /* XXX This might generate multiple syms for name. */
1173 index
= put_elf_sym(s1
->dynsym
, offset
,
1174 size
, info
, 0, sym
->st_shndx
, name
);
1175 /* Create the relocation (it's against the GOT for PLT
1177 put_elf_reloc(s1
->dynsym
, s1
->got
,
1178 s1
->got
->data_offset
,
1181 /* Without .dynsym (i.e. static link or memory output) we
1182 still need relocs against the generated got, so as to fill
1183 the entries with the symbol values (determined later). */
1184 put_elf_reloc(symtab_section
, s1
->got
,
1185 s1
->got
->data_offset
,
1186 reloc_type
, sym_index
);
1188 /* And now create the GOT slot itself. */
1189 ptr
= section_ptr_add(s1
->got
, PTR_SIZE
);
1192 return symattr
->plt_offset
;
1194 return symattr
->got_offset
;
1197 /* build GOT and PLT entries */
1198 ST_FUNC
void build_got_entries(TCCState
*s1
)
1203 int i
, type
, reloc_type
, sym_index
;
1205 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1206 s
= s1
->sections
[i
];
1207 if (s
->sh_type
!= SHT_RELX
)
1209 /* no need to handle got relocations */
1210 if (s
->link
!= symtab_section
)
1212 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1213 type
= ELFW(R_TYPE
)(rel
->r_info
);
1215 #if defined(TCC_TARGET_I386)
1222 if (type
== R_386_GOT32
|| type
== R_386_PLT32
) {
1223 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1224 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1225 /* look at the symbol got offset. If none, then add one */
1226 if (type
== R_386_GOT32
)
1227 reloc_type
= R_386_GLOB_DAT
;
1229 reloc_type
= R_386_JMP_SLOT
;
1230 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1234 #elif defined(TCC_TARGET_ARM)
1241 if (type
== R_ARM_GOT32
|| type
== R_ARM_PLT32
) {
1242 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1243 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1244 /* look at the symbol got offset. If none, then add one */
1245 if (type
== R_ARM_GOT32
)
1246 reloc_type
= R_ARM_GLOB_DAT
;
1248 reloc_type
= R_ARM_JUMP_SLOT
;
1249 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1253 case R_ARM_THM_JUMP24
:
1254 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1255 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1256 /* We are relocating a jump from thumb code to arm code */
1257 if (sym
->st_shndx
!= SHN_UNDEF
&& !(sym
->st_value
& 1)) {
1260 char *name
, buf
[1024];
1261 Section
*text_section
;
1263 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1264 text_section
= s1
->sections
[sym
->st_shndx
];
1265 /* Modify reloc to target a thumb stub to switch to ARM */
1266 snprintf(buf
, sizeof(buf
), "%s_from_thumb", name
);
1267 index
= put_elf_sym(symtab_section
,
1268 text_section
->data_offset
+ 1,
1269 sym
->st_size
, sym
->st_info
, 0,
1270 sym
->st_shndx
, buf
);
1271 rel
->r_info
= ELFW(R_INFO
)(index
, type
);
1272 /* Create a thumb stub fonction to switch to ARM mode */
1273 put_elf_reloc(symtab_section
, text_section
,
1274 text_section
->data_offset
+ 4, R_ARM_JUMP24
,
1276 p
= section_ptr_add(text_section
, 8);
1277 put32(p
, 0x4778); /* bx pc */
1278 put32(p
+2, 0x46c0); /* nop */
1279 put32(p
+4, 0xeafffffe); /* b $sym */
1281 #elif defined(TCC_TARGET_C67)
1288 if (type
== R_C60_GOT32
|| type
== R_C60_PLT32
) {
1289 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1290 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1291 /* look at the symbol got offset. If none, then add one */
1292 if (type
== R_C60_GOT32
)
1293 reloc_type
= R_C60_GLOB_DAT
;
1295 reloc_type
= R_C60_JMP_SLOT
;
1296 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1300 #elif defined(TCC_TARGET_X86_64)
1301 case R_X86_64_GOT32
:
1302 case R_X86_64_GOTTPOFF
:
1303 case R_X86_64_GOTPCREL
:
1304 case R_X86_64_PLT32
:
1307 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
||
1308 type
== R_X86_64_PLT32
) {
1310 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1311 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1312 /* look at the symbol got offset. If none, then add one */
1313 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
)
1314 reloc_type
= R_X86_64_GLOB_DAT
;
1316 reloc_type
= R_X86_64_JUMP_SLOT
;
1317 ofs
= put_got_entry(s1
, reloc_type
, sym
->st_size
,
1318 sym
->st_info
, sym_index
);
1319 if (type
== R_X86_64_PLT32
1320 && s1
->output_type
!= TCC_OUTPUT_MEMORY
)
1321 /* We store the place of the generated PLT slot
1323 rel
->r_addend
+= ofs
;
1327 #error unsupported CPU
1336 ST_FUNC Section
*new_symtab(TCCState
*s1
,
1337 const char *symtab_name
, int sh_type
, int sh_flags
,
1338 const char *strtab_name
,
1339 const char *hash_name
, int hash_sh_flags
)
1341 Section
*symtab
, *strtab
, *hash
;
1342 int *ptr
, nb_buckets
;
1344 symtab
= new_section(s1
, symtab_name
, sh_type
, sh_flags
);
1345 symtab
->sh_entsize
= sizeof(ElfW(Sym
));
1346 strtab
= new_section(s1
, strtab_name
, SHT_STRTAB
, sh_flags
);
1347 put_elf_str(strtab
, "");
1348 symtab
->link
= strtab
;
1349 put_elf_sym(symtab
, 0, 0, 0, 0, 0, NULL
);
1353 hash
= new_section(s1
, hash_name
, SHT_HASH
, hash_sh_flags
);
1354 hash
->sh_entsize
= sizeof(int);
1355 symtab
->hash
= hash
;
1356 hash
->link
= symtab
;
1358 ptr
= section_ptr_add(hash
, (2 + nb_buckets
+ 1) * sizeof(int));
1359 ptr
[0] = nb_buckets
;
1361 memset(ptr
+ 2, 0, (nb_buckets
+ 1) * sizeof(int));
1365 /* put dynamic tag */
1366 static void put_dt(Section
*dynamic
, int dt
, addr_t val
)
1369 dyn
= section_ptr_add(dynamic
, sizeof(ElfW(Dyn
)));
1371 dyn
->d_un
.d_val
= val
;
1374 static void add_init_array_defines(TCCState
*s1
, const char *section_name
)
1378 char sym_start
[1024];
1381 snprintf(sym_start
, sizeof(sym_start
), "__%s_start", section_name
+ 1);
1382 snprintf(sym_end
, sizeof(sym_end
), "__%s_end", section_name
+ 1);
1384 s
= find_section(s1
, section_name
);
1389 end_offset
= s
->data_offset
;
1392 add_elf_sym(symtab_section
,
1394 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1395 s
->sh_num
, sym_start
);
1396 add_elf_sym(symtab_section
,
1398 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1399 s
->sh_num
, sym_end
);
1402 ST_FUNC
void tcc_add_bcheck(TCCState
*s1
)
1404 #ifdef CONFIG_TCC_BCHECK
1406 Section
*init_section
;
1407 unsigned char *pinit
;
1410 if (0 == s1
->do_bounds_check
)
1413 /* XXX: add an object file to do that */
1414 ptr
= section_ptr_add(bounds_section
, sizeof(unsigned long));
1416 add_elf_sym(symtab_section
, 0, 0,
1417 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1418 bounds_section
->sh_num
, "__bounds_start");
1419 #ifdef TCC_TARGET_I386
1420 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
) {
