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 fprintf(stderr
,"FIXME: handle reloc type %x at %x [%p] to %x\n",
774 type
, (unsigned)addr
, ptr
, (unsigned)val
);
776 #elif defined(TCC_TARGET_C67)
784 /* put the low 16 bits of the absolute address
785 add to what is already there */
787 orig
= ((*(int *)(ptr
)) >> 7) & 0xffff;
788 orig
|= (((*(int *)(ptr
+4)) >> 7) & 0xffff) << 16;
790 /* patch both at once - assumes always in pairs Low - High */
792 *(int *) ptr
= (*(int *) ptr
& (~(0xffff << 7)) ) | (((val
+orig
) & 0xffff) << 7);
793 *(int *)(ptr
+4) = (*(int *)(ptr
+4) & (~(0xffff << 7)) ) | ((((val
+orig
)>>16) & 0xffff) << 7);
799 fprintf(stderr
,"FIXME: handle reloc type %x at %x [%p] to %x\n",
800 type
, (unsigned)addr
, ptr
, (unsigned)val
);
802 #elif defined(TCC_TARGET_X86_64)
804 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
805 qrel
->r_info
= ELFW(R_INFO
)(0, R_X86_64_RELATIVE
);
806 qrel
->r_addend
= *(long long *)ptr
+ val
;
809 *(long long *)ptr
+= val
;
813 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
814 /* XXX: this logic may depend on TCC's codegen
815 now TCC uses R_X86_64_32 even for a 64bit pointer */
816 qrel
->r_info
= ELFW(R_INFO
)(0, R_X86_64_RELATIVE
);
817 qrel
->r_addend
= *(int *)ptr
+ val
;
824 if (s1
->output_type
== TCC_OUTPUT_DLL
) {
826 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
828 qrel
->r_offset
= rel
->r_offset
;
829 qrel
->r_info
= ELFW(R_INFO
)(esym_index
, R_X86_64_PC32
);
830 qrel
->r_addend
= *(int *)ptr
;
836 case R_X86_64_PLT32
: {
838 diff
= (long long)val
- addr
;
839 if (diff
<= -2147483647 || diff
> 2147483647) {
840 #ifdef TCC_HAS_RUNTIME_PLTGOT
841 /* XXX: naive support for over 32bit jump */
842 if (s1
->output_type
== TCC_OUTPUT_MEMORY
) {
843 val
= (add_jmp_table(s1
, val
- rel
->r_addend
) +
848 if (diff
<= -2147483647 || diff
> 2147483647) {
849 tcc_error("internal error: relocation failed");
855 case R_X86_64_GLOB_DAT
:
856 case R_X86_64_JUMP_SLOT
:
857 /* They don't need addend */
858 *(int *)ptr
= val
- rel
->r_addend
;
860 case R_X86_64_GOTPCREL
:
861 #ifdef TCC_HAS_RUNTIME_PLTGOT
862 if (s1
->output_type
== TCC_OUTPUT_MEMORY
) {
863 val
= add_got_table(s1
, val
- rel
->r_addend
) + rel
->r_addend
;
864 *(int *)ptr
+= val
- addr
;
868 *(int *)ptr
+= (s1
->got
->sh_addr
- addr
+
869 s1
->sym_attrs
[sym_index
].got_offset
- 4);
871 case R_X86_64_GOTTPOFF
:
872 *(int *)ptr
+= val
- s1
->got
->sh_addr
;
875 /* we load the got offset */
876 *(int *)ptr
+= s1
->sym_attrs
[sym_index
].got_offset
;
879 #error unsupported processor
883 /* if the relocation is allocated, we change its symbol table */
884 if (sr
->sh_flags
& SHF_ALLOC
)
885 sr
->link
= s1
->dynsym
;
888 /* relocate relocation table in 'sr' */
889 static void relocate_rel(TCCState
*s1
, Section
*sr
)
894 s
= s1
->sections
[sr
->sh_info
];
895 for_each_elem(sr
, 0, rel
, ElfW_Rel
)
896 rel
->r_offset
+= s
->sh_addr
;
899 /* count the number of dynamic relocations so that we can reserve
901 static int prepare_dynamic_rel(TCCState
*s1
, Section
*sr
)
904 int sym_index
, esym_index
, type
, count
;
907 for_each_elem(sr
, 0, rel
, ElfW_Rel
) {
908 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
909 type
= ELFW(R_TYPE
)(rel
->r_info
);
911 #if defined(TCC_TARGET_I386)
913 #elif defined(TCC_TARGET_X86_64)
920 #if defined(TCC_TARGET_I386)
922 #elif defined(TCC_TARGET_X86_64)
925 esym_index
= s1
->symtab_to_dynsym
[sym_index
];
934 /* allocate the section */
935 sr
->sh_flags
|= SHF_ALLOC
;
936 sr
->sh_size
= count
* sizeof(ElfW_Rel
);
941 static struct sym_attr
*alloc_sym_attr(TCCState
*s1
, int index
)
944 struct sym_attr
*tab
;
946 if (index
>= s1
->nb_sym_attrs
) {
947 /* find immediately bigger power of 2 and reallocate array */
951 tab
= tcc_realloc(s1
->sym_attrs
, n
* sizeof(*s1
->sym_attrs
));
953 memset(s1
->sym_attrs
+ s1
->nb_sym_attrs
, 0,
954 (n
- s1
->nb_sym_attrs
) * sizeof(*s1
->sym_attrs
));
955 s1
->nb_sym_attrs
= n
;
957 return &s1
->sym_attrs
[index
];
960 /* XXX: suppress that */
961 static void put32(unsigned char *p
, uint32_t val
)
969 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_ARM) || \
970 defined(TCC_TARGET_X86_64)
971 static uint32_t get32(unsigned char *p
)
973 return p
[0] | (p
[1] << 8) | (p
[2] << 16) | (p
[3] << 24);
977 static void build_got(TCCState
*s1
)
981 /* if no got, then create it */
982 s1
->got
= new_section(s1
, ".got", SHT_PROGBITS
, SHF_ALLOC
| SHF_WRITE
);
983 s1
->got
->sh_entsize
= 4;
984 add_elf_sym(symtab_section
, 0, 4, ELFW(ST_INFO
)(STB_GLOBAL
, STT_OBJECT
),
985 0, s1
->got
->sh_num
, "_GLOBAL_OFFSET_TABLE_");
986 ptr
= section_ptr_add(s1
->got
, 3 * PTR_SIZE
);
988 /* keep space for _DYNAMIC pointer, if present */
990 /* two dummy got entries */
994 /* keep space for _DYNAMIC pointer, if present */
997 /* two dummy got entries */
1005 /* put a got entry corresponding to a symbol in symtab_section. 'size'
1006 and 'info' can be modifed if more precise info comes from the DLL */
1007 static void put_got_entry(TCCState
*s1
,
1008 int reloc_type
, unsigned long size
, int info
,
1011 int index
, need_plt_entry
, got_entry_present
= 0;
1014 unsigned long offset
;
1020 need_plt_entry
= s1
->dynsym
&&
1021 #ifdef TCC_TARGET_X86_64
1022 (reloc_type
== R_X86_64_JUMP_SLOT
);
1023 #elif defined(TCC_TARGET_I386)
1024 (reloc_type
== R_386_JMP_SLOT
);
1025 #elif defined(TCC_TARGET_ARM)
1026 (reloc_type
== R_ARM_JUMP_SLOT
);
1031 /* if a got entry already exists for that symbol, no need to add one */
1032 if (sym_index
< s1
->nb_sym_attrs
&&
1033 s1
->sym_attrs
[sym_index
].got_offset
) {
1034 if (!need_plt_entry
)
1037 got_entry_present
= 1;
1040 alloc_sym_attr(s1
, sym_index
)->got_offset
= s1
->got
->data_offset
;
1043 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1044 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1045 if (s1
->sym_attrs
[sym_index
].has_plt_entry
)
1047 s1
->sym_attrs
[sym_index
].has_plt_entry
= 1;
1048 offset
= sym
->st_value
;
1049 #if defined(TCC_TARGET_I386) || defined(TCC_TARGET_X86_64)
1050 if (need_plt_entry
) {
1055 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1058 /* if we build a DLL, we add a %ebx offset */
1059 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1065 /* add a PLT entry */
1067 if (plt
->data_offset
== 0) {
1068 /* first plt entry */
1069 p
= section_ptr_add(plt
, 16);
1070 p
[0] = 0xff; /* pushl got + PTR_SIZE */
1071 p
[1] = modrm
+ 0x10;
1072 put32(p
+ 2, PTR_SIZE
);
1073 p
[6] = 0xff; /* jmp *(got + PTR_SIZE * 2) */
1075 put32(p
+ 8, PTR_SIZE
* 2);
1078 p
= section_ptr_add(plt
, 16);
1079 p
[0] = 0xff; /* jmp *(got + x) */
1081 put32(p
+ 2, s1
->got
->data_offset
);
1082 p
[6] = 0x68; /* push $xxx */
1083 put32(p
+ 7, (plt
->data_offset
- 32) >> 1);
1084 p
[11] = 0xe9; /* jmp plt_start */
1085 put32(p
+ 12, -(plt
->data_offset
));
1087 /* the symbol is modified so that it will be relocated to
1089 #if !defined(TCC_OUTPUT_DLL_WITH_PLT)
1090 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1092 offset
= plt
->data_offset
- 16;
1094 #elif defined(TCC_TARGET_ARM)
1095 if (need_plt_entry
) {
1099 /* if we build a DLL, we add a %ebx offset */
1100 if (s1
->output_type
== TCC_OUTPUT_DLL
)
1101 tcc_error("DLLs unimplemented!");
1103 /* add a PLT entry */
