1 /* Handle SVR4 shared libraries for GDB, the GNU Debugger.
3 Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000,
4 2001, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
25 #include "elf/external.h"
26 #include "elf/common.h"
37 #include "gdb_assert.h"
41 #include "solib-svr4.h"
43 #include "bfd-target.h"
47 static struct link_map_offsets
*svr4_fetch_link_map_offsets (void);
48 static int svr4_have_link_map_offsets (void);
50 /* This hook is set to a function that provides native link map
51 offsets if the code in solib-legacy.c is linked in. */
52 struct link_map_offsets
*(*legacy_svr4_fetch_link_map_offsets_hook
) (void);
54 /* Link map info to include in an allocated so_list entry */
58 /* Pointer to copy of link map from inferior. The type is char *
59 rather than void *, so that we may use byte offsets to find the
60 various fields without the need for a cast. */
63 /* Amount by which addresses in the binary should be relocated to
64 match the inferior. This could most often be taken directly
65 from lm, but when prelinking is involved and the prelink base
66 address changes, we may need a different offset, we want to
67 warn about the difference and compute it only once. */
71 /* On SVR4 systems, a list of symbols in the dynamic linker where
72 GDB can try to place a breakpoint to monitor shared library
75 If none of these symbols are found, or other errors occur, then
76 SVR4 systems will fall back to using a symbol as the "startup
77 mapping complete" breakpoint address. */
79 static char *solib_break_names
[] =
90 #define BKPT_AT_SYMBOL 1
92 #if defined (BKPT_AT_SYMBOL)
93 static char *bkpt_names
[] =
95 #ifdef SOLIB_BKPT_NAME
96 SOLIB_BKPT_NAME
, /* Prefer configured name if it exists. */
105 static char *main_name_list
[] =
111 /* link map access functions */
114 LM_ADDR_FROM_LINK_MAP (struct so_list
*so
)
116 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
118 return extract_typed_address (so
->lm_info
->lm
+ lmo
->l_addr_offset
,
119 builtin_type_void_data_ptr
);
123 HAS_LM_DYNAMIC_FROM_LINK_MAP ()
125 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
127 return lmo
->l_ld_offset
>= 0;
131 LM_DYNAMIC_FROM_LINK_MAP (struct so_list
*so
)
133 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
135 return extract_typed_address (so
->lm_info
->lm
+ lmo
->l_ld_offset
,
136 builtin_type_void_data_ptr
);
140 LM_ADDR_CHECK (struct so_list
*so
, bfd
*abfd
)
142 if (so
->lm_info
->l_addr
== (CORE_ADDR
)-1)
144 struct bfd_section
*dyninfo_sect
;
145 CORE_ADDR l_addr
, l_dynaddr
, dynaddr
, align
= 0x1000;
147 l_addr
= LM_ADDR_FROM_LINK_MAP (so
);
149 if (! abfd
|| ! HAS_LM_DYNAMIC_FROM_LINK_MAP ())
152 l_dynaddr
= LM_DYNAMIC_FROM_LINK_MAP (so
);
154 dyninfo_sect
= bfd_get_section_by_name (abfd
, ".dynamic");
155 if (dyninfo_sect
== NULL
)
158 dynaddr
= bfd_section_vma (abfd
, dyninfo_sect
);
160 if (dynaddr
+ l_addr
!= l_dynaddr
)
162 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
)
164 Elf_Internal_Ehdr
*ehdr
= elf_tdata (abfd
)->elf_header
;
165 Elf_Internal_Phdr
*phdr
= elf_tdata (abfd
)->phdr
;
170 for (i
= 0; i
< ehdr
->e_phnum
; i
++)
171 if (phdr
[i
].p_type
== PT_LOAD
&& phdr
[i
].p_align
> align
)
172 align
= phdr
[i
].p_align
;
175 /* Turn it into a mask. */
178 /* If the changes match the alignment requirements, we
179 assume we're using a core file that was generated by the
180 same binary, just prelinked with a different base offset.
