1 /* Read ELF (Executable and Linking Format) object files for GDB.
3 Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
5 Free Software Foundation, Inc.
7 Written by Fred Fish at Cygnus Support.
9 This file is part of GDB.
11 This program is free software; you can redistribute it and/or modify
12 it under the terms of the GNU General Public License as published by
13 the Free Software Foundation; either version 3 of the License, or
14 (at your option) any later version.
16 This program is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 GNU General Public License for more details.
21 You should have received a copy of the GNU General Public License
22 along with this program. If not, see <http://www.gnu.org/licenses/>. */
26 #include "gdb_string.h"
28 #include "elf/common.h"
29 #include "elf/internal.h"
35 #include "stabsread.h"
36 #include "gdb-stabs.h"
37 #include "complaints.h"
40 extern void _initialize_elfread (void);
42 /* The struct elfinfo is available only during ELF symbol table and
43 psymtab reading. It is destroyed at the completion of psymtab-reading.
44 It's local to elf_symfile_read. */
48 asection
*stabsect
; /* Section pointer for .stab section */
49 asection
*stabindexsect
; /* Section pointer for .stab.index section */
50 asection
*mdebugsect
; /* Section pointer for .mdebug section */
53 static void free_elfinfo (void *);
55 /* Locate the segments in ABFD. */
57 static struct symfile_segment_data
*
58 elf_symfile_segments (bfd
*abfd
)
60 Elf_Internal_Phdr
*phdrs
, **segments
;
62 int num_phdrs
, num_segments
, num_sections
, i
;
64 struct symfile_segment_data
*data
;
66 phdrs_size
= bfd_get_elf_phdr_upper_bound (abfd
);
70 phdrs
= alloca (phdrs_size
);
71 num_phdrs
= bfd_get_elf_phdrs (abfd
, phdrs
);
76 segments
= alloca (sizeof (Elf_Internal_Phdr
*) * num_phdrs
);
77 for (i
= 0; i
< num_phdrs
; i
++)
78 if (phdrs
[i
].p_type
== PT_LOAD
)
79 segments
[num_segments
++] = &phdrs
[i
];
81 if (num_segments
== 0)
84 data
= XZALLOC (struct symfile_segment_data
);
85 data
->num_segments
= num_segments
;
86 data
->segment_bases
= XCALLOC (num_segments
, CORE_ADDR
);
87 data
->segment_sizes
= XCALLOC (num_segments
, CORE_ADDR
);
89 for (i
= 0; i
< num_segments
; i
++)
91 data
->segment_bases
[i
] = segments
[i
]->p_vaddr
;
92 data
->segment_sizes
[i
] = segments
[i
]->p_memsz
;
95 num_sections
= bfd_count_sections (abfd
);
96 data
->segment_info
= XCALLOC (num_sections
, int);
98 for (i
= 0, sect
= abfd
->sections
; sect
!= NULL
; i
++, sect
= sect
->next
)
103 if ((bfd_get_section_flags (abfd
, sect
) & SEC_ALLOC
) == 0)
106 vma
= bfd_get_section_vma (abfd
, sect
);
108 for (j
= 0; j
< num_segments
; j
++)
109 if (segments
[j
]->p_memsz
> 0
110 && vma
>= segments
[j
]->p_vaddr
111 && (vma
- segments
[j
]->p_vaddr
) < segments
[j
]->p_memsz
)
113 data
->segment_info
[i
] = j
+ 1;
117 if (bfd_get_section_size (sect
) > 0 && j
== num_segments
)
118 warning (_("Loadable segment \"%s\" outside of ELF segments"),
119 bfd_section_name (abfd
, sect
));
125 /* We are called once per section from elf_symfile_read. We
126 need to examine each section we are passed, check to see
127 if it is something we are interested in processing, and
128 if so, stash away some access information for the section.
130 For now we recognize the dwarf debug information sections and
131 line number sections from matching their section names. The
132 ELF definition is no real help here since it has no direct
133 knowledge of DWARF (by design, so any debugging format can be
136 We also recognize the ".stab" sections used by the Sun compilers
137 released with Solaris 2.