1421 /* add 'call __bound_init()' in .init section */
1422 init_section
= find_section(s1
, ".init");
1423 pinit
= section_ptr_add(init_section
, 5);
1425 put32(pinit
+ 1, -4);
1426 sym_index
= find_elf_sym(symtab_section
, "__bound_init");
1427 put_elf_reloc(symtab_section
, init_section
,
1428 init_section
->data_offset
- 4, R_386_PC32
, sym_index
);
1434 static inline int tcc_add_support(TCCState
*s1
, const char *filename
)
1437 snprintf(buf
, sizeof(buf
), "%s/%s", s1
->tcc_lib_path
, filename
);
1438 return tcc_add_file(s1
, buf
);
1441 /* add tcc runtime libraries */
1442 ST_FUNC
void tcc_add_runtime(TCCState
*s1
)
1445 if (!s1
->nostdlib
) {
1446 tcc_add_library(s1
, "c");
1447 #ifdef CONFIG_USE_LIBGCC
1448 if (!s1
->static_link
) {
1449 tcc_add_file(s1
, TCC_LIBGCC
);
1450 tcc_add_support(s1
, "libtcc1.a");
1452 tcc_add_support(s1
, "libtcc1.a");
1454 tcc_add_support(s1
, "libtcc1.a");
1458 /* tcc_add_bcheck tries to relocate a call to __bound_init in _init so
1459 libtcc1.a must be loaded before for __bound_init to be defined and
1460 crtn.o must be loaded after to not finalize _init too early. */
1463 if (!s1
->nostdlib
) {
1464 /* add crt end if not memory output */
1465 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
)
1466 tcc_add_crt(s1
, "crtn.o");
1470 /* add various standard linker symbols (must be done after the
1471 sections are filled (for example after allocating common
1473 ST_FUNC
void tcc_add_linker_symbols(TCCState
*s1
)
1479 add_elf_sym(symtab_section
,
1480 text_section
->data_offset
, 0,
1481 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1482 text_section
->sh_num
, "_etext");
1483 add_elf_sym(symtab_section
,
1484 data_section
->data_offset
, 0,
1485 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1486 data_section
->sh_num
, "_edata");
1487 add_elf_sym(symtab_section
,
1488 bss_section
->data_offset
, 0,
1489 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1490 bss_section
->sh_num
, "_end");
1491 /* horrible new standard ldscript defines */
1492 add_init_array_defines(s1
, ".preinit_array");
1493 add_init_array_defines(s1
, ".init_array");
1494 add_init_array_defines(s1
, ".fini_array");
1496 /* add start and stop symbols for sections whose name can be
1498 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1499 s
= s1
->sections
[i
];
1500 if (s
->sh_type
== SHT_PROGBITS
&&
1501 (s
->sh_flags
& SHF_ALLOC
)) {
1505 /* check if section name can be expressed in C */
1511 if (!isid(ch
) && !isnum(ch
))
1515 snprintf(buf
, sizeof(buf
), "__start_%s", s
->name
);
1516 add_elf_sym(symtab_section
,
1518 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1520 snprintf(buf
, sizeof(buf
), "__stop_%s", s
->name
);
1521 add_elf_sym(symtab_section
,
1523 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1530 static void tcc_output_binary(TCCState
*s1
, FILE *f
,
1531 const int *sec_order
)
1534 int i
, offset
, size
;
1537 for(i
=1;i
<s1
->nb_sections
;i
++) {
1538 s
= s1
->sections
[sec_order
[i
]];
1539 if (s
->sh_type
!= SHT_NOBITS
&&
1540 (s
->sh_flags
& SHF_ALLOC
)) {
1541 while (offset
< s
->sh_offset
) {
1546 fwrite(s
->data
, 1, size
, f
);
1552 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1554 #define EXTRA_RELITEMS 14
1556 /* move the relocation value from .dynsym to .got */
1557 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1559 uint32_t *gotd
= (void *)s1
->got
->data
;
1562 gotd
+= 3; /* dummy entries in .got */
1563 /* relocate symbols in .dynsym */
1564 for_each_elem(s
, 1, sym
, ElfW(Sym
)) {
1565 if (sym
->st_shndx
== SHN_UNDEF
) {
1566 *gotd
++ = sym
->st_value
+ 6; /* XXX 6 is magic ? */
1573 #define EXTRA_RELITEMS 9
1575 /* zero plt offsets of weak symbols in .dynsym */
1576 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1580 for_each_elem(s
, 1, sym
, ElfW(Sym
))
1581 if (sym
->st_shndx
== SHN_UNDEF
&& ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
)
1586 ST_FUNC
void fill_got_entry(TCCState
*s1
, ElfW_Rel
*rel
)
1588 int sym_index
= ELFW(R_SYM
) (rel
->r_info
);
1589 ElfW(Sym
) *sym
= &((ElfW(Sym
) *) symtab_section
->data
)[sym_index
];
1590 unsigned long offset
;
1592 if (sym_index
>= s1
->nb_sym_attrs
)
1594 offset
= s1
->sym_attrs
[sym_index
].got_offset
;
1595 section_reserve(s1
->got
, offset
+ PTR_SIZE
);
1596 #ifdef TCC_TARGET_X86_64
1597 /* only works for x86-64 */
1598 put32(s1
->got
->data
+ offset
+ 4, sym
->st_value
>> 32);
1600 put32(s1
->got
->data
+ offset
, sym
->st_value
& 0xffffffff);
1603 /* Perform relocation to GOT or PLTÂ entries */
1604 ST_FUNC
void fill_got(TCCState
*s1
)
1610 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1611 s
= s1
->sections
[i
];
1612 if (s
->sh_type
!= SHT_RELX
)
1614 /* no need to handle got relocations */
1615 if (s
->link
!= symtab_section
)
1617 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1618 switch (ELFW(R_TYPE
) (rel
->r_info
)) {
1619 case R_X86_64_GOT32
:
1620 case R_X86_64_GOTPCREL
:
1621 case R_X86_64_PLT32
:
1622 fill_got_entry(s1
, rel
);
1629 /* Bind symbols of executable: resolve undefined symbols from exported symbols
1630 in shared libraries and export non local defined symbols to shared libraries
1631 if -rdynamic switch was given on command line */
1632 static void bind_exe_dynsyms(TCCState
*s1
)
1635 int sym_index
, index
;
1636 ElfW(Sym
) *sym
, *esym
;
1639 /* Resolve undefined symbols from dynamic symbols. When there is a match:
1640 - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
1641 - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
1642 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1643 if (sym
->st_shndx
== SHN_UNDEF
) {
1644 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1645 sym_index
= find_elf_sym(s1
->dynsymtab_section
, name
);
1647 esym
= &((ElfW(Sym
) *)s1
->dynsymtab_section
->data
)[sym_index
];
1648 type
= ELFW(ST_TYPE
)(esym
->st_info
);
1649 if ((type
== STT_FUNC
) || (type
== STT_GNU_IFUNC
)) {
1650 /* Indirect functions shall have STT_FUNC type in executable
1651 * dynsym section. Indeed, a dlsym call following a lazy
1652 * resolution would pick the symbol value from the
1653 * executable dynsym entry which would contain the address
1654 * of the function wanted by the caller of dlsym instead of
1655 * the address of the function that would return that
1657 put_got_entry(s1
, R_JMP_SLOT
, esym
->st_size
,
1658 ELFW(ST_INFO
)(STB_GLOBAL
,STT_FUNC
),
1659 sym
- (ElfW(Sym
) *)symtab_section
->data
);
1660 } else if (type
== STT_OBJECT
) {
1661 unsigned long offset
;
1663 offset
= bss_section
->data_offset
;
1664 /* XXX: which alignment ? */
1665 offset
= (offset
+ 16 - 1) & -16;