1105 if (plt
->data_offset
== 0) {
1106 /* first plt entry */
1107 p
= section_ptr_add(plt
, 16);
1108 put32(p
, 0xe52de004); /* push {lr} */
1109 put32(p
+4, 0xe59fe010); /* ldr lr, [pc, #16] */
1110 put32(p
+8, 0xe08fe00e); /* add lr, pc, lr */
1111 put32(p
+12, 0xe5bef008); /* ldr pc, [lr, #8]! */
1114 if (s1
->sym_attrs
[sym_index
].plt_thumb_stub
) {
1115 p
= section_ptr_add(plt
, 20);
1116 put32(p
, 0x4778); /* bx pc */
1117 put32(p
+2, 0x46c0); /* nop */
1120 p
= section_ptr_add(plt
, 16);
1121 put32(p
, 0xe59fc004); /* ldr ip, [pc, #4] ; GOT entry offset */
1122 put32(p
+4, 0xe08fc00c); /* add ip, pc, ip ; addr of GOT entry */
1123 put32(p
+8, 0xe59cf000); /* ldr pc, [ip] ; jump to GOT entry */
1124 put32(p
+12, s1
->got
->data_offset
); /* GOT entry off once patched */
1126 /* the symbol is modified so that it will be relocated to
1128 if (s1
->output_type
== TCC_OUTPUT_EXE
)
1129 offset
= plt
->data_offset
- 16;
1131 #elif defined(TCC_TARGET_C67)
1132 tcc_error("C67 got not implemented");
1134 #error unsupported CPU
1136 index
= put_elf_sym(s1
->dynsym
, offset
,
1137 size
, info
, 0, sym
->st_shndx
, name
);
1138 if (got_entry_present
) {
1139 put_elf_reloc(s1
->dynsym
, s1
->got
,
1140 s1
->sym_attrs
[sym_index
].got_offset
,
1145 /* put a got entry */
1146 put_elf_reloc(s1
->dynsym
, s1
->got
,
1147 s1
->got
->data_offset
,
1150 ptr
= section_ptr_add(s1
->got
, PTR_SIZE
);
1154 /* build GOT and PLT entries */
1155 ST_FUNC
void build_got_entries(TCCState
*s1
)
1160 int i
, type
, reloc_type
, sym_index
;
1162 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1163 s
= s1
->sections
[i
];
1164 if (s
->sh_type
!= SHT_RELX
)
1166 /* no need to handle got relocations */
1167 if (s
->link
!= symtab_section
)
1169 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1170 type
= ELFW(R_TYPE
)(rel
->r_info
);
1172 #if defined(TCC_TARGET_I386)
1179 if (type
== R_386_GOT32
|| type
== R_386_PLT32
) {
1180 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1181 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1182 /* look at the symbol got offset. If none, then add one */
1183 if (type
== R_386_GOT32
)
1184 reloc_type
= R_386_GLOB_DAT
;
1186 reloc_type
= R_386_JMP_SLOT
;
1187 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1191 #elif defined(TCC_TARGET_ARM)
1198 if (type
== R_ARM_GOT32
|| type
== R_ARM_PLT32
) {
1199 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1200 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1201 /* look at the symbol got offset. If none, then add one */
1202 if (type
== R_ARM_GOT32
)
1203 reloc_type
= R_ARM_GLOB_DAT
;
1205 reloc_type
= R_ARM_JUMP_SLOT
;
1206 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1210 case R_ARM_THM_JUMP24
:
1211 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1212 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1213 /* We are relocating a jump from thumb code to arm code */
1214 if (sym
->st_shndx
!= SHN_UNDEF
&& !(sym
->st_value
& 1)) {
1217 char *name
, buf
[1024];
1218 Section
*text_section
;
1220 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1221 text_section
= s1
->sections
[sym
->st_shndx
];
1222 /* Modify reloc to target a thumb stub to switch to ARM */
1223 snprintf(buf
, sizeof(buf
), "%s_from_thumb", name
);
1224 index
= put_elf_sym(symtab_section
,
1225 text_section
->data_offset
+ 1,
1226 sym
->st_size
, sym
->st_info
, 0,
1227 sym
->st_shndx
, buf
);
1228 rel
->r_info
= ELFW(R_INFO
)(index
, type
);
1229 /* Create a thumb stub fonction to switch to ARM mode */
1230 put_elf_reloc(symtab_section
, text_section
,
1231 text_section
->data_offset
+ 4, R_ARM_JUMP24
,
1233 p
= section_ptr_add(text_section
, 8);
1234 put32(p
, 0x4778); /* bx pc */
1235 put32(p
+2, 0x46c0); /* nop */
1236 put32(p
+4, 0xeafffffe); /* b $sym */
1238 #elif defined(TCC_TARGET_C67)
1245 if (type
== R_C60_GOT32
|| type
== R_C60_PLT32
) {
1246 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1247 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1248 /* look at the symbol got offset. If none, then add one */
1249 if (type
== R_C60_GOT32
)
1250 reloc_type
= R_C60_GLOB_DAT
;
1252 reloc_type
= R_C60_JMP_SLOT
;
1253 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1257 #elif defined(TCC_TARGET_X86_64)
1258 case R_X86_64_GOT32
:
1259 case R_X86_64_GOTTPOFF
:
1260 case R_X86_64_GOTPCREL
:
1261 case R_X86_64_PLT32
:
1264 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
||
1265 type
== R_X86_64_PLT32
) {
1266 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
1267 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1268 /* look at the symbol got offset. If none, then add one */
1269 if (type
== R_X86_64_GOT32
|| type
== R_X86_64_GOTPCREL
)
1270 reloc_type
= R_X86_64_GLOB_DAT
;
1272 reloc_type
= R_X86_64_JUMP_SLOT
;
1273 put_got_entry(s1
, reloc_type
, sym
->st_size
, sym
->st_info
,
1278 #error unsupported CPU
1287 ST_FUNC Section
*new_symtab(TCCState
*s1
,
1288 const char *symtab_name
, int sh_type
, int sh_flags
,
1289 const char *strtab_name
,
1290 const char *hash_name
, int hash_sh_flags
)
1292 Section
*symtab
, *strtab
, *hash
;
1293 int *ptr
, nb_buckets
;
1295 symtab
= new_section(s1
, symtab_name
, sh_type
, sh_flags
);
1296 symtab
->sh_entsize
= sizeof(ElfW(Sym
));
1297 strtab
= new_section(s1
, strtab_name
, SHT_STRTAB
, sh_flags
);
1298 put_elf_str(strtab
, "");
1299 symtab
->link
= strtab
;
1300 put_elf_sym(symtab
, 0, 0, 0, 0, 0, NULL
);
1304 hash
= new_section(s1
, hash_name
, SHT_HASH
, hash_sh_flags
);
1305 hash
->sh_entsize
= sizeof(int);
1306 symtab
->hash
= hash
;
1307 hash
->link
= symtab
;
1309 ptr
= section_ptr_add(hash
, (2 + nb_buckets
+ 1) * sizeof(int));
1310 ptr
[0] = nb_buckets
;
1312 memset(ptr
+ 2, 0, (nb_buckets
+ 1) * sizeof(int));
1316 /* put dynamic tag */
1317 static void put_dt(Section
*dynamic
, int dt
, addr_t val
)
1320 dyn
= section_ptr_add(dynamic
, sizeof(ElfW(Dyn
)));
1322 dyn
->d_un
.d_val
= val
;
1325 static void add_init_array_defines(TCCState
*s1
, const char *section_name
)
1329 char sym_start
[1024];
1332 snprintf(sym_start
, sizeof(sym_start
), "__%s_start", section_name
+ 1);
1333 snprintf(sym_end
, sizeof(sym_end
), "__%s_end", section_name
+ 1);
1335 s
= find_section(s1
, section_name
);
1340 end_offset
= s
->data_offset
;
1343 add_elf_sym(symtab_section
,
1345 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1346 s
->sh_num
, sym_start
);
1347 add_elf_sym(symtab_section
,
1349 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1350 s
->sh_num
, sym_end
);
1353 ST_FUNC
void tcc_add_bcheck(TCCState
*s1
)
1355 #ifdef CONFIG_TCC_BCHECK
1357 Section
*init_section
;
1358 unsigned char *pinit
;
1361 if (0 == s1
->do_bounds_check
)
1364 /* XXX: add an object file to do that */
1365 ptr
= section_ptr_add(bounds_section
, sizeof(unsigned long));
1367 add_elf_sym(symtab_section
, 0, 0,
1368 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1369 bounds_section
->sh_num
, "__bounds_start");
1370 #ifdef TCC_TARGET_I386
1371 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
) {
1372 /* add 'call __bound_init()' in .init section */
1373 init_section
= find_section(s1
, ".init");
1374 pinit
= section_ptr_add(init_section
, 5);
1376 put32(pinit
+ 1, -4);
1377 sym_index
= find_elf_sym(symtab_section