139 FIXME: The section names should not be hardwired strings (what
140 should they be? I don't think most object file formats have enough
141 section flags to specify what kind of debug section it is
145 elf_locate_sections (bfd
*ignore_abfd
, asection
*sectp
, void *eip
)
149 ei
= (struct elfinfo
*) eip
;
150 if (strcmp (sectp
->name
, ".stab") == 0)
152 ei
->stabsect
= sectp
;
154 else if (strcmp (sectp
->name
, ".stab.index") == 0)
156 ei
->stabindexsect
= sectp
;
158 else if (strcmp (sectp
->name
, ".mdebug") == 0)
160 ei
->mdebugsect
= sectp
;
164 static struct minimal_symbol
*
165 record_minimal_symbol (char *name
, CORE_ADDR address
,
166 enum minimal_symbol_type ms_type
,
167 asection
*bfd_section
, struct objfile
*objfile
)
169 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
171 if (ms_type
== mst_text
|| ms_type
== mst_file_text
)
172 address
= gdbarch_smash_text_address (gdbarch
, address
);
174 return prim_record_minimal_symbol_and_info
175 (name
, address
, ms_type
, bfd_section
->index
, bfd_section
, objfile
);
182 elf_symtab_read -- read the symbol table of an ELF file
186 void elf_symtab_read (struct objfile *objfile, int type,
187 long number_of_symbols, asymbol **symbol_table)
191 Given an objfile, a symbol table, and a flag indicating whether the
192 symbol table contains regular, dynamic, or synthetic symbols, add all
193 the global function and data symbols to the minimal symbol table.
195 In stabs-in-ELF, as implemented by Sun, there are some local symbols
196 defined in the ELF symbol table, which can be used to locate
197 the beginnings of sections from each ".o" file that was linked to
198 form the executable objfile. We gather any such info and record it
199 in data structures hung off the objfile's private data.
205 #define ST_SYNTHETIC 2
208 elf_symtab_read (struct objfile
*objfile
, int type
,
209 long number_of_symbols
, asymbol
**symbol_table
)
211 struct gdbarch
*gdbarch
= get_objfile_arch (objfile
);
217 enum minimal_symbol_type ms_type
;
218 /* If sectinfo is nonNULL, it contains section info that should end up
219 filed in the objfile. */
220 struct stab_section_info
*sectinfo
= NULL
;
221 /* If filesym is nonzero, it points to a file symbol, but we haven't
222 seen any section info for it yet. */
223 asymbol
*filesym
= 0;
224 /* Name of filesym, as saved on the objfile_obstack. */
225 char *filesymname
= obsavestring ("", 0, &objfile
->objfile_obstack
);
226 struct dbx_symfile_info
*dbx
= objfile
->deprecated_sym_stab_info
;
227 int stripped
= (bfd_get_symcount (objfile
->obfd
) == 0);
229 for (i
= 0; i
< number_of_symbols
; i
++)
231 sym
= symbol_table
[i
];
232 if (sym
->name
== NULL
|| *sym
->name
== '\0')
234 /* Skip names that don't exist (shouldn't happen), or names
235 that are null strings (may happen). */
239 /* Skip "special" symbols, e.g. ARM mapping symbols. These are
240 symbols which do not correspond to objects in the symbol table,
241 but have some other target-specific meaning. */
242 if (bfd_is_target_special_symbol (objfile
->obfd
, sym
))
244 if (gdbarch_record_special_symbol_p (gdbarch
))
245 gdbarch_record_special_symbol (gdbarch
, objfile
, sym
);
249 offset
= ANOFFSET (objfile
->section_offsets
, sym
->section
->index
);
250 if (type
== ST_DYNAMIC
251 && sym
->section
== &bfd_und_section
252 && (sym
->flags
& BSF_FUNCTION
))
254 struct minimal_symbol
*msym
;
255 bfd
*abfd
= objfile
->obfd
;
258 /* Symbol is a reference to a function defined in
260 If its value is non zero then it is usually the address
261 of the corresponding entry in the procedure linkage table,
262 plus the desired section offset.