1666 index
= put_elf_sym(s1
->dynsym
, offset
, esym
->st_size
,
1667 esym
->st_info
, 0, bss_section
->sh_num
,
1669 /* Ensure R_COPY works for weak symbol aliases */
1670 if (ELFW(ST_BIND
)(esym
->st_info
) == STB_WEAK
) {
1671 for_each_elem(s1
->dynsymtab_section
, 1, dynsym
, ElfW(Sym
)) {
1672 if ((dynsym
->st_value
== esym
->st_value
)
1673 && (ELFW(ST_BIND
)(dynsym
->st_info
) == STB_GLOBAL
)) {
1674 char *dynname
= (char *) s1
->dynsymtab_section
->link
->data
1676 put_elf_sym(s1
->dynsym
, offset
, dynsym
->st_size
,
1678 bss_section
->sh_num
, dynname
);
1683 put_elf_reloc(s1
->dynsym
, bss_section
,
1684 offset
, R_COPY
, index
);
1685 offset
+= esym
->st_size
;
1686 bss_section
->data_offset
= offset
;
1689 /* STB_WEAK undefined symbols are accepted */
1690 /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
1691 if (ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
||
1692 !strcmp(name
, "_fp_hw")) {
1694 tcc_error_noabort("undefined symbol '%s'", name
);
1697 } else if (s1
->rdynamic
&& ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1698 /* if -rdynamic option, then export all non local symbols */
1699 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1700 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
, sym
->st_info
,
1701 0, sym
->st_shndx
, name
);
1706 /* Bind symbols of libraries: export non local symbols of executable that
1707 resolve undefined symbols of shared libraries */
1708 static void bind_libs_dynsyms(TCCState
*s1
)
1712 ElfW(Sym
) *sym
, *esym
;
1714 /* now look at unresolved dynamic symbols and export
1715 corresponding symbol */
1716 for_each_elem(s1
->dynsymtab_section
, 1, esym
, ElfW(Sym
)) {
1717 if (esym
->st_shndx
== SHN_UNDEF
) {
1718 name
= (char *) s1
->dynsymtab_section
->link
->data
+ esym
->st_name
;
1719 sym_index
= find_elf_sym(symtab_section
, name
);
1721 /* XXX: avoid adding a symbol if already present because of
1723 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1724 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1725 sym
->st_info
, 0, sym
->st_shndx
, name
);
1727 /* weak symbols can stay undefined */
1728 if (ELFW(ST_BIND
)(esym
->st_info
) != STB_WEAK
)
1729 tcc_warning("undefined dynamic symbol '%s'", name
);
1735 /* Export all non local symbols (for shared libraries) */
1736 static void export_global_syms(TCCState
*s1
)
1738 int nb_syms
, dynindex
, index
;
1742 nb_syms
= symtab_section
->data_offset
/ sizeof(ElfW(Sym
));
1743 s1
->symtab_to_dynsym
= tcc_mallocz(sizeof(int) * nb_syms
);
1744 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1745 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1746 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1747 dynindex
= put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1748 sym
->st_info
, 0, sym
->st_shndx
, name
);
1749 index
= sym
- (ElfW(Sym
) *) symtab_section
->data
;
1750 s1
->symtab_to_dynsym
[index
] = dynindex
;
1755 /* relocate the PLT: compute addresses and offsets in the PLT now that final
1756 address for PLT and GOT are known (see fill_program_header) */
1757 static void relocate_plt(TCCState
*s1
)
1762 p_end
= p
+ s1
->plt
->data_offset
;
1764 #if defined(TCC_TARGET_I386)
1765 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1766 put32(p
+ 8, get32(p
+ 8) + s1
->got
->sh_addr
);
1769 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1772 #elif defined(TCC_TARGET_X86_64)
1773 int x
= s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 6;
1774 put32(p
+ 2, get32(p
+ 2) + x
);
1775 put32(p
+ 8, get32(p
+ 8) + x
- 6);
1778 put32(p
+ 2, get32(p
+ 2) + x
+ s1
->plt
->data
- p
);
1781 #elif defined(TCC_TARGET_ARM)
1783 x
=s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 12;
1786 if (get32(p
) == 0x46c04778) /* PLT Thumb stub present */
1788 put32(p
+ 12, x
+ get32(p
+ 12) + s1
->plt
->data
- p
);
1791 #elif defined(TCC_TARGET_C67)
1794 #error unsupported CPU
1799 /* Allocate strings for section names and decide if an unallocated section
1802 NOTE: the strsec section comes last, so its size is also correct ! */
1803 static void alloc_sec_names(TCCState
*s1
, int file_type
, Section
*strsec
)
1808 /* Allocate strings for section names */
1809 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1810 s
= s1
->sections
[i
];
1811 s
->sh_name
= put_elf_str(strsec
, s
->name
);
1812 /* when generating a DLL, we include relocations but we may
1814 if (file_type
== TCC_OUTPUT_DLL
&&
1815 s
->sh_type
== SHT_RELX
&&
1816 !(s
->sh_flags
& SHF_ALLOC
)) {
1817 /* gr: avoid bogus relocs for empty (debug) sections */
1818 if (s1
->sections
[s
->sh_info
]->sh_flags
& SHF_ALLOC
)
1819 prepare_dynamic_rel(s1
, s
);
1820 else if (s1
->do_debug
)
1821 s
->sh_size
= s
->data_offset
;
1822 } else if (s1
->do_debug
||
1823 file_type
== TCC_OUTPUT_OBJ
||
1824 (s
->sh_flags
& SHF_ALLOC
) ||
1825 i
== (s1
->nb_sections
- 1)) {
1826 /* we output all sections if debug or object file */
1827 s
->sh_size
= s
->data_offset
;
1832 /* Info to be copied in dynamic section */
1836 unsigned long dyn_rel_off
;
1839 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1845 /* Assign sections to segments and decide how are sections laid out when loaded
1846 in memory. This function also fills corresponding program headers. */
1847 static int layout_sections(TCCState
*s1
, ElfW(Phdr
) *phdr
, int phnum
,
1848 Section
*interp
, struct dyn_inf
*dyninf
,
1851 int i
, j
, k
, file_type
, sh_order_index
, file_offset
;
1857 file_type
= s1
->output_type
;
1859 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
1860 file_offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
1865 if (s1
->has_text_addr
) {
1866 int a_offset
, p_offset
;
1867 addr
= s1
->text_addr
;
1868 /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
1870 a_offset
= (int) (addr
& (s1
->section_align
- 1));
1871 p_offset
= file_offset
& (s1
->section_align
- 1);
1872 if (a_offset
< p_offset
)
1873 a_offset
+= s1
->section_align
;
1874 file_offset
+= (a_offset
- p_offset
);
1876 if (file_type
== TCC_OUTPUT_DLL
)
1879 addr
= ELF_START_ADDR
;
1880 /* compute address after headers */
1881 addr
+= (file_offset
& (s1
->section_align
- 1));
1885 /* Leave one program headers for the program interpreter and one for
1886 the program header table itself if needed. These are done later as
1887 they require section layout to be done first. */
1889 ph
+= 1 + HAVE_PHDR
;
1891 /* dynamic relocation table information, for .dynamic section */
1892 dyninf
->rel_addr
= dyninf
->rel_size
= 0;
1893 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1894 dyninf
->bss_addr
= dyninf
->bss_size