, "__bound_init");
1378 put_elf_reloc(symtab_section
, init_section
,
1379 init_section
->data_offset
- 4, R_386_PC32
, sym_index
);
1385 static inline int tcc_add_support(TCCState
*s1
, const char *filename
)
1388 snprintf(buf
, sizeof(buf
), "%s/%s", s1
->tcc_lib_path
, filename
);
1389 return tcc_add_file(s1
, buf
);
1392 /* add tcc runtime libraries */
1393 ST_FUNC
void tcc_add_runtime(TCCState
*s1
)
1396 if (!s1
->nostdlib
) {
1397 tcc_add_library(s1
, "c");
1398 #ifdef CONFIG_USE_LIBGCC
1399 if (!s1
->static_link
) {
1400 tcc_add_file(s1
, TCC_LIBGCC
);
1401 tcc_add_support(s1
, "libtcc1.a");
1403 tcc_add_support(s1
, "libtcc1.a");
1405 tcc_add_support(s1
, "libtcc1.a");
1409 /* tcc_add_bcheck tries to relocate a call to __bound_init in _init so
1410 libtcc1.a must be loaded before for __bound_init to be defined and
1411 crtn.o must be loaded after to not finalize _init too early. */
1414 if (!s1
->nostdlib
) {
1415 /* add crt end if not memory output */
1416 if (s1
->output_type
!= TCC_OUTPUT_MEMORY
)
1417 tcc_add_crt(s1
, "crtn.o");
1421 /* add various standard linker symbols (must be done after the
1422 sections are filled (for example after allocating common
1424 ST_FUNC
void tcc_add_linker_symbols(TCCState
*s1
)
1430 add_elf_sym(symtab_section
,
1431 text_section
->data_offset
, 0,
1432 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1433 text_section
->sh_num
, "_etext");
1434 add_elf_sym(symtab_section
,
1435 data_section
->data_offset
, 0,
1436 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1437 data_section
->sh_num
, "_edata");
1438 add_elf_sym(symtab_section
,
1439 bss_section
->data_offset
, 0,
1440 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1441 bss_section
->sh_num
, "_end");
1442 /* horrible new standard ldscript defines */
1443 add_init_array_defines(s1
, ".preinit_array");
1444 add_init_array_defines(s1
, ".init_array");
1445 add_init_array_defines(s1
, ".fini_array");
1447 /* add start and stop symbols for sections whose name can be
1449 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1450 s
= s1
->sections
[i
];
1451 if (s
->sh_type
== SHT_PROGBITS
&&
1452 (s
->sh_flags
& SHF_ALLOC
)) {
1456 /* check if section name can be expressed in C */
1462 if (!isid(ch
) && !isnum(ch
))
1466 snprintf(buf
, sizeof(buf
), "__start_%s", s
->name
);
1467 add_elf_sym(symtab_section
,
1469 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1471 snprintf(buf
, sizeof(buf
), "__stop_%s", s
->name
);
1472 add_elf_sym(symtab_section
,
1474 ELFW(ST_INFO
)(STB_GLOBAL
, STT_NOTYPE
), 0,
1481 static void tcc_output_binary(TCCState
*s1
, FILE *f
,
1482 const int *sec_order
)
1485 int i
, offset
, size
;
1488 for(i
=1;i
<s1
->nb_sections
;i
++) {
1489 s
= s1
->sections
[sec_order
[i
]];
1490 if (s
->sh_type
!= SHT_NOBITS
&&
1491 (s
->sh_flags
& SHF_ALLOC
)) {
1492 while (offset
< s
->sh_offset
) {
1497 fwrite(s
->data
, 1, size
, f
);
1503 // making this evaluate to true allow valgrind to work on linux
1504 // but when compiled with debug info and then striped
1505 // the compiled programs segfault
1506 // more tought must be applyed here
1507 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1509 #define EXTRA_RELITEMS 14
1511 /* move the relocation value from .dynsym to .got */
1512 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1514 uint32_t *gotd
= (void *)s1
->got
->data
;
1517 gotd
+= 3; /* dummy entries in .got */
1518 /* relocate symbols in .dynsym */
1519 for_each_elem(s
, 1, sym
, ElfW(Sym
)) {
1520 if (sym
->st_shndx
== SHN_UNDEF
) {
1521 *gotd
++ = sym
->st_value
+ 6; /* XXX 6 is magic ? */
1528 #define EXTRA_RELITEMS 9
1530 /* zero plt offsets of weak symbols in .dynsym */
1531 void patch_dynsym_undef(TCCState
*s1
, Section
*s
)
1535 for_each_elem(s
, 1, sym
, ElfW(Sym
))
1536 if (sym
->st_shndx
== SHN_UNDEF
&& ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
)
1541 ST_FUNC
void fill_got_entry(TCCState
*s1
, ElfW_Rel
*rel
)
1543 int sym_index
= ELFW(R_SYM
) (rel
->r_info
);
1544 ElfW(Sym
) *sym
= &((ElfW(Sym
) *) symtab_section
->data
)[sym_index
];
1545 unsigned long offset
;
1547 if (sym_index
>= s1
->nb_sym_attrs
)
1549 offset
= s1
->sym_attrs
[sym_index
].got_offset
;
1550 section_reserve(s1
->got
, offset
+ PTR_SIZE
);
1551 #ifdef TCC_TARGET_X86_64
1552 /* only works for x86-64 */
1553 put32(s1
->got
->data
+ offset
+ 4, sym
->st_value
>> 32);
1555 put32(s1
->got
->data
+ offset
, sym
->st_value
& 0xffffffff);
1558 /* Perform relocation to GOT or PLTÂ entries */
1559 ST_FUNC
void fill_got(TCCState
*s1
)
1565 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1566 s
= s1
->sections
[i
];
1567 if (s
->sh_type
!= SHT_RELX
)
1569 /* no need to handle got relocations */
1570 if (s
->link
!= symtab_section
)
1572 for_each_elem(s
, 0, rel
, ElfW_Rel
) {
1573 switch (ELFW(R_TYPE
) (rel
->r_info
)) {
1574 case R_X86_64_GOT32
:
1575 case R_X86_64_GOTPCREL
:
1576 case R_X86_64_PLT32
:
1577 fill_got_entry(s1
, rel
);
1584 /* Bind symbols of executable: resolve undefined symbols from exported symbols
1585 in shared libraries and export non local defined symbols to shared libraries
1586 if -rdynamic switch was given on command line */
1587 static void bind_exe_dynsyms(TCCState
*s1
)
1590 int sym_index
, index
;
1591 ElfW(Sym
) *sym
, *esym
;
1594 /* Resolve undefined symbols from dynamic symbols. When there is a match:
1595 - if STT_FUNC or STT_GNU_IFUNC symbol -> add it in PLT
1596 - if STT_OBJECT symbol -> add it in .bss section with suitable reloc */
1597 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1598 if (sym
->st_shndx
== SHN_UNDEF
) {
1599 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1600 sym_index
= find_elf_sym(s1
->dynsymtab_section
, name
);
1602 esym
= &((ElfW(Sym
) *)s1
->dynsymtab_section
->data
)[sym_index
];
1603 type
= ELFW(ST_TYPE
)(esym
->st_info
);
1604 if ((type
== STT_FUNC
) || (type
== STT_GNU_IFUNC
)) {
1605 /* Indirect functions shall have STT_FUNC type in executable
1606 * dynsym section. Indeed, a dlsym call following a lazy
1607 * resolution would pick the symbol value from the
1608 * executable dynsym entry which would contain the address
1609 * of the function wanted by the caller of dlsym instead of
1610 * the address of the function that would return that
1612 put_got_entry(s1
, R_JMP_SLOT
, esym
->st_size
,
1613 ELFW(ST_INFO
)(STB_GLOBAL
,STT_FUNC
),
1614 sym
- (ElfW(Sym
) *)symtab_section
->data
);
1615 } else if (type
== STT_OBJECT
) {
1616 unsigned long offset
;
1618 offset
= bss_section
->data_offset
;
1619 /* XXX: which alignment ? */
1620 offset
= (offset
+ 16 - 1) & -16;
1621 index
= put_elf_sym(s1
->dynsym
, offset
, esym
->st_size
,
1622 esym
->st_info
, 0, bss_section
->sh_num
,
1624 /* Ensure R_COPY works for weak symbol aliases */
1625 if (ELFW(ST_BIND
)(esym
->st_info
) == STB_WEAK
) {
1626 for_each_elem(s1
->dynsymtab_section
, 1, dynsym
, ElfW(Sym
)) {
1627 if ((dynsym
->st_value
== esym
->st_value
)
1628 && (ELFW(ST_BIND
)(dynsym
->st_info
) == STB_GLOBAL
)) {
1629 char *dynname
= (char *) s1
->dynsymtab_section
->link
->data
1631 put_elf_sym(s1
->dynsym
, offset
, dynsym
->st_size
,
1633 bss_section
->sh_num
, dynname
);
1638 put_elf_reloc(s1
->dynsym
, bss_section
,
1639 offset
, R_COPY
, index
);
1640 offset
+= esym
->st_size