263 If its value is zero then the dynamic linker has to resolve
264 the symbol. We are unable to find any meaningful address
265 for this symbol in the executable file, so we skip it. */
266 symaddr
= sym
->value
;
270 /* sym->section is the undefined section. However, we want to
271 record the section where the PLT stub resides with the
272 minimal symbol. Search the section table for the one that
273 covers the stub's address. */
274 for (sect
= abfd
->sections
; sect
!= NULL
; sect
= sect
->next
)
276 if ((bfd_get_section_flags (abfd
, sect
) & SEC_ALLOC
) == 0)
279 if (symaddr
>= bfd_get_section_vma (abfd
, sect
)
280 && symaddr
< bfd_get_section_vma (abfd
, sect
)
281 + bfd_get_section_size (sect
))
287 symaddr
+= ANOFFSET (objfile
->section_offsets
, sect
->index
);
289 msym
= record_minimal_symbol
290 ((char *) sym
->name
, symaddr
, mst_solib_trampoline
, sect
, objfile
);
292 msym
->filename
= filesymname
;
296 /* If it is a nonstripped executable, do not enter dynamic
297 symbols, as the dynamic symbol table is usually a subset
298 of the main symbol table. */
299 if (type
== ST_DYNAMIC
&& !stripped
)
301 if (sym
->flags
& BSF_FILE
)
303 /* STT_FILE debugging symbol that helps stabs-in-elf debugging.
304 Chain any old one onto the objfile; remember new sym. */
305 if (sectinfo
!= NULL
)
307 sectinfo
->next
= dbx
->stab_section_info
;
308 dbx
->stab_section_info
= sectinfo
;
313 obsavestring ((char *) filesym
->name
, strlen (filesym
->name
),
314 &objfile
->objfile_obstack
);
316 else if (sym
->flags
& BSF_SECTION_SYM
)
318 else if (sym
->flags
& (BSF_GLOBAL
| BSF_LOCAL
| BSF_WEAK
))
320 struct minimal_symbol
*msym
;
322 /* Select global/local/weak symbols. Note that bfd puts abs
323 symbols in their own section, so all symbols we are
324 interested in will have a section. */
325 /* Bfd symbols are section relative. */
326 symaddr
= sym
->value
+ sym
->section
->vma
;
327 /* Relocate all non-absolute and non-TLS symbols by the
329 if (sym
->section
!= &bfd_abs_section
330 && !(sym
->section
->flags
& SEC_THREAD_LOCAL
))
334 /* For non-absolute symbols, use the type of the section
335 they are relative to, to intuit text/data. Bfd provides
336 no way of figuring this out for absolute symbols. */
337 if (sym
->section
== &bfd_abs_section
)
339 /* This is a hack to get the minimal symbol type
340 right for Irix 5, which has absolute addresses
341 with special section indices for dynamic symbols.
343 NOTE: uweigand-20071112: Synthetic symbols do not
344 have an ELF-private part, so do not touch those. */
345 unsigned int shndx
= type
== ST_SYNTHETIC
? 0 :
346 ((elf_symbol_type
*) sym
)->internal_elf_sym
.st_shndx
;
356 case SHN_MIPS_ACOMMON
:
363 /* If it is an Irix dynamic symbol, skip section name
364 symbols, relocate all others by section offset. */
365 if (ms_type
!= mst_abs
)
367 if (sym
->name
[0] == '.')
372 else if (sym
->section
->flags
& SEC_CODE
)
374 if (sym
->flags
& (BSF_GLOBAL
| BSF_WEAK
))
378 else if ((sym
->name
[0] == '.' && sym
->name
[1] == 'L')
379 || ((sym
->flags
& BSF_LOCAL
)
380 && sym
->name
[0] == '$'
381 && sym
->name
[1] == 'L'))
382 /* Looks like a compiler-generated label. Skip
383 it. The assembler should be skipping these (to
384 keep executables small), but apparently with
385 gcc on the (deleted) delta m88k SVR4, it loses.
386 So to have us check too should be harmless (but
387 I encourage people to fix this in the assembler
388 instead of adding checks here). */
392 ms_type
= mst_file_text
;
395 else if (sym
->section
->flags
& SEC_ALLOC
)
397 if (sym
->flags
& (BSF_GLOBAL
| BSF_WEAK
))
399 if (sym
->section
->flags
& SEC_LOAD
)
408 else if (sym
->flags
& BSF_LOCAL
)
410 /* Named Local variable in a Data section.