= 0;
1897 for(j
= 0; j
< 2; j
++) {
1898 ph
->p_type
= PT_LOAD
;
1900 ph
->p_flags
= PF_R
| PF_X
;
1902 ph
->p_flags
= PF_R
| PF_W
;
1903 ph
->p_align
= s1
->section_align
;
1905 /* Decide the layout of sections loaded in memory. This must
1906 be done before program headers are filled since they contain
1907 info about the layout. We do the following ordering: interp,
1908 symbol tables, relocations, progbits, nobits */
1909 /* XXX: do faster and simpler sorting */
1910 for(k
= 0; k
< 5; k
++) {
1911 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1912 s
= s1
->sections
[i
];
1913 /* compute if section should be included */
1915 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1919 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1920 (SHF_ALLOC
| SHF_WRITE
))
1926 } else if (s
->sh_type
== SHT_DYNSYM
||
1927 s
->sh_type
== SHT_STRTAB
||
1928 s
->sh_type
== SHT_HASH
) {
1931 } else if (s
->sh_type
== SHT_RELX
) {
1934 } else if (s
->sh_type
== SHT_NOBITS
) {
1941 sec_order
[sh_order_index
++] = i
;
1943 /* section matches: we align it and add its size */
1945 addr
= (addr
+ s
->sh_addralign
- 1) &
1946 ~(s
->sh_addralign
- 1);
1947 file_offset
+= (int) ( addr
- tmp
);
1948 s
->sh_offset
= file_offset
;
1951 /* update program header infos */
1952 if (ph
->p_offset
== 0) {
1953 ph
->p_offset
= file_offset
;
1955 ph
->p_paddr
= ph
->p_vaddr
;
1957 /* update dynamic relocation infos */
1958 if (s
->sh_type
== SHT_RELX
) {
1959 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1960 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.got")) {
1961 dyninf
->rel_addr
= addr
;
1962 dyninf
->rel_size
+= s
->sh_size
; /* XXX only first rel. */
1964 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.bss")) {
1965 dyninf
->bss_addr
= addr
;
1966 dyninf
->bss_size
= s
->sh_size
; /* XXX only first rel. */
1969 if (dyninf
->rel_size
== 0)
1970 dyninf
->rel_addr
= addr
;
1971 dyninf
->rel_size
+= s
->sh_size
;
1975 if (s
->sh_type
!= SHT_NOBITS
)
1976 file_offset
+= s
->sh_size
;
1980 /* Make the first PT_LOAD segment include the program
1981 headers itself (and the ELF header as well), it'll
1982 come out with same memory use but will make various
1983 tools like binutils strip work better. */
1984 ph
->p_offset
&= ~(ph
->p_align
- 1);
1985 ph
->p_vaddr
&= ~(ph
->p_align
- 1);
1986 ph
->p_paddr
&= ~(ph
->p_align
- 1);
1988 ph
->p_filesz
= file_offset
- ph
->p_offset
;
1989 ph
->p_memsz
= addr
- ph
->p_vaddr
;
1992 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
) {
1993 /* if in the middle of a page, we duplicate the page in
1994 memory so that one copy is RX and the other is RW */
1995 if ((addr
& (s1
->section_align
- 1)) != 0)
1996 addr
+= s1
->section_align
;
1998 addr
= (addr
+ s1
->section_align
- 1) & ~(s1
->section_align
- 1);
1999 file_offset
= (file_offset
+ s1
->section_align
- 1) &
2000 ~(s1
->section_align
- 1);
2006 /* all other sections come after */
2007 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2008 s
= s1
->sections
[i
];
2009 if (phnum
> 0 && (s
->sh_flags
& SHF_ALLOC
))
2011 sec_order
[sh_order_index
++] = i
;
2013 file_offset
= (file_offset
+ s
->sh_addralign
- 1) &
2014 ~(s
->sh_addralign
- 1);
2015 s
->sh_offset
= file_offset
;
2016 if (s
->sh_type
!= SHT_NOBITS
)
2017 file_offset
+= s
->sh_size
;
2023 static void fill_unloadable_phdr(ElfW(Phdr
) *phdr
, int phnum
, Section
*interp
,
2028 /* if interpreter, then add corresponding program header */
2034 int len
= phnum
* sizeof(ElfW(Phdr
));
2036 ph
->p_type
= PT_PHDR
;
2037 ph
->p_offset
= sizeof(ElfW(Ehdr
));
2038 ph
->p_vaddr
= interp
->sh_addr
- len
;
2039 ph
->p_paddr
= ph
->p_vaddr
;
2040 ph
->p_filesz
= ph
->p_memsz
= len
;
2041 ph
->p_flags
= PF_R
| PF_X
;
2042 ph
->p_align
= 4; /* interp->sh_addralign; */
2046 ph
->p_type
= PT_INTERP
;
2047 ph
->p_offset
= interp
->sh_offset
;
2048 ph
->p_vaddr
= interp
->sh_addr
;
2049 ph
->p_paddr
= ph
->p_vaddr
;
2050 ph
->p_filesz
= interp
->sh_size
;
2051 ph
->p_memsz
= interp
->sh_size
;
2053 ph
->p_align
= interp
->sh_addralign
;
2056 /* if dynamic section, then add corresponding program header */
2058 ph
= &phdr
[phnum
- 1];
2060 ph
->p_type
= PT_DYNAMIC
;
2061 ph
->p_offset
= dynamic
->sh_offset
;
2062 ph
->p_vaddr
= dynamic
->sh_addr
;
2063 ph
->p_paddr
= ph
->p_vaddr
;
2064 ph
->p_filesz
= dynamic
->sh_size
;
2065 ph
->p_memsz
= dynamic
->sh_size
;
2066 ph
->p_flags
= PF_R
| PF_W
;
2067 ph
->p_align
= dynamic
->sh_addralign
;
2071 /* Fill the dynamic section with tags describing the address and size of
2073 static void fill_dynamic(TCCState
*s1
, struct dyn_inf
*dyninf
)
2077 dynamic
= dyninf
->dynamic
;
2079 /* put dynamic section entries */
2080 dynamic
->data_offset
= dyninf
->dyn_rel_off
;
2081 put_dt(dynamic
, DT_HASH
, s1
->dynsym
->hash
->sh_addr
);
2082 put_dt(dynamic
, DT_STRTAB
, dyninf
->dynstr
->sh_addr
);
2083 put_dt(dynamic
, DT_SYMTAB
, s1
->dynsym
->sh_addr
);
2084 put_dt(dynamic
, DT_STRSZ
, dyninf
->dynstr
->data_offset
);
2085 put_dt(dynamic
, DT_SYMENT
, sizeof(ElfW(Sym
)));
2086 #ifdef TCC_TARGET_X86_64
2087 put_dt(dynamic
, DT_RELA
, dyninf
->rel_addr
);
2088 put_dt(dynamic
, DT_RELASZ
, dyninf
->rel_size
);
2089 put_dt(dynamic
, DT_RELAENT
, sizeof(ElfW_Rel
));
2091 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2092 put_dt(dynamic
, DT_PLTGOT
, s1
->got
->sh_addr
);
2093 put_dt(dynamic
, DT_PLTRELSZ
, dyninf
->rel_size
);
2094 put_dt(dynamic
, DT_JMPREL
, dyninf
->rel_addr
);
2095 put_dt(dynamic
, DT_PLTREL
, DT_REL
);
2096 put_dt(dynamic
, DT_REL
, dyninf
->bss_addr
);
2097 put_dt(dynamic
, DT_RELSZ
, dyninf
->bss_size
);
2099 put_dt(dynamic
, DT_REL
, dyninf
->rel_addr
);
2100 put_dt(dynamic
, DT_RELSZ
, dyninf
->rel_size
);
2101 put_dt(dynamic
, DT_RELENT
, sizeof(ElfW_Rel
));
2105 put_dt(dynamic
, DT_DEBUG
, 0);
2106 put_dt(dynamic
, DT_NULL
, 0);
2109 /* Relocate remaining sections and symbols (that is those not related to
2111 static int final_sections_reloc(TCCState
*s1
)
2116 relocate_syms(s1
, 0);
2118 if (s1
->nb_errors
!= 0)
2121 /* relocate sections */
2122 /* XXX: ignore sections with allocated relocations ? */
2123 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2124 s
= s1
->sections
[i
];
2125 if (s
->reloc
&& s
!= s1
->got
)
2126 relocate_section(s1
, s
);
2129 /* relocate relocation entries if the relocation tables are
2130 allocated in the executable */
2131 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2132 s
= s1
->sections
[i
];
2133 if ((s
->sh_flags
& SHF_ALLOC
) &&
2134 s
->sh_type
== SHT_RELX
) {
2135 relocate_rel(s1
, s
);
2141 /* Create an ELF file on disk.