;
1641 bss_section
->data_offset
= offset
;
1644 /* STB_WEAK undefined symbols are accepted */
1645 /* XXX: _fp_hw seems to be part of the ABI, so we ignore it */
1646 if (ELFW(ST_BIND
)(sym
->st_info
) == STB_WEAK
||
1647 !strcmp(name
, "_fp_hw")) {
1649 tcc_error_noabort("undefined symbol '%s'", name
);
1652 } else if (s1
->rdynamic
&& ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1653 /* if -rdynamic option, then export all non local symbols */
1654 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1655 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
, sym
->st_info
,
1656 0, sym
->st_shndx
, name
);
1661 /* Bind symbols of libraries: export non local symbols of executable that
1662 resolve undefined symbols of shared libraries */
1663 static void bind_libs_dynsyms(TCCState
*s1
)
1667 ElfW(Sym
) *sym
, *esym
;
1669 /* now look at unresolved dynamic symbols and export
1670 corresponding symbol */
1671 for_each_elem(s1
->dynsymtab_section
, 1, esym
, ElfW(Sym
)) {
1672 if (esym
->st_shndx
== SHN_UNDEF
) {
1673 name
= (char *) s1
->dynsymtab_section
->link
->data
+ esym
->st_name
;
1674 sym_index
= find_elf_sym(symtab_section
, name
);
1676 /* XXX: avoid adding a symbol if already present because of
1678 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
1679 put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1680 sym
->st_info
, 0, sym
->st_shndx
, name
);
1682 /* weak symbols can stay undefined */
1683 if (ELFW(ST_BIND
)(esym
->st_info
) != STB_WEAK
)
1684 tcc_warning("undefined dynamic symbol '%s'", name
);
1690 /* Export all non local symbols (for shared libraries) */
1691 static void export_global_syms(TCCState
*s1
)
1693 int nb_syms
, dynindex
, index
;
1697 nb_syms
= symtab_section
->data_offset
/ sizeof(ElfW(Sym
));
1698 s1
->symtab_to_dynsym
= tcc_mallocz(sizeof(int) * nb_syms
);
1699 for_each_elem(symtab_section
, 1, sym
, ElfW(Sym
)) {
1700 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
1701 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
1702 int type
= ELFW(ST_TYPE
)(sym
->st_info
);
1703 if ((type
== STT_FUNC
|| type
== STT_GNU_IFUNC
)
1704 && sym
->st_shndx
== SHN_UNDEF
) {
1705 int visibility
= ELFW(ST_BIND
)(sym
->st_info
);
1706 put_got_entry(s1
, R_JMP_SLOT
, sym
->st_size
,
1707 ELFW(ST_INFO
)(visibility
, STT_FUNC
),
1708 sym
- (ElfW(Sym
) *) symtab_section
->data
);
1709 } else if (type
== STT_OBJECT
) {
1710 put_got_entry(s1
, R_X86_64_GLOB_DAT
, sym
->st_size
, sym
->st_info
,
1711 sym
- (ElfW(Sym
) *) symtab_section
->data
);
1715 name
= (char *) symtab_section
->link
->data
+ sym
->st_name
;
1716 dynindex
= put_elf_sym(s1
->dynsym
, sym
->st_value
, sym
->st_size
,
1717 sym
->st_info
, 0, sym
->st_shndx
, name
);
1718 index
= sym
- (ElfW(Sym
) *) symtab_section
->data
;
1719 s1
->symtab_to_dynsym
[index
] = dynindex
;
1725 /* relocate the PLT: compute addresses and offsets in the PLT now that final
1726 address for PLT and GOT are known (see fill_program_header) */
1727 static void relocate_plt(TCCState
*s1
)
1732 p_end
= p
+ s1
->plt
->data_offset
;
1734 #if defined(TCC_TARGET_I386)
1735 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1736 put32(p
+ 8, get32(p
+ 8) + s1
->got
->sh_addr
);
1739 put32(p
+ 2, get32(p
+ 2) + s1
->got
->sh_addr
);
1742 #elif defined(TCC_TARGET_X86_64)
1743 int x
= s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 6;
1744 put32(p
+ 2, get32(p
+ 2) + x
);
1745 put32(p
+ 8, get32(p
+ 8) + x
- 6);
1748 put32(p
+ 2, get32(p
+ 2) + x
+ s1
->plt
->data
- p
);
1751 #elif defined(TCC_TARGET_ARM)
1753 x
=s1
->got
->sh_addr
- s1
->plt
->sh_addr
- 12;
1756 if (get32(p
) == 0x46c04778) /* PLT Thumb stub present */
1758 put32(p
+ 12, x
+ get32(p
+ 12) + s1
->plt
->data
- p
);
1761 #elif defined(TCC_TARGET_C67)
1764 #error unsupported CPU
1769 /* Allocate strings for section names and decide if an unallocated section
1772 NOTE: the strsec section comes last, so its size is also correct ! */
1773 static void alloc_sec_names(TCCState
*s1
, int file_type
, Section
*strsec
)
1778 /* Allocate strings for section names */
1779 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1780 s
= s1
->sections
[i
];
1781 s
->sh_name
= put_elf_str(strsec
, s
->name
);
1782 /* when generating a DLL, we include relocations but we may
1784 if (file_type
== TCC_OUTPUT_DLL
&&
1785 s
->sh_type
== SHT_RELX
&&
1786 !(s
->sh_flags
& SHF_ALLOC
)) {
1787 /* gr: avoid bogus relocs for empty (debug) sections */
1788 if (s1
->sections
[s
->sh_info
]->sh_flags
& SHF_ALLOC
)
1789 prepare_dynamic_rel(s1
, s
);
1790 else if (s1
->do_debug
)
1791 s
->sh_size
= s
->data_offset
;
1792 } else if (s1
->do_debug
||
1793 file_type
== TCC_OUTPUT_OBJ
||
1794 (s
->sh_flags
& SHF_ALLOC
) ||
1795 i
== (s1
->nb_sections
- 1)) {
1796 /* we output all sections if debug or object file */
1797 s
->sh_size
= s
->data_offset
;
1802 /* Info to be copied in dynamic section */
1806 unsigned long dyn_rel_off
;
1809 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1815 /* Assign sections to segments and decide how are sections laid out when loaded
1816 in memory. This function also fills corresponding program headers. */
1817 static int layout_sections(TCCState
*s1
, ElfW(Phdr
) *phdr
, int phnum
,
1818 Section
*interp
, struct dyn_inf
*dyninf
,
1821 int i
, j
, k
, file_type
, sh_order_index
, file_offset
;
1827 file_type
= s1
->output_type
;
1829 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
1830 file_offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
1835 if (s1
->has_text_addr
) {
1836 int a_offset
, p_offset
;
1837 addr
= s1
->text_addr
;
1838 /* we ensure that (addr % ELF_PAGE_SIZE) == file_offset %
1840 a_offset
= (int) (addr
& (s1
->section_align
- 1));
1841 p_offset
= file_offset
& (s1
->section_align
- 1);
1842 if (a_offset
< p_offset
)
1843 a_offset
+= s1
->section_align
;
1844 file_offset
+= (a_offset
- p_offset
);
1846 if (file_type
== TCC_OUTPUT_DLL
)
1849 addr
= ELF_START_ADDR
;
1850 /* compute address after headers */
1851 addr
+= (file_offset
& (s1
->section_align
- 1));
1855 /* Leave one program headers for the program interpreter and one for
1856 the program header table itself if needed. These are done later as
1857 they require section layout to be done first. */
1859 ph
+= 1 + HAVE_PHDR
;
1861 /* dynamic relocation table information, for .dynamic section */
1862 dyninf
->rel_addr
= dyninf
->rel_size
= 0;
1863 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1864 dyninf
->bss_addr
= dyninf
->bss_size
= 0;
1867 for(j
= 0; j
< 2; j
++) {
1868 ph
->p_type
= PT_LOAD
;
1870 ph
->p_flags
= PF_R
| PF_X
;
1872 ph
->p_flags
= PF_R
| PF_W
;
1873 ph
->p_align
= s1
->section_align
;
1875 /* Decide the layout of sections loaded in memory. This must
1876 be done before program headers are filled since they contain
1877 info about the layout. We do the following ordering: interp,
1878 symbol tables, relocations, progbits, nobits */
1879 /* XXX: do faster and simpler sorting */
1880 for(k
= 0; k
< 5; k
++) {
1881 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1882 s
= s1
->sections
[i
];
1883 /* compute if section should be included */
1885 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1889 if ((s
->sh_flags
& (SHF_ALLOC
| SHF_WRITE
)) !=
1890 (SHF_ALLOC
| SHF_WRITE