411 Check its name for stabs-in-elf. */
412 int special_local_sect
;
413 if (strcmp ("Bbss.bss", sym
->name
) == 0)
414 special_local_sect
= SECT_OFF_BSS (objfile
);
415 else if (strcmp ("Ddata.data", sym
->name
) == 0)
416 special_local_sect
= SECT_OFF_DATA (objfile
);
417 else if (strcmp ("Drodata.rodata", sym
->name
) == 0)
418 special_local_sect
= SECT_OFF_RODATA (objfile
);
420 special_local_sect
= -1;
421 if (special_local_sect
>= 0)
423 /* Found a special local symbol. Allocate a
424 sectinfo, if needed, and fill it in. */
425 if (sectinfo
== NULL
)
430 max_index
= SECT_OFF_BSS (objfile
);
431 if (objfile
->sect_index_data
> max_index
)
432 max_index
= objfile
->sect_index_data
;
433 if (objfile
->sect_index_rodata
> max_index
)
434 max_index
= objfile
->sect_index_rodata
;
436 /* max_index is the largest index we'll
437 use into this array, so we must
438 allocate max_index+1 elements for it.
439 However, 'struct stab_section_info'
440 already includes one element, so we
441 need to allocate max_index aadditional
443 size
= (sizeof (struct stab_section_info
)
444 + (sizeof (CORE_ADDR
)
446 sectinfo
= (struct stab_section_info
*)
448 memset (sectinfo
, 0, size
);
449 sectinfo
->num_sections
= max_index
;
452 complaint (&symfile_complaints
,
453 _("elf/stab section information %s without a preceding file symbol"),
459 (char *) filesym
->name
;
462 if (sectinfo
->sections
[special_local_sect
] != 0)
463 complaint (&symfile_complaints
,
464 _("duplicated elf/stab section information for %s"),
466 /* BFD symbols are section relative. */
467 symaddr
= sym
->value
+ sym
->section
->vma
;
468 /* Relocate non-absolute symbols by the
470 if (sym
->section
!= &bfd_abs_section
)
472 sectinfo
->sections
[special_local_sect
] = symaddr
;
473 /* The special local symbols don't go in the
474 minimal symbol table, so ignore this one. */
477 /* Not a special stabs-in-elf symbol, do regular
478 symbol processing. */
479 if (sym
->section
->flags
& SEC_LOAD
)
481 ms_type
= mst_file_data
;
485 ms_type
= mst_file_bss
;
490 ms_type
= mst_unknown
;
495 /* FIXME: Solaris2 shared libraries include lots of
496 odd "absolute" and "undefined" symbols, that play
497 hob with actions like finding what function the PC
498 is in. Ignore them if they aren't text, data, or bss. */
499 /* ms_type = mst_unknown; */
500 continue; /* Skip this symbol. */
502 msym
= record_minimal_symbol
503 ((char *) sym
->name
, symaddr
,
504 ms_type
, sym
->section
, objfile
);
508 /* Pass symbol size field in via BFD. FIXME!!! */
509 elf_symbol_type
*elf_sym
;
511 /* NOTE: uweigand-20071112: A synthetic symbol does not have an
512 ELF-private part. However, in some cases (e.g. synthetic
513 'dot' symbols on ppc64) the udata.p entry is set to point back
514 to the original ELF symbol it was derived from. Get the size
516 if (type
!= ST_SYNTHETIC
)
517 elf_sym
= (elf_symbol_type
*) sym
;
519 elf_sym
= (elf_symbol_type
*) sym
->udata
.p
;
522 MSYMBOL_SIZE(msym
) = elf_sym
->internal_elf_sym
.st_size
;
525 msym
->filename
= filesymname
;
526 gdbarch_elf_make_msymbol_special (gdbarch
, sym
, msym
);
528 /* For @plt symbols, also record a trampoline to the
529 destination symbol. The @plt symbol will be used in
530 disassembly, and the trampoline will be used when we are
531 trying to find the target. */
532 if (msym
&& ms_type
== mst_text
&& type
== ST_SYNTHETIC
)
534 int len
= strlen (sym
->name
);
536 if (len
> 4 && strcmp (sym
->name
+ len
- 4, "@plt") == 0)
538 char *base_name
= xmalloc (len
- 4 + 1);
539 struct minimal_symbol
*mtramp
;
541 memcpy (base_name
, sym
->name
, len
- 4);
542 base_name
[len
- 4] = '\0';
543 mtramp
= record_minimal_symbol (base_name
, symaddr
,
544 mst_solib_trampoline
,
545 sym
->section
, objfile
);
549 MSYMBOL_SIZE (mtramp
) = MSYMBOL_SIZE (msym
);
550 mtramp
->filename
= filesymname
;
551 gdbarch_elf_make_msymbol_special (gdbarch
, sym
, mtramp
);
559 /* Scan and build partial symbols for a symbol file.