2142 This function handle ELF specific layout requirements */
2143 static void tcc_output_elf(TCCState
*s1
, FILE *f
, int phnum
, ElfW(Phdr
) *phdr
,
2144 int file_offset
, int *sec_order
)
2146 int i
, shnum
, offset
, size
, file_type
;
2149 ElfW(Shdr
) shdr
, *sh
;
2151 file_type
= s1
->output_type
;
2152 shnum
= s1
->nb_sections
;
2154 memset(&ehdr
, 0, sizeof(ehdr
));
2157 ehdr
.e_phentsize
= sizeof(ElfW(Phdr
));
2158 ehdr
.e_phnum
= phnum
;
2159 ehdr
.e_phoff
= sizeof(ElfW(Ehdr
));
2163 file_offset
= (file_offset
+ 3) & -4;
2166 ehdr
.e_ident
[0] = ELFMAG0
;
2167 ehdr
.e_ident
[1] = ELFMAG1
;
2168 ehdr
.e_ident
[2] = ELFMAG2
;
2169 ehdr
.e_ident
[3] = ELFMAG3
;
2170 ehdr
.e_ident
[4] = ELFCLASSW
;
2171 ehdr
.e_ident
[5] = ELFDATA2LSB
;
2172 ehdr
.e_ident
[6] = EV_CURRENT
;
2173 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2174 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_FREEBSD
;
2176 #ifdef TCC_TARGET_ARM
2178 ehdr
.e_ident
[EI_OSABI
] = 0;
2179 ehdr
.e_flags
= EF_ARM_EABI_VER4
;
2180 if (file_type
== TCC_OUTPUT_EXE
|| file_type
== TCC_OUTPUT_DLL
)
2181 ehdr
.e_flags
|= EF_ARM_HASENTRY
;
2182 if (s1
->float_abi
== ARM_HARD_FLOAT
)
2183 ehdr
.e_flags
|= EF_ARM_VFP_FLOAT
;
2185 ehdr
.e_flags
|= EF_ARM_SOFT_FLOAT
;
2187 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_ARM
;
2192 case TCC_OUTPUT_EXE
:
2193 ehdr
.e_type
= ET_EXEC
;
2194 ehdr
.e_entry
= get_elf_sym_addr(s1
, "_start", 1);
2196 case TCC_OUTPUT_DLL
:
2197 ehdr
.e_type
= ET_DYN
;
2198 ehdr
.e_entry
= text_section
->sh_addr
; /* XXX: is it correct ? */
2200 case TCC_OUTPUT_OBJ
:
2201 ehdr
.e_type
= ET_REL
;
2204 ehdr
.e_machine
= EM_TCC_TARGET
;
2205 ehdr
.e_version
= EV_CURRENT
;
2206 ehdr
.e_shoff
= file_offset
;
2207 ehdr
.e_ehsize
= sizeof(ElfW(Ehdr
));
2208 ehdr
.e_shentsize
= sizeof(ElfW(Shdr
));
2209 ehdr
.e_shnum
= shnum
;
2210 ehdr
.e_shstrndx
= shnum
- 1;
2212 fwrite(&ehdr
, 1, sizeof(ElfW(Ehdr
)), f
);
2213 fwrite(phdr
, 1, phnum
* sizeof(ElfW(Phdr
)), f
);
2214 offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
2216 sort_syms(s1
, symtab_section
);
2217 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2218 s
= s1
->sections
[sec_order
[i
]];
2219 if (s
->sh_type
!= SHT_NOBITS
) {
2220 if (s
->sh_type
== SHT_DYNSYM
)
2221 patch_dynsym_undef(s1
, s
);
2222 while (offset
< s
->sh_offset
) {
2227 fwrite(s
->data
, 1, size
, f
);
2232 /* output section headers */
2233 while (offset
< ehdr
.e_shoff
) {
2238 for(i
= 0; i
< s1
->nb_sections
; i
++) {
2240 memset(sh
, 0, sizeof(ElfW(Shdr
)));
2241 s
= s1
->sections
[i
];
2243 sh
->sh_name
= s
->sh_name
;
2244 sh
->sh_type
= s
->sh_type
;
2245 sh
->sh_flags
= s
->sh_flags
;
2246 sh
->sh_entsize
= s
->sh_entsize
;
2247 sh
->sh_info
= s
->sh_info
;
2249 sh
->sh_link
= s
->link
->sh_num
;
2250 sh
->sh_addralign
= s
->sh_addralign
;
2251 sh
->sh_addr
= s
->sh_addr
;
2252 sh
->sh_offset
= s
->sh_offset
;
2253 sh
->sh_size
= s
->sh_size
;
2255 fwrite(sh
, 1, sizeof(ElfW(Shdr
)), f
);
2259 /* Write an elf, coff or "binary" file */
2260 static int tcc_write_elf_file(TCCState
*s1
, const char *filename
, int phnum
,
2261 ElfW(Phdr
) *phdr
, int file_offset
, int *sec_order
)
2263 int fd
, mode
, file_type
;
2266 file_type
= s1
->output_type
;
2267 if (file_type
== TCC_OUTPUT_OBJ
)
2272 fd
= open(filename
, O_WRONLY
| O_CREAT
| O_TRUNC
| O_BINARY
, mode
);
2274 tcc_error_noabort("could not write '%s'", filename
);
2277 f
= fdopen(fd
, "wb");
2279 printf("<- %s\n", filename
);
2281 #ifdef TCC_TARGET_COFF
2282 if (s1
->output_format
== TCC_OUTPUT_FORMAT_COFF
)
2283 tcc_output_coff(s1
, f
);
2286 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
2287 tcc_output_elf(s1
, f
, phnum
, phdr
, file_offset
, sec_order
);
2289 tcc_output_binary(s1
, f
, sec_order
);
2295 /* Output an elf, coff or binary file */
2296 /* XXX: suppress unneeded sections */
2297 static int elf_output_file(TCCState
*s1
, const char *filename
)
2299 int i
, ret
, phnum
, shnum
, file_type
, file_offset
, *sec_order
;
2300 struct dyn_inf dyninf
;
2303 Section
*strsec
, *interp
, *dynamic
, *dynstr
;
2305 file_type
= s1
->output_type
;
2308 /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
2309 if (file_type
!= TCC_OUTPUT_OBJ
) {
2310 tcc_add_runtime(s1
);
2315 interp
= dynamic
= dynstr
= NULL
; /* avoid warning */
2316 dyninf
.dyn_rel_off
= 0; /* avoid warning */
2318 if (file_type
!= TCC_OUTPUT_OBJ
) {
2319 relocate_common_syms();
2321 tcc_add_linker_symbols(s1
);
2323 if (!s1
->static_link
) {
2324 if (file_type
== TCC_OUTPUT_EXE
) {
2326 /* allow override the dynamic loader */
2327 const char *elfint
= getenv("LD_SO");
2329 elfint
= DEFAULT_ELFINTERP(s1
);
2330 /* add interpreter section only if executable */
2331 interp
= new_section(s1
, ".interp", SHT_PROGBITS
, SHF_ALLOC
);
2332 interp
->sh_addralign
= 1;
2333 ptr
= section_ptr_add(interp
, 1 + strlen(elfint
));
2334 strcpy(ptr
, elfint
);
2337 /* add dynamic symbol table */
2338 s1
->dynsym
= new_symtab(s1
, ".dynsym", SHT_DYNSYM
, SHF_ALLOC
,
2340 ".hash", SHF_ALLOC
);
2341 dynstr
= s1
->dynsym
->link
;
2343 /* add dynamic section */
2344 dynamic
= new_section(s1
, ".dynamic", SHT_DYNAMIC
,
2345 SHF_ALLOC
| SHF_WRITE
);
2346 dynamic
->link
= dynstr
;
2347 dynamic
->sh_entsize
= sizeof(ElfW(Dyn
));
2350 s1
->plt
= new_section(s1
, ".plt", SHT_PROGBITS
,
2351 SHF_ALLOC
| SHF_EXECINSTR
);
2352 s1
->plt
->sh_entsize
= 4;
2356 if (file_type
== TCC_OUTPUT_EXE
) {
2357 bind_exe_dynsyms(s1
);
2359 if (s1
->nb_errors
) {
2364 bind_libs_dynsyms(s1
);
2365 } else /* shared library case: simply export all global symbols */
2366 export_global_syms(s1
);
2368 build_got_entries(s1
);
2370 /* add a list of needed dlls */
2371 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2372 DLLReference
*dllref
= s1
->loaded_dlls
[i
];
2373 if (dllref
->level
== 0)
2374 put_dt(dynamic
, DT_NEEDED
, put_elf_str(dynstr
, dllref
->name
));
2378 put_dt(dynamic
, DT_RPATH
, put_elf_str(dynstr
, s1
->rpath
));
2380 /* XXX: currently, since we do not handle PIC code, we
2381 must relocate the readonly segments */
2382 if (file_type
== TCC_OUTPUT_DLL
) {
2384 put_dt(dynamic
, DT_SONAME
, put_elf_str(dynstr
, s1
->soname
));
2385 put_dt(dynamic
, DT_TEXTREL
, 0);
2389 put_dt(dynamic
, DT_SYMBOLIC
, 0);
2391 /* add necessary space for other entries */
2392 dyninf
.dyn_rel_off
= dynamic
->data_offset
;
2393 dynamic
->data_offset
+= sizeof(ElfW(Dyn