))
1896 } else if (s
->sh_type
== SHT_DYNSYM
||
1897 s
->sh_type
== SHT_STRTAB
||
1898 s
->sh_type
== SHT_HASH
) {
1901 } else if (s
->sh_type
== SHT_RELX
) {
1904 } else if (s
->sh_type
== SHT_NOBITS
) {
1911 sec_order
[sh_order_index
++] = i
;
1913 /* section matches: we align it and add its size */
1915 addr
= (addr
+ s
->sh_addralign
- 1) &
1916 ~(s
->sh_addralign
- 1);
1917 file_offset
+= (int) ( addr
- tmp
);
1918 s
->sh_offset
= file_offset
;
1921 /* update program header infos */
1922 if (ph
->p_offset
== 0) {
1923 ph
->p_offset
= file_offset
;
1925 ph
->p_paddr
= ph
->p_vaddr
;
1927 /* update dynamic relocation infos */
1928 if (s
->sh_type
== SHT_RELX
) {
1929 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
1930 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.got")) {
1931 dyninf
->rel_addr
= addr
;
1932 dyninf
->rel_size
+= s
->sh_size
; /* XXX only first rel. */
1934 if (!strcmp(strsec
->data
+ s
->sh_name
, ".rel.bss")) {
1935 dyninf
->bss_addr
= addr
;
1936 dyninf
->bss_size
= s
->sh_size
; /* XXX only first rel. */
1939 if (dyninf
->rel_size
== 0)
1940 dyninf
->rel_addr
= addr
;
1941 dyninf
->rel_size
+= s
->sh_size
;
1945 if (s
->sh_type
!= SHT_NOBITS
)
1946 file_offset
+= s
->sh_size
;
1949 ph
->p_filesz
= file_offset
- ph
->p_offset
;
1950 ph
->p_memsz
= addr
- ph
->p_vaddr
;
1953 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
) {
1954 /* if in the middle of a page, we duplicate the page in
1955 memory so that one copy is RX and the other is RW */
1956 if ((addr
& (s1
->section_align
- 1)) != 0)
1957 addr
+= s1
->section_align
;
1959 addr
= (addr
+ s1
->section_align
- 1) & ~(s1
->section_align
- 1);
1960 file_offset
= (file_offset
+ s1
->section_align
- 1) &
1961 ~(s1
->section_align
- 1);
1967 /* all other sections come after */
1968 for(i
= 1; i
< s1
->nb_sections
; i
++) {
1969 s
= s1
->sections
[i
];
1970 if (phnum
> 0 && (s
->sh_flags
& SHF_ALLOC
))
1972 sec_order
[sh_order_index
++] = i
;
1974 file_offset
= (file_offset
+ s
->sh_addralign
- 1) &
1975 ~(s
->sh_addralign
- 1);
1976 s
->sh_offset
= file_offset
;
1977 if (s
->sh_type
!= SHT_NOBITS
)
1978 file_offset
+= s
->sh_size
;
1984 static void fill_unloadable_phdr(ElfW(Phdr
) *phdr
, int phnum
, Section
*interp
,
1989 /* if interpreter, then add corresponding program header */
1995 int len
= phnum
* sizeof(ElfW(Phdr
));
1997 ph
->p_type
= PT_PHDR
;
1998 ph
->p_offset
= sizeof(ElfW(Ehdr
));
1999 ph
->p_vaddr
= interp
->sh_addr
- len
;
2000 ph
->p_paddr
= ph
->p_vaddr
;
2001 ph
->p_filesz
= ph
->p_memsz
= len
;
2002 ph
->p_flags
= PF_R
| PF_X
;
2003 ph
->p_align
= 4; /* interp->sh_addralign; */
2007 ph
->p_type
= PT_INTERP
;
2008 ph
->p_offset
= interp
->sh_offset
;
2009 ph
->p_vaddr
= interp
->sh_addr
;
2010 ph
->p_paddr
= ph
->p_vaddr
;
2011 ph
->p_filesz
= interp
->sh_size
;
2012 ph
->p_memsz
= interp
->sh_size
;
2014 ph
->p_align
= interp
->sh_addralign
;
2017 /* if dynamic section, then add corresponding program header */
2019 ph
= &phdr
[phnum
- 1];
2021 ph
->p_type
= PT_DYNAMIC
;
2022 ph
->p_offset
= dynamic
->sh_offset
;
2023 ph
->p_vaddr
= dynamic
->sh_addr
;
2024 ph
->p_paddr
= ph
->p_vaddr
;
2025 ph
->p_filesz
= dynamic
->sh_size
;
2026 ph
->p_memsz
= dynamic
->sh_size
;
2027 ph
->p_flags
= PF_R
| PF_W
;
2028 ph
->p_align
= dynamic
->sh_addralign
;
2032 /* Fill the dynamic section with tags describing the address and size of
2034 static void fill_dynamic(TCCState
*s1
, struct dyn_inf
*dyninf
)
2038 dynamic
= dyninf
->dynamic
;
2040 /* put dynamic section entries */
2041 dynamic
->data_offset
= dyninf
->dyn_rel_off
;
2042 put_dt(dynamic
, DT_HASH
, s1
->dynsym
->hash
->sh_addr
);
2043 put_dt(dynamic
, DT_STRTAB
, dyninf
->dynstr
->sh_addr
);
2044 put_dt(dynamic
, DT_SYMTAB
, s1
->dynsym
->sh_addr
);
2045 put_dt(dynamic
, DT_STRSZ
, dyninf
->dynstr
->data_offset
);
2046 put_dt(dynamic
, DT_SYMENT
, sizeof(ElfW(Sym
)));
2047 #ifdef TCC_TARGET_X86_64
2048 put_dt(dynamic
, DT_RELA
, dyninf
->rel_addr
);
2049 put_dt(dynamic
, DT_RELASZ
, dyninf
->rel_size
);
2050 put_dt(dynamic
, DT_RELAENT
, sizeof(ElfW_Rel
));
2052 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2053 put_dt(dynamic
, DT_PLTGOT
, s1
->got
->sh_addr
);
2054 put_dt(dynamic
, DT_PLTRELSZ
, dyninf
->rel_size
);
2055 put_dt(dynamic
, DT_JMPREL
, dyninf
->rel_addr
);
2056 put_dt(dynamic
, DT_PLTREL
, DT_REL
);
2057 put_dt(dynamic
, DT_REL
, dyninf
->bss_addr
);
2058 put_dt(dynamic
, DT_RELSZ
, dyninf
->bss_size
);
2060 put_dt(dynamic
, DT_REL
, dyninf
->rel_addr
);
2061 put_dt(dynamic
, DT_RELSZ
, dyninf
->rel_size
);
2062 put_dt(dynamic
, DT_RELENT
, sizeof(ElfW_Rel
));
2066 put_dt(dynamic
, DT_DEBUG
, 0);
2067 put_dt(dynamic
, DT_NULL
, 0);
2070 /* Relocate remaining sections and symbols (that is those not related to
2072 static int final_sections_reloc(TCCState
*s1
)
2077 relocate_syms(s1
, 0);
2079 if (s1
->nb_errors
!= 0)
2082 /* relocate sections */
2083 /* XXX: ignore sections with allocated relocations ? */
2084 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2085 s
= s1
->sections
[i
];
2086 if (s
->reloc
&& s
!= s1
->got
)
2087 relocate_section(s1
, s
);
2090 /* relocate relocation entries if the relocation tables are
2091 allocated in the executable */
2092 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2093 s
= s1
->sections
[i
];
2094 if ((s
->sh_flags
& SHF_ALLOC
) &&
2095 s
->sh_type
== SHT_RELX
) {
2096 relocate_rel(s1
, s
);
2102 /* Create an ELF file on disk.
2103 This function handle ELF specific layout requirements */
2104 static void tcc_output_elf(TCCState
*s1
, FILE *f
, int phnum
, ElfW(Phdr
) *phdr
,
2105 int file_offset
, int *sec_order
)
2107 int i
, shnum
, offset
, size
, file_type
;
2110 ElfW(Shdr
) shdr
, *sh
;
2112 file_type
= s1
->output_type
;
2113 shnum
= s1
->nb_sections
;
2115 memset(&ehdr
, 0, sizeof(ehdr
));
2118 ehdr
.e_phentsize
= sizeof(ElfW(Phdr
));
2119 ehdr
.e_phnum
= phnum
;
2120 ehdr
.e_phoff
= sizeof(ElfW(Ehdr
));
2124 file_offset
= (file_offset
+ 3) & -4;
2127 ehdr
.e_ident
[0] = ELFMAG0
;
2128 ehdr
.e_ident
[1] = ELFMAG1
;
2129 ehdr
.e_ident
[2] = ELFMAG2
;
2130 ehdr
.e_ident
[3] = ELFMAG3
;
2131 ehdr
.e_ident
[4] = ELFCLASSW
;
2132 ehdr
.e_ident
[5] = ELFDATA2LSB
;
2133 ehdr
.e_ident
[6] = EV_CURRENT
;
2134 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
2135 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_FREEBSD
;
2137 #ifdef TCC_TARGET_ARM
2139 ehdr
.e_ident
[EI_OSABI
] = 0;
2140 ehdr
.e_flags
= EF_ARM_EABI_VER4
;
2141 if (file_type
== TCC_OUTPUT_EXE
|| file_type
== TCC_OUTPUT_DLL
)
2142 ehdr
.e_flags
|= EF_ARM_HASENTRY
;
2143 if (s1
->float_abi
== ARM_HARD_FLOAT
)
2144 ehdr
.e_flags
|= EF_ARM_VFP_FLOAT
;
2146 ehdr
.e_flags
|= EF_ARM_SOFT_FLOAT
;
2148 ehdr
.e_ident
[EI_OSABI
] = ELFOSABI_ARM
;
2153 case TCC_OUTPUT_EXE
:
2154 ehdr
.e_type
= ET_EXEC
;
2155 ehdr
.e_entry
= get_elf_sym_addr(s1
, "_start", 1);
2157 case TCC_OUTPUT_DLL
:
2158 ehdr
.e_type
= ET_DYN
;
2159 ehdr
.e_entry
= text_section
->sh_addr
; /* XXX: is it correct ? */
2161 case TCC_OUTPUT_OBJ
:
2162 ehdr
.e_type
= ET_REL
;
2165 ehdr
.e_machine
= EM_TCC_TARGET
;
2166 ehdr
.e_version
= EV_CURRENT
;
2167 ehdr
.e_shoff
= file_offset
;
2168 ehdr
.e_ehsize
= sizeof(ElfW(Ehdr
));
2169 ehdr
.e_shentsize
= sizeof(ElfW(Shdr
));
2170 ehdr