560 We have been initialized by a call to elf_symfile_init, which
561 currently does nothing.
563 SECTION_OFFSETS is a set of offsets to apply to relocate the symbols
564 in each section. We simplify it down to a single offset for all
567 MAINLINE is true if we are reading the main symbol
568 table (as opposed to a shared lib or dynamically loaded file).
570 This function only does the minimum work necessary for letting the
571 user "name" things symbolically; it does not read the entire symtab.
572 Instead, it reads the external and static symbols and puts them in partial
573 symbol tables. When more extensive information is requested of a
574 file, the corresponding partial symbol table is mutated into a full
575 fledged symbol table by going back and reading the symbols
578 We look for sections with specific names, to tell us what debug
579 format to look for: FIXME!!!
581 elfstab_build_psymtabs() handles STABS symbols;
582 mdebug_build_psymtabs() handles ECOFF debugging information.
584 Note that ELF files have a "minimal" symbol table, which looks a lot
585 like a COFF symbol table, but has only the minimal information necessary
586 for linking. We process this also, and use the information to
587 build gdb's minimal symbol table. This gives us some minimal debugging
588 capability even for files compiled without -g. */
591 elf_symfile_read (struct objfile
*objfile
, int mainline
)
593 bfd
*abfd
= objfile
->obfd
;
595 struct cleanup
*back_to
;
597 long symcount
= 0, dynsymcount
= 0, synthcount
, storage_needed
;
598 asymbol
**symbol_table
= NULL
, **dyn_symbol_table
= NULL
;
601 init_minimal_symbol_collection ();
602 back_to
= make_cleanup_discard_minimal_symbols ();
604 memset ((char *) &ei
, 0, sizeof (ei
));
606 /* Allocate struct to keep track of the symfile */
607 objfile
->deprecated_sym_stab_info
= (struct dbx_symfile_info
*)
608 xmalloc (sizeof (struct dbx_symfile_info
));
609 memset ((char *) objfile
->deprecated_sym_stab_info
, 0, sizeof (struct dbx_symfile_info
));
610 make_cleanup (free_elfinfo
, (void *) objfile
);
612 /* Process the normal ELF symbol table first. This may write some
613 chain of info into the dbx_symfile_info in objfile->deprecated_sym_stab_info,
614 which can later be used by elfstab_offset_sections. */
616 storage_needed
= bfd_get_symtab_upper_bound (objfile
->obfd
);
617 if (storage_needed
< 0)
618 error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile
->obfd
),
619 bfd_errmsg (bfd_get_error ()));
621 if (storage_needed
> 0)
623 symbol_table
= (asymbol
**) xmalloc (storage_needed
);
624 make_cleanup (xfree
, symbol_table
);
625 symcount
= bfd_canonicalize_symtab (objfile
->obfd
, symbol_table
);
628 error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile
->obfd
),
629 bfd_errmsg (bfd_get_error ()));
631 elf_symtab_read (objfile
, ST_REGULAR
, symcount
, symbol_table
);
634 /* Add the dynamic symbols. */
636 storage_needed
= bfd_get_dynamic_symtab_upper_bound (objfile
->obfd
);
638 if (storage_needed
> 0)
640 dyn_symbol_table
= (asymbol
**) xmalloc (storage_needed
);
641 make_cleanup (xfree
, dyn_symbol_table
);
642 dynsymcount
= bfd_canonicalize_dynamic_symtab (objfile
->obfd
,
646 error (_("Can't read symbols from %s: %s"), bfd_get_filename (objfile
->obfd
),
647 bfd_errmsg (bfd_get_error ()));
649 elf_symtab_read (objfile
, ST_DYNAMIC
, dynsymcount
, dyn_symbol_table
);
652 /* Add synthetic symbols - for instance, names for any PLT entries. */
654 synthcount
= bfd_get_synthetic_symtab (abfd
, symcount
, symbol_table
,
655 dynsymcount
, dyn_symbol_table
,
659 asymbol
**synth_symbol_table
;
662 make_cleanup (xfree
, synthsyms
);
663 synth_symbol_table
= xmalloc (sizeof (asymbol
*) * synthcount
);
664 for (i
= 0; i
< synthcount
; i
++)