)) * EXTRA_RELITEMS
;
2395 /* still need to build got entries in case of static link */
2396 build_got_entries(s1
);
2400 /* we add a section for symbols */
2401 strsec
= new_section(s1
, ".shstrtab", SHT_STRTAB
, 0);
2402 put_elf_str(strsec
, "");
2404 /* compute number of sections */
2405 shnum
= s1
->nb_sections
;
2407 /* this array is used to reorder sections in the output file */
2408 sec_order
= tcc_malloc(sizeof(int) * shnum
);
2411 /* compute number of program headers */
2414 case TCC_OUTPUT_OBJ
:
2417 case TCC_OUTPUT_EXE
:
2418 if (!s1
->static_link
)
2419 phnum
= 4 + HAVE_PHDR
;
2423 case TCC_OUTPUT_DLL
:
2428 /* Allocate strings for section names */
2429 alloc_sec_names(s1
, file_type
, strsec
);
2431 /* allocate program segment headers */
2432 phdr
= tcc_mallocz(phnum
* sizeof(ElfW(Phdr
)));
2434 /* compute section to program header mapping */
2435 file_offset
= layout_sections(s1
, phdr
, phnum
, interp
, &dyninf
, sec_order
);
2437 /* Fill remaining program header and finalize relocation related to dynamic
2440 fill_unloadable_phdr(phdr
, phnum
, interp
, dynamic
);
2442 dyninf
.dynamic
= dynamic
;
2443 dyninf
.dynstr
= dynstr
;
2445 fill_dynamic(s1
, &dyninf
);
2447 /* put in GOT the dynamic section address and relocate PLT */
2448 put32(s1
->got
->data
, dynamic
->sh_addr
);
2449 if (file_type
== TCC_OUTPUT_EXE
2450 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
2451 || file_type
== TCC_OUTPUT_DLL
2456 /* relocate symbols in .dynsym now that final addresses are known */
2457 for_each_elem(s1
->dynsym
, 1, sym
, ElfW(Sym
)) {
2458 /* relocate to PLT if symbol corresponds to a PLT entry */
2459 if (sym
->st_shndx
== SHN_UNDEF
) {
2461 sym
->st_value
+= s1
->plt
->sh_addr
;
2462 } else if (sym
->st_shndx
< SHN_LORESERVE
) {
2463 /* do symbol relocation */
2464 sym
->st_value
+= s1
->sections
[sym
->st_shndx
]->sh_addr
;
2470 /* if building executable or DLL, then relocate each section
2471 except the GOT which is already relocated */
2472 if (file_type
!= TCC_OUTPUT_OBJ
) {
2473 ret
= final_sections_reloc(s1
);
2478 /* Perform relocation to GOT or PLTÂ entries */
2479 if (file_type
== TCC_OUTPUT_EXE
&& s1
->static_link
)
2482 /* Create the ELF file with name 'filename' */
2483 ret
= tcc_write_elf_file(s1
, filename
, phnum
, phdr
, file_offset
, sec_order
);
2485 tcc_free(s1
->symtab_to_dynsym
);
2486 tcc_free(sec_order
);
2488 tcc_free(s1
->sym_attrs
);
2489 s1
->sym_attrs
= NULL
;
2493 LIBTCCAPI
int tcc_output_file(TCCState
*s
, const char *filename
)
2496 #ifdef TCC_TARGET_PE
2497 if (s
->output_type
!= TCC_OUTPUT_OBJ
) {
2498 ret
= pe_output_file(s
, filename
);
2501 ret
= elf_output_file(s
, filename
);
2505 static void *load_data(int fd
, unsigned long file_offset
, unsigned long size
)
2509 data
= tcc_malloc(size
);
2510 lseek(fd
, file_offset
, SEEK_SET
);
2511 read(fd
, data
, size
);
2515 typedef struct SectionMergeInfo
{
2516 Section
*s
; /* corresponding existing section */
2517 unsigned long offset
; /* offset of the new section in the existing section */
2518 uint8_t new_section
; /* true if section 's' was added */
2519 uint8_t link_once
; /* true if link once section */
2522 /* load an object file and merge it with current files */
2523 /* XXX: handle correctly stab (debug) info */
2524 ST_FUNC
int tcc_load_object_file(TCCState
*s1
,
2525 int fd
, unsigned long file_offset
)
2528 ElfW(Shdr
) *shdr
, *sh
;
2529 int size
, i
, j
, offset
, offseti
, nb_syms
, sym_index
, ret
;
2530 unsigned char *strsec
, *strtab
;
2531 int *old_to_new_syms
;
2532 char *sh_name
, *name
;
2533 SectionMergeInfo
*sm_table
, *sm
;
2534 ElfW(Sym
) *sym
, *symtab
;
2541 stab_index
= stabstr_index
= 0;
2543 if (read(fd
, &ehdr
, sizeof(ehdr
)) != sizeof(ehdr
))
2545 if (ehdr
.e_ident
[0] != ELFMAG0
||
2546 ehdr
.e_ident
[1] != ELFMAG1
||
2547 ehdr
.e_ident
[2] != ELFMAG2
||
2548 ehdr
.e_ident
[3] != ELFMAG3
)
2550 /* test if object file */
2551 if (ehdr
.e_type
!= ET_REL
)
2553 /* test CPU specific stuff */
2554 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2555 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2557 tcc_error_noabort("invalid object file");
2561 shdr
= load_data(fd
, file_offset
+ ehdr
.e_shoff
,
2562 sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2563 sm_table
= tcc_mallocz(sizeof(SectionMergeInfo
) * ehdr
.e_shnum
);
2565 /* load section names */
2566 sh
= &shdr
[ehdr
.e_shstrndx
];
2567 strsec
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2569 /* load symtab and strtab */
2570 old_to_new_syms
= NULL
;
2574 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2576 if (sh
->sh_type
== SHT_SYMTAB
) {
2578 tcc_error_noabort("object must contain only one symtab");
2583 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2584 symtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2585 sm_table
[i
].s
= symtab_section
;
2587 /* now load strtab */
2588 sh
= &shdr
[sh
->sh_link
];
2589 strtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2593 /* now examine each section and try to merge its content with the
2595 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2596 /* no need to examine section name strtab */
2597 if (i
== ehdr
.e_shstrndx
)
2600 sh_name
= (char *) strsec
+ sh
->sh_name
;
2601 /* ignore sections types we do not handle */
2602 if (sh
->sh_type
!= SHT_PROGBITS
&&
2603 sh
->sh_type
!= SHT_RELX
&&
2605 sh
->sh_type
!= SHT_ARM_EXIDX
&&
2607 sh
->sh_type
!= SHT_NOBITS
&&
2608 sh
->sh_type
!= SHT_PREINIT_ARRAY
&&
2609 sh
->sh_type
!= SHT_INIT_ARRAY
&&
2610 sh
->sh_type
!= SHT_FINI_ARRAY
&&
2611 strcmp(sh_name
, ".stabstr")
2614 if (sh
->sh_addralign
< 1)
2615 sh
->sh_addralign
= 1;
2616 /* find corresponding section, if any */
2617 for(j
= 1; j
< s1
->nb_sections
;j
++) {
2618 s
= s1
->sections
[j
];
2619 if (!strcmp(s
->name
, sh_name
)) {
2620 if (!strncmp(sh_name
, ".gnu.linkonce",
2621 sizeof(".gnu.linkonce") - 1)) {
2622 /* if a 'linkonce' section is already present, we
2623 do not add it again. It is a little tricky as
2624 symbols can still be defined in
2626 sm_table
[i
].link_once
= 1;
2633 /* not found: create new section */
2634 s
= new_section(s1
, sh_name
, sh
->sh_type
, sh
->sh_flags
);
2635 /* take as much info as possible from the section. sh_link and
2636 sh_info will be updated later */
2637 s
->sh_addralign
= sh
->sh_addralign
;
2638 s
->sh_entsize
= sh
->sh_entsize
;
2639 sm_table
[i
].new_section
= 1;
2641 if (sh