.e_shnum
= shnum
;
2171 ehdr
.e_shstrndx
= shnum
- 1;
2173 fwrite(&ehdr
, 1, sizeof(ElfW(Ehdr
)), f
);
2174 fwrite(phdr
, 1, phnum
* sizeof(ElfW(Phdr
)), f
);
2175 offset
= sizeof(ElfW(Ehdr
)) + phnum
* sizeof(ElfW(Phdr
));
2177 sort_syms(s1
, symtab_section
);
2178 for(i
= 1; i
< s1
->nb_sections
; i
++) {
2179 s
= s1
->sections
[sec_order
[i
]];
2180 if (s
->sh_type
!= SHT_NOBITS
) {
2181 if (s
->sh_type
== SHT_DYNSYM
)
2182 patch_dynsym_undef(s1
, s
);
2183 while (offset
< s
->sh_offset
) {
2188 fwrite(s
->data
, 1, size
, f
);
2193 /* output section headers */
2194 while (offset
< ehdr
.e_shoff
) {
2199 for(i
= 0; i
< s1
->nb_sections
; i
++) {
2201 memset(sh
, 0, sizeof(ElfW(Shdr
)));
2202 s
= s1
->sections
[i
];
2204 sh
->sh_name
= s
->sh_name
;
2205 sh
->sh_type
= s
->sh_type
;
2206 sh
->sh_flags
= s
->sh_flags
;
2207 sh
->sh_entsize
= s
->sh_entsize
;
2208 sh
->sh_info
= s
->sh_info
;
2210 sh
->sh_link
= s
->link
->sh_num
;
2211 sh
->sh_addralign
= s
->sh_addralign
;
2212 sh
->sh_addr
= s
->sh_addr
;
2213 sh
->sh_offset
= s
->sh_offset
;
2214 sh
->sh_size
= s
->sh_size
;
2216 fwrite(sh
, 1, sizeof(ElfW(Shdr
)), f
);
2220 /* Write an elf, coff or "binary" file */
2221 static int tcc_write_elf_file(TCCState
*s1
, const char *filename
, int phnum
,
2222 ElfW(Phdr
) *phdr
, int file_offset
, int *sec_order
)
2224 int fd
, mode
, file_type
;
2227 file_type
= s1
->output_type
;
2228 if (file_type
== TCC_OUTPUT_OBJ
)
2233 fd
= open(filename
, O_WRONLY
| O_CREAT
| O_TRUNC
| O_BINARY
, mode
);
2235 tcc_error_noabort("could not write '%s'", filename
);
2238 f
= fdopen(fd
, "wb");
2240 printf("<- %s\n", filename
);
2242 #ifdef TCC_TARGET_COFF
2243 if (s1
->output_format
== TCC_OUTPUT_FORMAT_COFF
)
2244 tcc_output_coff(s1
, f
);
2247 if (s1
->output_format
== TCC_OUTPUT_FORMAT_ELF
)
2248 tcc_output_elf(s1
, f
, phnum
, phdr
, file_offset
, sec_order
);
2250 tcc_output_binary(s1
, f
, sec_order
);
2256 /* Output an elf, coff or binary file */
2257 /* XXX: suppress unneeded sections */
2258 static int elf_output_file(TCCState
*s1
, const char *filename
)
2260 int i
, ret
, phnum
, shnum
, file_type
, file_offset
, *sec_order
;
2261 struct dyn_inf dyninf
;
2264 Section
*strsec
, *interp
, *dynamic
, *dynstr
;
2266 file_type
= s1
->output_type
;
2269 /* if linking, also link in runtime libraries (libc, libgcc, etc.) */
2270 if (file_type
!= TCC_OUTPUT_OBJ
) {
2271 tcc_add_runtime(s1
);
2276 interp
= dynamic
= dynstr
= NULL
; /* avoid warning */
2277 dyninf
.dyn_rel_off
= 0; /* avoid warning */
2279 if (file_type
!= TCC_OUTPUT_OBJ
) {
2280 relocate_common_syms();
2282 tcc_add_linker_symbols(s1
);
2284 if (!s1
->static_link
) {
2285 if (file_type
== TCC_OUTPUT_EXE
) {
2287 /* allow override the dynamic loader */
2288 const char *elfint
= getenv("LD_SO");
2290 elfint
= DEFAULT_ELFINTERP(s1
);
2291 /* add interpreter section only if executable */
2292 interp
= new_section(s1
, ".interp", SHT_PROGBITS
, SHF_ALLOC
);
2293 interp
->sh_addralign
= 1;
2294 ptr
= section_ptr_add(interp
, 1 + strlen(elfint
));
2295 strcpy(ptr
, elfint
);
2298 /* add dynamic symbol table */
2299 s1
->dynsym
= new_symtab(s1
, ".dynsym", SHT_DYNSYM
, SHF_ALLOC
,
2301 ".hash", SHF_ALLOC
);
2302 dynstr
= s1
->dynsym
->link
;
2304 /* add dynamic section */
2305 dynamic
= new_section(s1
, ".dynamic", SHT_DYNAMIC
,
2306 SHF_ALLOC
| SHF_WRITE
);
2307 dynamic
->link
= dynstr
;
2308 dynamic
->sh_entsize
= sizeof(ElfW(Dyn
));
2311 s1
->plt
= new_section(s1
, ".plt", SHT_PROGBITS
,
2312 SHF_ALLOC
| SHF_EXECINSTR
);
2313 s1
->plt
->sh_entsize
= 4;
2317 if (file_type
== TCC_OUTPUT_EXE
) {
2318 bind_exe_dynsyms(s1
);
2320 if (s1
->nb_errors
) {
2325 bind_libs_dynsyms(s1
);
2326 } else /* shared library case: simply export all global symbols */
2327 export_global_syms(s1
);
2329 build_got_entries(s1
);
2331 /* add a list of needed dlls */
2332 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2333 DLLReference
*dllref
= s1
->loaded_dlls
[i
];
2334 if (dllref
->level
== 0)
2335 put_dt(dynamic
, DT_NEEDED
, put_elf_str(dynstr
, dllref
->name
));
2339 put_dt(dynamic
, DT_RPATH
, put_elf_str(dynstr
, s1
->rpath
));
2341 /* XXX: currently, since we do not handle PIC code, we
2342 must relocate the readonly segments */
2343 if (file_type
== TCC_OUTPUT_DLL
) {
2345 put_dt(dynamic
, DT_SONAME
, put_elf_str(dynstr
, s1
->soname
));
2346 put_dt(dynamic
, DT_TEXTREL
, 0);
2350 put_dt(dynamic
, DT_SYMBOLIC
, 0);
2352 /* add necessary space for other entries */
2353 dyninf
.dyn_rel_off
= dynamic
->data_offset
;
2354 dynamic
->data_offset
+= sizeof(ElfW(Dyn
)) * EXTRA_RELITEMS
;
2356 /* still need to build got entries in case of static link */
2357 build_got_entries(s1
);
2361 /* we add a section for symbols */
2362 strsec
= new_section(s1
, ".shstrtab", SHT_STRTAB
, 0);
2363 put_elf_str(strsec
, "");
2365 /* compute number of sections */
2366 shnum
= s1
->nb_sections
;
2368 /* this array is used to reorder sections in the output file */
2369 sec_order
= tcc_malloc(sizeof(int) * shnum
);
2372 /* compute number of program headers */
2375 case TCC_OUTPUT_OBJ
:
2378 case TCC_OUTPUT_EXE
:
2379 if (!s1
->static_link
)
2380 phnum
= 4 + HAVE_PHDR
;
2384 case TCC_OUTPUT_DLL
:
2389 /* Allocate strings for section names */
2390 alloc_sec_names(s1
, file_type
, strsec
);
2392 /* allocate program segment headers */
2393 phdr
= tcc_mallocz(phnum
* sizeof(ElfW(Phdr
)));
2395 /* compute section to program header mapping */
2396 file_offset
= layout_sections(s1
, phdr
, phnum
, interp
, &dyninf
, sec_order
);
2398 /* Fill remaining program header and finalize relocation related to dynamic
2401 fill_unloadable_phdr(phdr
, phnum
, interp
, dynamic
);
2403 dyninf
.dynamic
= dynamic
;
2404 dyninf
.dynstr
= dynstr
;
2406 fill_dynamic(s1
, &dyninf
);
2408 /* put in GOT the dynamic section address and relocate PLT */
2409 put32(s1
->got
->data
, dynamic
->sh_addr
);
2410 if (file_type
== TCC_OUTPUT_EXE
2411 #if defined(TCC_OUTPUT_DLL_WITH_PLT)
2412 || file_type
== TCC_OUTPUT_DLL
2417 /* relocate symbols in .dynsym now that final addresses are known */
2418 for_each_elem(s1
->dynsym
, 1, sym
, ElfW(Sym
)) {
2419 /* relocate to PLT if symbol corresponds to a PLT entry */
2420 if (sym
->st_shndx
== SHN_UNDEF
) {
2422 sym
->st_value
+= s1
->plt
->sh_addr
;
2423 } else if (sym
->st_shndx
< SHN_LORESERVE
) {
2424 /* do symbol relocation */
2425 sym
->st_value
+= s1
->sections
[sym
->st_shndx
]->sh_addr
;
2431 /* if building executable or DLL, then relocate each section
2432 except the GOT which is already relocated */
2433 if (file_type
!= TCC_OUTPUT_OBJ
) {
2434 ret
= final_sections_reloc(s1
);
2439 /* Perform relocation to GOT or PLTÂ entries */
2440 if (file_type
== TCC_OUTPUT_EXE
&& s1
->static_link
)
2443 /* Create the ELF file with name 'filename' */
2444 ret
= tcc_write_elf_file(s1
, filename
, phnum
, phdr
, file_offset
, sec_order
);
2446 tcc_free(s1
->symtab_to_dynsym
);
2447 tcc_free(sec_order
);
2449 tcc_free(s1
->sym_attrs
);
2450 s1
->sym_attrs
= NULL
;
2454 LIBTCCAPI
int tcc_output_file(TCCState
*s
, const char *filename
)
2457 #ifdef TCC_TARGET_PE
2458 if (s
->output_type
!= TCC_OUTPUT_OBJ
) {
2459 ret
= pe_output_file(s
, filename
);
2462 ret
= elf_output_file(s
, filename
);
2466 static void *load_data(int fd