665 synth_symbol_table
[i
] = synthsyms
+ i
;
666 make_cleanup (xfree
, synth_symbol_table
);
667 elf_symtab_read (objfile
, ST_SYNTHETIC
, synthcount
, synth_symbol_table
);
670 /* Install any minimal symbols that have been collected as the current
671 minimal symbols for this objfile. The debug readers below this point
672 should not generate new minimal symbols; if they do it's their
673 responsibility to install them. "mdebug" appears to be the only one
674 which will do this. */
676 install_minimal_symbols (objfile
);
677 do_cleanups (back_to
);
679 /* Now process debugging information, which is contained in
680 special ELF sections. */
682 /* If we are reinitializing, or if we have never loaded syms yet,
683 set table to empty. MAINLINE is cleared so that *_read_psymtab
684 functions do not all also re-initialize the psymbol table. */
687 init_psymbol_list (objfile
, 0);
691 /* We first have to find them... */
692 bfd_map_over_sections (abfd
, elf_locate_sections
, (void *) & ei
);
694 /* ELF debugging information is inserted into the psymtab in the
695 order of least informative first - most informative last. Since
696 the psymtab table is searched `most recent insertion first' this
697 increases the probability that more detailed debug information
698 for a section is found.
700 For instance, an object file might contain both .mdebug (XCOFF)
701 and .debug_info (DWARF2) sections then .mdebug is inserted first
702 (searched last) and DWARF2 is inserted last (searched first). If
703 we don't do this then the XCOFF info is found first - for code in
704 an included file XCOFF info is useless. */
708 const struct ecoff_debug_swap
*swap
;
710 /* .mdebug section, presumably holding ECOFF debugging
712 swap
= get_elf_backend_data (abfd
)->elf_backend_ecoff_debug_swap
;
714 elfmdebug_build_psymtabs (objfile
, swap
, ei
.mdebugsect
);
720 /* Stab sections have an associated string table that looks like
721 a separate section. */
722 str_sect
= bfd_get_section_by_name (abfd
, ".stabstr");
724 /* FIXME should probably warn about a stab section without a stabstr. */
726 elfstab_build_psymtabs (objfile
,
730 bfd_section_size (abfd
, str_sect
));
732 if (dwarf2_has_info (objfile
))
734 /* DWARF 2 sections */
735 dwarf2_build_psymtabs (objfile
, mainline
);
738 /* FIXME: kettenis/20030504: This still needs to be integrated with
739 dwarf2read.c in a better way. */
740 dwarf2_build_frame_info (objfile
);
743 /* This cleans up the objfile's deprecated_sym_stab_info pointer, and
744 the chain of stab_section_info's, that might be dangling from
748 free_elfinfo (void *objp
)
750 struct objfile
*objfile
= (struct objfile
*) objp
;
751 struct dbx_symfile_info
*dbxinfo
= objfile
->deprecated_sym_stab_info
;
752 struct stab_section_info
*ssi
, *nssi
;
754 ssi
= dbxinfo
->stab_section_info
;
762 dbxinfo
->stab_section_info
= 0; /* Just say No mo info about this. */
766 /* Initialize anything that needs initializing when a completely new symbol
767 file is specified (not just adding some symbols from another file, e.g. a
770 We reinitialize buildsym, since we may be reading stabs from an ELF file. */
773 elf_new_init (struct objfile
*ignore
)
775 stabsread_new_init ();
776 buildsym_new_init ();
779 /* Perform any local cleanups required when we are done with a particular
780 objfile. I.E, we are in the process of discarding all symbol information
781 for an objfile, freeing up all memory held for it, and unlinking the
782 objfile struct from the global list of known objfiles. */
785 elf_symfile_finish (struct objfile
*objfile
)
787 if (objfile
->deprecated_sym_stab_info
!= NULL
)
789 xfree (objfile
->deprecated_sym_stab_info
);
792 dwarf2_free_objfile (objfile
);
795 /* ELF specific initialization routine for reading symbols.