->sh_type
!= s
->sh_type
) {
2642 tcc_error_noabort("invalid section type");
2646 /* align start of section */
2647 offset
= s
->data_offset
;
2649 if (0 == strcmp(sh_name
, ".stab")) {
2653 if (0 == strcmp(sh_name
, ".stabstr")) {
2658 size
= sh
->sh_addralign
- 1;
2659 offset
= (offset
+ size
) & ~size
;
2660 if (sh
->sh_addralign
> s
->sh_addralign
)
2661 s
->sh_addralign
= sh
->sh_addralign
;
2662 s
->data_offset
= offset
;
2664 sm_table
[i
].offset
= offset
;
2666 /* concatenate sections */
2668 if (sh
->sh_type
!= SHT_NOBITS
) {
2670 lseek(fd
, file_offset
+ sh
->sh_offset
, SEEK_SET
);
2671 ptr
= section_ptr_add(s
, size
);
2672 read(fd
, ptr
, size
);
2674 s
->data_offset
+= size
;
2679 /* gr relocate stab strings */
2680 if (stab_index
&& stabstr_index
) {
2683 s
= sm_table
[stab_index
].s
;
2684 a
= (Stab_Sym
*)(s
->data
+ sm_table
[stab_index
].offset
);
2685 b
= (Stab_Sym
*)(s
->data
+ s
->data_offset
);
2686 o
= sm_table
[stabstr_index
].offset
;
2688 a
->n_strx
+= o
, a
++;
2691 /* second short pass to update sh_link and sh_info fields of new
2693 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2695 if (!s
|| !sm_table
[i
].new_section
)
2698 if (sh
->sh_link
> 0)
2699 s
->link
= sm_table
[sh
->sh_link
].s
;
2700 if (sh
->sh_type
== SHT_RELX
) {
2701 s
->sh_info
= sm_table
[sh
->sh_info
].s
->sh_num
;
2702 /* update backward link */
2703 s1
->sections
[s
->sh_info
]->reloc
= s
;
2708 /* resolve symbols */
2709 old_to_new_syms
= tcc_mallocz(nb_syms
* sizeof(int));
2712 for(i
= 1; i
< nb_syms
; i
++, sym
++) {
2713 if (sym
->st_shndx
!= SHN_UNDEF
&&
2714 sym
->st_shndx
< SHN_LORESERVE
) {
2715 sm
= &sm_table
[sym
->st_shndx
];
2716 if (sm
->link_once
) {
2717 /* if a symbol is in a link once section, we use the
2718 already defined symbol. It is very important to get
2719 correct relocations */
2720 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
2721 name
= (char *) strtab
+ sym
->st_name
;
2722 sym_index
= find_elf_sym(symtab_section
, name
);
2724 old_to_new_syms
[i
] = sym_index
;
2728 /* if no corresponding section added, no need to add symbol */
2731 /* convert section number */
2732 sym
->st_shndx
= sm
->s
->sh_num
;
2734 sym
->st_value
+= sm
->offset
;
2737 name
= (char *) strtab
+ sym
->st_name
;
2738 sym_index
= add_elf_sym(symtab_section
, sym
->st_value
, sym
->st_size
,
2739 sym
->st_info
, sym
->st_other
,
2740 sym
->st_shndx
, name
);
2741 old_to_new_syms
[i
] = sym_index
;
2744 /* third pass to patch relocation entries */
2745 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2750 offset
= sm_table
[i
].offset
;
2751 switch(s
->sh_type
) {
2753 /* take relocation offset information */
2754 offseti
= sm_table
[sh
->sh_info
].offset
;
2755 for_each_elem(s
, (offset
/ sizeof(*rel
)), rel
, ElfW_Rel
) {
2758 /* convert symbol index */
2759 type
= ELFW(R_TYPE
)(rel
->r_info
);
2760 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
2761 /* NOTE: only one symtab assumed */
2762 if (sym_index
>= nb_syms
)
2764 sym_index
= old_to_new_syms
[sym_index
];
2765 /* ignore link_once in rel section. */
2766 if (!sym_index
&& !sm
->link_once
2767 #ifdef TCC_TARGET_ARM
2768 && type
!= R_ARM_V4BX
2772 tcc_error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
2773 i
, strsec
+ sh
->sh_name
, rel
->r_offset
);
2776 rel
->r_info
= ELFW(R_INFO
)(sym_index
, type
);
2777 /* offset the relocation offset */
2778 rel
->r_offset
+= offseti
;
2779 #ifdef TCC_TARGET_ARM
2780 /* Jumps and branches from a Thumb code to a PLT entry need
2781 special handling since PLT entries are ARM code.
2782 Unconditional bl instructions referencing PLT entries are
2783 handled by converting these instructions into blx
2784 instructions. Other case of instructions referencing a PLT
2785 entry require to add a Thumb stub before the PLT entry to
2786 switch to ARM mode. We set bit plt_thumb_stub of the
2787 attribute of a symbol to indicate such a case. */
2788 if (type
== R_ARM_THM_JUMP24
)
2789 alloc_sym_attr(s1
, sym_index
)->plt_thumb_stub
= 1;
2802 tcc_free(old_to_new_syms
);
2809 typedef struct ArchiveHeader
{
2810 char ar_name
[16]; /* name of this member */
2811 char ar_date
[12]; /* file mtime */
2812 char ar_uid
[6]; /* owner uid; printed as decimal */
2813 char ar_gid
[6]; /* owner gid; printed as decimal */
2814 char ar_mode
[8]; /* file mode, printed as octal */
2815 char ar_size
[10]; /* file size, printed as decimal */
2816 char ar_fmag
[2]; /* should contain ARFMAG */
2819 static int get_be32(const uint8_t *b
)
2821 return b
[3] | (b
[2] << 8) | (b
[1] << 16) | (b
[0] << 24);
2824 /* load only the objects which resolve undefined symbols */
2825 static int tcc_load_alacarte(TCCState
*s1
, int fd
, int size
)
2827 int i
, bound
, nsyms
, sym_index
, off
, ret
;
2829 const char *ar_names
, *p
;
2830 const uint8_t *ar_index
;
2833 data
= tcc_malloc(size
);
2834 if (read(fd
, data
, size
) != size
)
2836 nsyms
= get_be32(data
);
2837 ar_index
= data
+ 4;
2838 ar_names
= (char *) ar_index
+ nsyms
* 4;
2842 for(p
= ar_names
, i
= 0; i
< nsyms
; i
++, p
+= strlen(p
)+1) {
2843 sym_index
= find_elf_sym(symtab_section
, p
);
2845 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
2846 if(sym
->st_shndx
== SHN_UNDEF
) {
2847 off
= get_be32(ar_index
+ i
* 4) + sizeof(ArchiveHeader
);
2849 lseek(fd
, off
, SEEK_SET
);
2850 if(tcc_load_object_file(s1
, fd
, off
) < 0) {
2865 /* load a '.a' file */
2866 ST_FUNC
int tcc_load_archive(TCCState
*s1
, int fd
)
2873 unsigned long file_offset
;
2875 /* skip magic which was already checked */
2876 read(fd
, magic
, sizeof(magic
));
2879 len
= read(fd
, &hdr
, sizeof(hdr
));
2882 if (len
!= sizeof(hdr
)) {
2883 tcc_error_noabort("invalid archive");
2886 memcpy(ar_size
, hdr
.ar_size
, sizeof(hdr
.ar_size
));
2887 ar_size
[sizeof(hdr
.ar_size
)] = '\0';
2888 size
= strtol(ar_size
, NULL
, 0);
2889 memcpy(ar_name
, hdr
.ar_name
, sizeof(hdr
.ar_name
));
2890 for(i
= sizeof(hdr
.ar_name
) - 1; i
>= 0; i
--) {
2891 if (ar_name
[i
] != ' ')
2894 ar_name
[i
+ 1] = '\0';
2895 file_offset
= lseek(fd
, 0, SEEK_CUR
);
2897 size
= (size
+ 1) & ~1;
2898 if (!strcmp(ar_name
, "/")) {
2899 /* coff symbol table : we handle it */
2900 if(s1
->alacarte_link
)
2901 return tcc_load_alacarte(s1
, fd
, size
);
2902 } else if (!strcmp(ar_name
, "//") ||
2903 !strcmp(ar_name
, "__.SYMDEF") ||
2904 !strcmp(ar_name
, "__.SYMDEF/") ||
2905 !strcmp(ar_name
, "ARFILENAMES/")) {