, unsigned long file_offset
, unsigned long size
)
2470 data
= tcc_malloc(size
);
2471 lseek(fd
, file_offset
, SEEK_SET
);
2472 read(fd
, data
, size
);
2476 typedef struct SectionMergeInfo
{
2477 Section
*s
; /* corresponding existing section */
2478 unsigned long offset
; /* offset of the new section in the existing section */
2479 uint8_t new_section
; /* true if section 's' was added */
2480 uint8_t link_once
; /* true if link once section */
2483 /* load an object file and merge it with current files */
2484 /* XXX: handle correctly stab (debug) info */
2485 ST_FUNC
int tcc_load_object_file(TCCState
*s1
,
2486 int fd
, unsigned long file_offset
)
2489 ElfW(Shdr
) *shdr
, *sh
;
2490 int size
, i
, j
, offset
, offseti
, nb_syms
, sym_index
, ret
;
2491 unsigned char *strsec
, *strtab
;
2492 int *old_to_new_syms
;
2493 char *sh_name
, *name
;
2494 SectionMergeInfo
*sm_table
, *sm
;
2495 ElfW(Sym
) *sym
, *symtab
;
2502 stab_index
= stabstr_index
= 0;
2504 if (read(fd
, &ehdr
, sizeof(ehdr
)) != sizeof(ehdr
))
2506 if (ehdr
.e_ident
[0] != ELFMAG0
||
2507 ehdr
.e_ident
[1] != ELFMAG1
||
2508 ehdr
.e_ident
[2] != ELFMAG2
||
2509 ehdr
.e_ident
[3] != ELFMAG3
)
2511 /* test if object file */
2512 if (ehdr
.e_type
!= ET_REL
)
2514 /* test CPU specific stuff */
2515 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2516 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2518 tcc_error_noabort("invalid object file");
2522 shdr
= load_data(fd
, file_offset
+ ehdr
.e_shoff
,
2523 sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2524 sm_table
= tcc_mallocz(sizeof(SectionMergeInfo
) * ehdr
.e_shnum
);
2526 /* load section names */
2527 sh
= &shdr
[ehdr
.e_shstrndx
];
2528 strsec
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2530 /* load symtab and strtab */
2531 old_to_new_syms
= NULL
;
2535 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2537 if (sh
->sh_type
== SHT_SYMTAB
) {
2539 tcc_error_noabort("object must contain only one symtab");
2544 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2545 symtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2546 sm_table
[i
].s
= symtab_section
;
2548 /* now load strtab */
2549 sh
= &shdr
[sh
->sh_link
];
2550 strtab
= load_data(fd
, file_offset
+ sh
->sh_offset
, sh
->sh_size
);
2554 /* now examine each section and try to merge its content with the
2556 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2557 /* no need to examine section name strtab */
2558 if (i
== ehdr
.e_shstrndx
)
2561 sh_name
= (char *) strsec
+ sh
->sh_name
;
2562 /* ignore sections types we do not handle */
2563 if (sh
->sh_type
!= SHT_PROGBITS
&&
2564 sh
->sh_type
!= SHT_RELX
&&
2566 sh
->sh_type
!= SHT_ARM_EXIDX
&&
2568 sh
->sh_type
!= SHT_NOBITS
&&
2569 sh
->sh_type
!= SHT_PREINIT_ARRAY
&&
2570 sh
->sh_type
!= SHT_INIT_ARRAY
&&
2571 sh
->sh_type
!= SHT_FINI_ARRAY
&&
2572 strcmp(sh_name
, ".stabstr")
2575 if (sh
->sh_addralign
< 1)
2576 sh
->sh_addralign
= 1;
2577 /* find corresponding section, if any */
2578 for(j
= 1; j
< s1
->nb_sections
;j
++) {
2579 s
= s1
->sections
[j
];
2580 if (!strcmp(s
->name
, sh_name
)) {
2581 if (!strncmp(sh_name
, ".gnu.linkonce",
2582 sizeof(".gnu.linkonce") - 1)) {
2583 /* if a 'linkonce' section is already present, we
2584 do not add it again. It is a little tricky as
2585 symbols can still be defined in
2587 sm_table
[i
].link_once
= 1;
2594 /* not found: create new section */
2595 s
= new_section(s1
, sh_name
, sh
->sh_type
, sh
->sh_flags
);
2596 /* take as much info as possible from the section. sh_link and
2597 sh_info will be updated later */
2598 s
->sh_addralign
= sh
->sh_addralign
;
2599 s
->sh_entsize
= sh
->sh_entsize
;
2600 sm_table
[i
].new_section
= 1;
2602 if (sh
->sh_type
!= s
->sh_type
) {
2603 tcc_error_noabort("invalid section type");
2607 /* align start of section */
2608 offset
= s
->data_offset
;
2610 if (0 == strcmp(sh_name
, ".stab")) {
2614 if (0 == strcmp(sh_name
, ".stabstr")) {
2619 size
= sh
->sh_addralign
- 1;
2620 offset
= (offset
+ size
) & ~size
;
2621 if (sh
->sh_addralign
> s
->sh_addralign
)
2622 s
->sh_addralign
= sh
->sh_addralign
;
2623 s
->data_offset
= offset
;
2625 sm_table
[i
].offset
= offset
;
2627 /* concatenate sections */
2629 if (sh
->sh_type
!= SHT_NOBITS
) {
2631 lseek(fd
, file_offset
+ sh
->sh_offset
, SEEK_SET
);
2632 ptr
= section_ptr_add(s
, size
);
2633 read(fd
, ptr
, size
);
2635 s
->data_offset
+= size
;
2640 /* gr relocate stab strings */
2641 if (stab_index
&& stabstr_index
) {
2644 s
= sm_table
[stab_index
].s
;
2645 a
= (Stab_Sym
*)(s
->data
+ sm_table
[stab_index
].offset
);
2646 b
= (Stab_Sym
*)(s
->data
+ s
->data_offset
);
2647 o
= sm_table
[stabstr_index
].offset
;
2649 a
->n_strx
+= o
, a
++;
2652 /* second short pass to update sh_link and sh_info fields of new
2654 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2656 if (!s
|| !sm_table
[i
].new_section
)
2659 if (sh
->sh_link
> 0)
2660 s
->link
= sm_table
[sh
->sh_link
].s
;
2661 if (sh
->sh_type
== SHT_RELX
) {
2662 s
->sh_info
= sm_table
[sh
->sh_info
].s
->sh_num
;
2663 /* update backward link */
2664 s1
->sections
[s
->sh_info
]->reloc
= s
;
2669 /* resolve symbols */
2670 old_to_new_syms
= tcc_mallocz(nb_syms
* sizeof(int));
2673 for(i
= 1; i
< nb_syms
; i
++, sym
++) {
2674 if (sym
->st_shndx
!= SHN_UNDEF
&&
2675 sym
->st_shndx
< SHN_LORESERVE
) {
2676 sm
= &sm_table
[sym
->st_shndx
];
2677 if (sm
->link_once
) {
2678 /* if a symbol is in a link once section, we use the
2679 already defined symbol. It is very important to get
2680 correct relocations */
2681 if (ELFW(ST_BIND
)(sym
->st_info
) != STB_LOCAL
) {
2682 name
= (char *) strtab
+ sym
->st_name
;
2683 sym_index
= find_elf_sym(symtab_section
, name
);
2685 old_to_new_syms
[i
] = sym_index
;
2689 /* if no corresponding section added, no need to add symbol */
2692 /* convert section number */
2693 sym
->st_shndx
= sm
->s
->sh_num
;
2695 sym
->st_value
+= sm
->offset
;
2698 name
= (char *) strtab
+ sym
->st_name
;
2699 sym_index
= add_elf_sym(symtab_section
, sym
->st_value
, sym
->st_size
,
2700 sym
->st_info
, sym
->st_other
,
2701 sym
->st_shndx
, name
);
2702 old_to_new_syms
[i
] = sym_index
;
2705 /* third pass to patch relocation entries */
2706 for(i
= 1; i
< ehdr
.e_shnum
; i
++) {
2711 offset
= sm_table
[i
].offset
;
2712 switch(s
->sh_type
) {
2714 /* take relocation offset information */
2715 offseti
= sm_table
[sh
->sh_info
].offset
;
2716 for_each_elem(s
, (offset
/ sizeof(*rel
)), rel
, ElfW_Rel
) {
2719 /* convert symbol index */
2720 type
= ELFW(R_TYPE
)(rel
->r_info
);
2721 sym_index
= ELFW(R_SYM
)(rel
->r_info
);
2722 /* NOTE: only one symtab assumed */
2723 if (sym_index
>= nb_syms
)
2725 sym_index
= old_to_new_syms
[sym_index
];
2726 /* ignore link_once in rel section. */
2727 if (!sym_index
&& !sm
->link_once
2728 #ifdef TCC_TARGET_ARM
2729 && type
!= R_ARM_V4BX
2733 tcc_error_noabort("Invalid relocation entry [%2d] '%s' @ %.8x",
2734 i
, strsec
+ sh
->sh_name
, rel
->r_offset
);
2737 rel
->r_info
= ELFW(R_INFO
)(sym_index
, type
);
2738 /* offset the relocation offset */
2739 rel
->r_offset
+= offseti
;
2740 #ifdef TCC_TARGET_ARM
2741 /* Jumps and branches from a Thumb code to a PLT entry need
2742 special handling since PLT entries are ARM code.