797 It is passed a pointer to a struct sym_fns which contains, among other
798 things, the BFD for the file whose symbols are being read, and a slot for
799 a pointer to "private data" which we can fill with goodies.
801 For now at least, we have nothing in particular to do, so this function is
805 elf_symfile_init (struct objfile
*objfile
)
807 /* ELF objects may be reordered, so set OBJF_REORDERED. If we
808 find this causes a significant slowdown in gdb then we could
809 set it in the debug symbol readers only when necessary. */
810 objfile
->flags
|= OBJF_REORDERED
;
813 /* When handling an ELF file that contains Sun STABS debug info,
814 some of the debug info is relative to the particular chunk of the
815 section that was generated in its individual .o file. E.g.
816 offsets to static variables are relative to the start of the data
817 segment *for that module before linking*. This information is
818 painfully squirreled away in the ELF symbol table as local symbols
819 with wierd names. Go get 'em when needed. */
822 elfstab_offset_sections (struct objfile
*objfile
, struct partial_symtab
*pst
)
824 char *filename
= pst
->filename
;
825 struct dbx_symfile_info
*dbx
= objfile
->deprecated_sym_stab_info
;
826 struct stab_section_info
*maybe
= dbx
->stab_section_info
;
827 struct stab_section_info
*questionable
= 0;
831 /* The ELF symbol info doesn't include path names, so strip the path
832 (if any) from the psymtab filename. */
833 while (0 != (p
= strchr (filename
, '/')))
836 /* FIXME: This linear search could speed up significantly
837 if it was chained in the right order to match how we search it,
838 and if we unchained when we found a match. */
839 for (; maybe
; maybe
= maybe
->next
)
841 if (filename
[0] == maybe
->filename
[0]
842 && strcmp (filename
, maybe
->filename
) == 0)
844 /* We found a match. But there might be several source files
845 (from different directories) with the same name. */
846 if (0 == maybe
->found
)
848 questionable
= maybe
; /* Might use it later. */
852 if (maybe
== 0 && questionable
!= 0)
854 complaint (&symfile_complaints
,
855 _("elf/stab section information questionable for %s"), filename
);
856 maybe
= questionable
;
861 /* Found it! Allocate a new psymtab struct, and fill it in. */
863 pst
->section_offsets
= (struct section_offsets
*)
864 obstack_alloc (&objfile
->objfile_obstack
,
865 SIZEOF_N_SECTION_OFFSETS (objfile
->num_sections
));
866 for (i
= 0; i
< maybe
->num_sections
; i
++)
867 (pst
->section_offsets
)->offsets
[i
] = maybe
->sections
[i
];
871 /* We were unable to find any offsets for this file. Complain. */
872 if (dbx
->stab_section_info
) /* If there *is* any info, */
873 complaint (&symfile_complaints
,
874 _("elf/stab section information missing for %s"), filename
);
877 /* Register that we are able to handle ELF object file formats. */
879 static struct sym_fns elf_sym_fns
=
881 bfd_target_elf_flavour
,
882 elf_new_init
, /* sym_new_init: init anything gbl to entire symtab */
883 elf_symfile_init
, /* sym_init: read initial info, setup for sym_read() */
884 elf_symfile_read
, /* sym_read: read a symbol file into symtab */
885 elf_symfile_finish
, /* sym_finish: finished with file, cleanup */
886 default_symfile_offsets
, /* sym_offsets: Translate ext. to int. relocation */
887 elf_symfile_segments
, /* sym_segments: Get segment information from
889 NULL
, /* sym_read_linetable */
890 NULL
/* next: pointer to next struct sym_fns */
894 _initialize_elfread (void)
896 add_symtab_fns (&elf_sym_fns
);