2906 /* skip symbol table or archive names */
2908 if (tcc_load_object_file(s1
, fd
, file_offset
) < 0)
2911 lseek(fd
, file_offset
+ size
, SEEK_SET
);
2916 #ifndef TCC_TARGET_PE
2917 /* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
2918 is referenced by the user (so it should be added as DT_NEEDED in
2919 the generated ELF file) */
2920 ST_FUNC
int tcc_load_dll(TCCState
*s1
, int fd
, const char *filename
, int level
)
2923 ElfW(Shdr
) *shdr
, *sh
, *sh1
;
2924 int i
, j
, nb_syms
, nb_dts
, sym_bind
, ret
;
2925 ElfW(Sym
) *sym
, *dynsym
;
2926 ElfW(Dyn
) *dt
, *dynamic
;
2927 unsigned char *dynstr
;
2928 const char *name
, *soname
;
2929 DLLReference
*dllref
;
2931 read(fd
, &ehdr
, sizeof(ehdr
));
2933 /* test CPU specific stuff */
2934 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2935 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2936 tcc_error_noabort("bad architecture");
2941 shdr
= load_data(fd
, ehdr
.e_shoff
, sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2943 /* load dynamic section and dynamic symbols */
2947 dynsym
= NULL
; /* avoid warning */
2948 dynstr
= NULL
; /* avoid warning */
2949 for(i
= 0, sh
= shdr
; i
< ehdr
.e_shnum
; i
++, sh
++) {
2950 switch(sh
->sh_type
) {
2952 nb_dts
= sh
->sh_size
/ sizeof(ElfW(Dyn
));
2953 dynamic
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2956 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2957 dynsym
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2958 sh1
= &shdr
[sh
->sh_link
];
2959 dynstr
= load_data(fd
, sh1
->sh_offset
, sh1
->sh_size
);
2966 /* compute the real library name */
2967 soname
= tcc_basename(filename
);
2969 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
2970 if (dt
->d_tag
== DT_SONAME
) {
2971 soname
= (char *) dynstr
+ dt
->d_un
.d_val
;
2975 /* if the dll is already loaded, do not load it */
2976 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2977 dllref
= s1
->loaded_dlls
[i
];
2978 if (!strcmp(soname
, dllref
->name
)) {
2979 /* but update level if needed */
2980 if (level
< dllref
->level
)
2981 dllref
->level
= level
;
2987 /* add the dll and its level */
2988 dllref
= tcc_mallocz(sizeof(DLLReference
) + strlen(soname
));
2989 dllref
->level
= level
;
2990 strcpy(dllref
->name
, soname
);
2991 dynarray_add((void ***)&s1
->loaded_dlls
, &s1
->nb_loaded_dlls
, dllref
);
2993 /* add dynamic symbols in dynsym_section */
2994 for(i
= 1, sym
= dynsym
+ 1; i
< nb_syms
; i
++, sym
++) {
2995 sym_bind
= ELFW(ST_BIND
)(sym
->st_info
);
2996 if (sym_bind
== STB_LOCAL
)
2998 name
= (char *) dynstr
+ sym
->st_name
;
2999 add_elf_sym(s1
->dynsymtab_section
, sym
->st_value
, sym
->st_size
,
3000 sym
->st_info
, sym
->st_other
, sym
->st_shndx
, name
);
3003 /* load all referenced DLLs */
3004 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
3007 name
= (char *) dynstr
+ dt
->d_un
.d_val
;
3008 for(j
= 0; j
< s1
->nb_loaded_dlls
; j
++) {
3009 dllref
= s1
->loaded_dlls
[j
];
3010 if (!strcmp(name
, dllref
->name
))
3011 goto already_loaded
;
3013 if (tcc_add_dll(s1
, name
, AFF_REFERENCED_DLL
) < 0) {
3014 tcc_error_noabort("referenced dll '%s' not found", name
);
3031 #define LD_TOK_NAME 256
3032 #define LD_TOK_EOF (-1)
3034 /* return next ld script token */
3035 static int ld_next(TCCState
*s1
, char *name
, int name_size
)
3053 file
->buf_ptr
= parse_comment(file
->buf_ptr
);
3054 ch
= file
->buf_ptr
[0];
3062 /* case 'a' ... 'z': */
3089 /* case 'A' ... 'z': */
3124 if (!((ch
>= 'a' && ch
<= 'z') ||
3125 (ch
>= 'A' && ch
<= 'Z') ||
3126 (ch
>= '0' && ch
<= '9') ||
3127 strchr("/.-_+=$:\\,~", ch
)))
3129 if ((q
- name
) < name_size
- 1) {
3148 static int ld_add_file(TCCState
*s1
, const char filename
[])
3152 ret
= tcc_add_file_internal(s1
, filename
, 0);
3154 ret
= tcc_add_dll(s1
, filename
, 0);
3158 static inline int new_undef_syms(void)
3161 ret
= new_undef_sym
;
3166 static int ld_add_file_list(TCCState
*s1
, const char *cmd
, int as_needed
)
3168 char filename
[1024], libname
[1024];
3169 int t
, group
, nblibs
= 0, ret
= 0;
3172 group
= !strcmp(cmd
, "GROUP");
3175 t
= ld_next(s1
, filename
, sizeof(filename
));
3178 t
= ld_next(s1
, filename
, sizeof(filename
));
3181 if (t
== LD_TOK_EOF
) {
3182 tcc_error_noabort("unexpected end of file");
3184 goto lib_parse_error
;
3185 } else if (t
== ')') {
3187 } else if (t
== '-') {
3188 t
= ld_next(s1
, filename
, sizeof(filename
));
3189 if ((t
!= LD_TOK_NAME
) || (filename
[0] != 'l')) {
3190 tcc_error_noabort("library name expected");
3192 goto lib_parse_error
;
3194 pstrcpy(libname
, sizeof libname
, &filename
[1]);
3195 if (s1
->static_link
) {
3196 snprintf(filename
, sizeof filename
, "lib%s.a", libname
);
3198 snprintf(filename
, sizeof filename
, "lib%s.so", libname
);
3200 } else if (t
!= LD_TOK_NAME
) {
3201 tcc_error_noabort("filename expected");
3203 goto lib_parse_error
;
3205 if (!strcmp(filename
, "AS_NEEDED")) {
3206 ret
= ld_add_file_list(s1
, cmd
, 1);
3208 goto lib_parse_error
;
3210 /* TODO: Implement AS_NEEDED support. Ignore it for now */
3212 ret
= ld_add_file(s1
, filename
);
3214 goto lib_parse_error
;
3216 /* Add the filename *and* the libname to avoid future conversions */
3217 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(filename
));
3218 if (libname
[0] != '\0')
3219 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(libname
));
3223 t
= ld_next(s1
, filename
, sizeof(filename
));
3225 t
= ld_next(s1
, filename
, sizeof(filename
));
3228 if (group
&& !as_needed
) {
3229 while (new_undef_syms()) {
3232 for (i
= 0; i
< nblibs
; i
++)
3233 ld_add_file(s1
, libs
[i
]);
3237 dynarray_reset(&libs
, &nblibs
);
3241 /* interpret a subset of GNU ldscripts to handle the dummy libc.so
3243 ST_FUNC
int tcc_load_ldscript(TCCState
*s1
)
3246 char filename
[1024];
3249 ch
= file
->buf_ptr
[0];
3252 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3253 if (t
== LD_TOK_EOF
)
3255 else if (t
!= LD_TOK_NAME
)
3257 if (!strcmp(cmd
, "INPUT") ||
3258 !strcmp(cmd
, "GROUP")) {
3259 ret
= ld_add_file_list(s1
, cmd
, 0);
3262 } else if (!strcmp(cmd
, "OUTPUT_FORMAT") ||
3263 !strcmp(cmd
, "TARGET")) {
3264 /* ignore some commands */
3265 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3269 t
= ld_next(s1
, filename
, sizeof(filename
));
3270 if (t
== LD_TOK_EOF
) {
3271 tcc_error_noabort("unexpected end of file");
3273 } else if (t
== ')') {
3283 #endif /* !TCC_TARGET_PE */