2743 Unconditional bl instructions referencing PLT entries are
2744 handled by converting these instructions into blx
2745 instructions. Other case of instructions referencing a PLT
2746 entry require to add a Thumb stub before the PLT entry to
2747 switch to ARM mode. We set bit plt_thumb_stub of the
2748 attribute of a symbol to indicate such a case. */
2749 if (type
== R_ARM_THM_JUMP24
)
2750 alloc_sym_attr(s1
, sym_index
)->plt_thumb_stub
= 1;
2763 tcc_free(old_to_new_syms
);
2770 typedef struct ArchiveHeader
{
2771 char ar_name
[16]; /* name of this member */
2772 char ar_date
[12]; /* file mtime */
2773 char ar_uid
[6]; /* owner uid; printed as decimal */
2774 char ar_gid
[6]; /* owner gid; printed as decimal */
2775 char ar_mode
[8]; /* file mode, printed as octal */
2776 char ar_size
[10]; /* file size, printed as decimal */
2777 char ar_fmag
[2]; /* should contain ARFMAG */
2780 static int get_be32(const uint8_t *b
)
2782 return b
[3] | (b
[2] << 8) | (b
[1] << 16) | (b
[0] << 24);
2785 /* load only the objects which resolve undefined symbols */
2786 static int tcc_load_alacarte(TCCState
*s1
, int fd
, int size
)
2788 int i
, bound
, nsyms
, sym_index
, off
, ret
;
2790 const char *ar_names
, *p
;
2791 const uint8_t *ar_index
;
2794 data
= tcc_malloc(size
);
2795 if (read(fd
, data
, size
) != size
)
2797 nsyms
= get_be32(data
);
2798 ar_index
= data
+ 4;
2799 ar_names
= (char *) ar_index
+ nsyms
* 4;
2803 for(p
= ar_names
, i
= 0; i
< nsyms
; i
++, p
+= strlen(p
)+1) {
2804 sym_index
= find_elf_sym(symtab_section
, p
);
2806 sym
= &((ElfW(Sym
) *)symtab_section
->data
)[sym_index
];
2807 if(sym
->st_shndx
== SHN_UNDEF
) {
2808 off
= get_be32(ar_index
+ i
* 4) + sizeof(ArchiveHeader
);
2810 lseek(fd
, off
, SEEK_SET
);
2811 if(tcc_load_object_file(s1
, fd
, off
) < 0) {
2826 /* load a '.a' file */
2827 ST_FUNC
int tcc_load_archive(TCCState
*s1
, int fd
)
2834 unsigned long file_offset
;
2836 /* skip magic which was already checked */
2837 read(fd
, magic
, sizeof(magic
));
2840 len
= read(fd
, &hdr
, sizeof(hdr
));
2843 if (len
!= sizeof(hdr
)) {
2844 tcc_error_noabort("invalid archive");
2847 memcpy(ar_size
, hdr
.ar_size
, sizeof(hdr
.ar_size
));
2848 ar_size
[sizeof(hdr
.ar_size
)] = '\0';
2849 size
= strtol(ar_size
, NULL
, 0);
2850 memcpy(ar_name
, hdr
.ar_name
, sizeof(hdr
.ar_name
));
2851 for(i
= sizeof(hdr
.ar_name
) - 1; i
>= 0; i
--) {
2852 if (ar_name
[i
] != ' ')
2855 ar_name
[i
+ 1] = '\0';
2856 file_offset
= lseek(fd
, 0, SEEK_CUR
);
2858 size
= (size
+ 1) & ~1;
2859 if (!strcmp(ar_name
, "/")) {
2860 /* coff symbol table : we handle it */
2861 if(s1
->alacarte_link
)
2862 return tcc_load_alacarte(s1
, fd
, size
);
2863 } else if (!strcmp(ar_name
, "//") ||
2864 !strcmp(ar_name
, "__.SYMDEF") ||
2865 !strcmp(ar_name
, "__.SYMDEF/") ||
2866 !strcmp(ar_name
, "ARFILENAMES/")) {
2867 /* skip symbol table or archive names */
2869 if (tcc_load_object_file(s1
, fd
, file_offset
) < 0)
2872 lseek(fd
, file_offset
+ size
, SEEK_SET
);
2877 #ifndef TCC_TARGET_PE
2878 /* load a DLL and all referenced DLLs. 'level = 0' means that the DLL
2879 is referenced by the user (so it should be added as DT_NEEDED in
2880 the generated ELF file) */
2881 ST_FUNC
int tcc_load_dll(TCCState
*s1
, int fd
, const char *filename
, int level
)
2884 ElfW(Shdr
) *shdr
, *sh
, *sh1
;
2885 int i
, j
, nb_syms
, nb_dts
, sym_bind
, ret
;
2886 ElfW(Sym
) *sym
, *dynsym
;
2887 ElfW(Dyn
) *dt
, *dynamic
;
2888 unsigned char *dynstr
;
2889 const char *name
, *soname
;
2890 DLLReference
*dllref
;
2892 read(fd
, &ehdr
, sizeof(ehdr
));
2894 /* test CPU specific stuff */
2895 if (ehdr
.e_ident
[5] != ELFDATA2LSB
||
2896 ehdr
.e_machine
!= EM_TCC_TARGET
) {
2897 tcc_error_noabort("bad architecture");
2902 shdr
= load_data(fd
, ehdr
.e_shoff
, sizeof(ElfW(Shdr
)) * ehdr
.e_shnum
);
2904 /* load dynamic section and dynamic symbols */
2908 dynsym
= NULL
; /* avoid warning */
2909 dynstr
= NULL
; /* avoid warning */
2910 for(i
= 0, sh
= shdr
; i
< ehdr
.e_shnum
; i
++, sh
++) {
2911 switch(sh
->sh_type
) {
2913 nb_dts
= sh
->sh_size
/ sizeof(ElfW(Dyn
));
2914 dynamic
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2917 nb_syms
= sh
->sh_size
/ sizeof(ElfW(Sym
));
2918 dynsym
= load_data(fd
, sh
->sh_offset
, sh
->sh_size
);
2919 sh1
= &shdr
[sh
->sh_link
];
2920 dynstr
= load_data(fd
, sh1
->sh_offset
, sh1
->sh_size
);
2927 /* compute the real library name */
2928 soname
= tcc_basename(filename
);
2930 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
2931 if (dt
->d_tag
== DT_SONAME
) {
2932 soname
= (char *) dynstr
+ dt
->d_un
.d_val
;
2936 /* if the dll is already loaded, do not load it */
2937 for(i
= 0; i
< s1
->nb_loaded_dlls
; i
++) {
2938 dllref
= s1
->loaded_dlls
[i
];
2939 if (!strcmp(soname
, dllref
->name
)) {
2940 /* but update level if needed */
2941 if (level
< dllref
->level
)
2942 dllref
->level
= level
;
2948 /* add the dll and its level */
2949 dllref
= tcc_mallocz(sizeof(DLLReference
) + strlen(soname
));
2950 dllref
->level
= level
;
2951 strcpy(dllref
->name
, soname
);
2952 dynarray_add((void ***)&s1
->loaded_dlls
, &s1
->nb_loaded_dlls
, dllref
);
2954 /* add dynamic symbols in dynsym_section */
2955 for(i
= 1, sym
= dynsym
+ 1; i
< nb_syms
; i
++, sym
++) {
2956 sym_bind
= ELFW(ST_BIND
)(sym
->st_info
);
2957 if (sym_bind
== STB_LOCAL
)
2959 name
= (char *) dynstr
+ sym
->st_name
;
2960 add_elf_sym(s1
->dynsymtab_section
, sym
->st_value
, sym
->st_size
,
2961 sym
->st_info
, sym
->st_other
, sym
->st_shndx
, name
);
2964 /* load all referenced DLLs */
2965 for(i
= 0, dt
= dynamic
; i
< nb_dts
; i
++, dt
++) {
2968 name
= (char *) dynstr
+ dt
->d_un
.d_val
;
2969 for(j
= 0; j
< s1
->nb_loaded_dlls
; j
++) {
2970 dllref
= s1
->loaded_dlls
[j
];
2971 if (!strcmp(name
, dllref
->name
))
2972 goto already_loaded
;
2974 if (tcc_add_dll(s1
, name
, AFF_REFERENCED_DLL
) < 0) {
2975 tcc_error_noabort("referenced dll '%s' not found", name
);
2992 #define LD_TOK_NAME 256
2993 #define LD_TOK_EOF (-1)
2995 /* return next ld script token */
2996 static int ld_next(TCCState
*s1
, char *name
, int name_size
)
3014 file
->buf_ptr
= parse_comment(file
->buf_ptr
);
3015 ch
= file
->buf_ptr
[0];
3023 /* case 'a' ... 'z': */
3050 /* case 'A' ... 'z': */
3085 if (!((ch
>= 'a' && ch
<= 'z') ||
3086 (ch
>= 'A' && ch
<= 'Z') ||
3087 (ch
>= '0' && ch
<= '9') ||
3088 strchr("/.-_+=$:\\,~", ch
)))
3090 if ((q
- name
) < name_size
- 1) {
3109 static int ld_add_file(TCCState
*s1
, const char filename
[])
3113 ret
= tcc_add_file_internal(s1
, filename
, 0);
3115 ret
= tcc_add_dll(s1
, filename
, 0);
3119 static inline int new_undef_syms(void)
3122 ret
= new_undef_sym
;
3127 static int ld_add_file_list(TCCState
*s1
, const char *cmd
, int as_needed
)
3129 char filename
[1024], libname
[1024];
3130 int t
, group
, nblibs
= 0, ret
= 0;
3133 group
= !strcmp(cmd
, "GROUP");
3136 t
= ld_next(s1
, filename
, sizeof(filename
));
3139 t
= ld_next(s1
, filename
, sizeof(filename
));
3142 if (t
== LD_TOK_EOF
) {
3143 tcc_error_noabort("unexpected end of file");
3145 goto lib_parse_error
;
3146 } else if (t
== ')') {
3148 } else if (t
== '-') {
3149 t
= ld_next(s1
, filename
, sizeof(filename
));
3150 if ((t
!= LD_TOK_NAME
) || (filename
[0] != 'l')) {
3151 tcc_error_noabort("library name expected");
3153 goto lib_parse_error
;
3155 pstrcpy(libname
, sizeof libname
, &filename
[1]);
3156 if (s1
->static_link
) {
3157 snprintf(filename
, sizeof filename
, "lib%s.a", libname
);
3159 snprintf(filename
, sizeof filename
, "lib%s.so", libname
);
3161 } else if (t
!= LD_TOK_NAME
) {
3162 tcc_error_noabort("filename expected");
3164 goto lib_parse_error
;
3166 if (!strcmp(filename
, "AS_NEEDED")) {
3167 ret
= ld_add_file_list(s1
, cmd
, 1);
3169 goto lib_parse_error
;
3171 /* TODO: Implement AS_NEEDED support. Ignore it for now */
3173 ret
= ld_add_file(s1
, filename
);
3175 goto lib_parse_error
;
3177 /* Add the filename *and* the libname to avoid future conversions */
3178 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(filename
));
3179 if (libname
[0] != '\0')
3180 dynarray_add((void ***) &libs
, &nblibs
, tcc_strdup(libname
));
3184 t
= ld_next(s1
, filename
, sizeof(filename
));
3186 t
= ld_next(s1
, filename
, sizeof(filename
));
3189 if (group
&& !as_needed
) {
3190 while (new_undef_syms()) {
3193 for (i
= 0; i
< nblibs
; i
++)
3194 ld_add_file(s1
, libs
[i
]);
3198 dynarray_reset(&libs
, &nblibs
);
3202 /* interpret a subset of GNU ldscripts to handle the dummy libc.so
3204 ST_FUNC
int tcc_load_ldscript(TCCState
*s1
)
3207 char filename
[1024];
3210 ch
= file
->buf_ptr
[0];
3213 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3214 if (t
== LD_TOK_EOF
)
3216 else if (t
!= LD_TOK_NAME
)
3218 if (!strcmp(cmd
, "INPUT") ||
3219 !strcmp(cmd
, "GROUP")) {
3220 ret
= ld_add_file_list(s1
, cmd
, 0);
3223 } else if (!strcmp(cmd
, "OUTPUT_FORMAT") ||
3224 !strcmp(cmd
, "TARGET")) {
3225 /* ignore some commands */
3226 t
= ld_next(s1
, cmd
, sizeof(cmd
));
3230 t
= ld_next(s1
, filename
, sizeof(filename
));
3231 if (t
== LD_TOK_EOF
) {
3232 tcc_error_noabort("unexpected end of file");
3234 } else if (t
== ')') {
3244 #endif /* !TCC_TARGET_PE */