181 If it doesn't match, we may have a different binary, the
182 same binary with the dynamic table loaded at an unrelated
183 location, or anything, really. To avoid regressions,
184 don't adjust the base offset in the latter case, although
185 odds are that, if things really changed, debugging won't
187 if ((l_addr
& align
) == 0 && ((dynaddr
- l_dynaddr
) & align
) == 0)
189 l_addr
= l_dynaddr
- dynaddr
;
191 warning (_(".dynamic section for \"%s\" "
192 "is not at the expected address"), so
->so_name
);
193 warning (_("difference appears to be caused by prelink, "
194 "adjusting expectations"));
197 warning (_(".dynamic section for \"%s\" "
198 "is not at the expected address "
199 "(wrong library or version mismatch?)"), so
->so_name
);
203 so
->lm_info
->l_addr
= l_addr
;
206 return so
->lm_info
->l_addr
;
210 LM_NEXT (struct so_list
*so
)
212 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
214 return extract_typed_address (so
->lm_info
->lm
+ lmo
->l_next_offset
,
215 builtin_type_void_data_ptr
);
219 LM_NAME (struct so_list
*so
)
221 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
223 return extract_typed_address (so
->lm_info
->lm
+ lmo
->l_name_offset
,
224 builtin_type_void_data_ptr
);
228 IGNORE_FIRST_LINK_MAP_ENTRY (struct so_list
*so
)
230 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
232 /* Assume that everything is a library if the dynamic loader was loaded
233 late by a static executable. */
234 if (bfd_get_section_by_name (exec_bfd
, ".dynamic") == NULL
)
237 return extract_typed_address (so
->lm_info
->lm
+ lmo
->l_prev_offset
,
238 builtin_type_void_data_ptr
) == 0;
241 static CORE_ADDR debug_base
; /* Base of dynamic linker structures */
243 /* Validity flag for debug_loader_offset. */
244 static int debug_loader_offset_p
;
246 /* Load address for the dynamic linker, inferred. */
247 static CORE_ADDR debug_loader_offset
;
249 /* Name of the dynamic linker, valid if debug_loader_offset_p. */
250 static char *debug_loader_name
;
252 /* Local function prototypes */
254 static int match_main (char *);
256 static CORE_ADDR
bfd_lookup_symbol (bfd
*, char *);
262 bfd_lookup_symbol -- lookup the value for a specific symbol
266 CORE_ADDR bfd_lookup_symbol (bfd *abfd, char *symname)
270 An expensive way to lookup the value of a single symbol for
271 bfd's that are only temporary anyway. This is used by the
272 shared library support to find the address of the debugger
273 notification routine in the shared library.
275 The returned symbol may be in a code or data section; functions
276 will normally be in a code section, but may be in a data section
277 if this architecture uses function descriptors.
279 Note that 0 is specifically allowed as an error return (no
284 bfd_lookup_symbol (bfd
*abfd
, char *symname
)
288 asymbol
**symbol_table
;
289 unsigned int number_of_symbols
;
291 struct cleanup
*back_to
;
292 CORE_ADDR symaddr
= 0;
294 storage_needed
= bfd_get_symtab_upper_bound (abfd
);
296 if (storage_needed
> 0)
298 symbol_table
= (asymbol
**) xmalloc (storage_needed
);
299 back_to
= make_cleanup (xfree
, symbol_table
);
300 number_of_symbols
= bfd_canonicalize_symtab (abfd
, symbol_table
);
302 for (i
= 0; i
< number_of_symbols
; i
++)
304 sym
= *symbol_table
++;
305 if (strcmp (sym
->name
, symname
) == 0
306 && (sym
->section
->flags
& (SEC_CODE
| SEC_DATA
)) != 0)
308 /* BFD symbols are section relative. */
309 symaddr
= sym
->value
+ sym
->section
->vma
;
313 do_cleanups (back_to
);
319 /* On FreeBSD, the dynamic linker is stripped by default. So we'll
320 have to check the dynamic string table too. */
322 storage_needed
= bfd_get_dynamic_symtab_upper_bound (abfd
);
324 if (storage_needed
> 0)
326 symbol_table
= (asymbol
**) xmalloc (storage_needed
);
327 back_to
= make_cleanup (xfree
, symbol_table
);
328 number_of_symbols
= bfd_canonicalize_dynamic_symtab (abfd
, symbol_table
);
330 for (i
= 0; i
< number_of_symbols
; i
++)
332 sym
= *symbol_table
++;
334 if (strcmp (sym
->name
, symname
) == 0
335 && (sym
->section
->flags
& (SEC_CODE
| SEC_DATA
)) != 0)
337 /* BFD symbols are section relative. */
338 symaddr
= sym
->value
+ sym
->section
->vma
;
342 do_cleanups (back_to
);
348 /* Scan for DYNTAG in .dynamic section of ABFD. If DYNTAG is found 1 is
349 returned and the corresponding PTR is set. */
352 scan_dyntag (int dyntag
, bfd
*abfd
, CORE_ADDR
*ptr
)
354 int arch_size
, step
, sect_size
;
356 CORE_ADDR dyn_ptr
, dyn_addr
;
357 gdb_byte
*bufend
, *buf
;
358 Elf32_External_Dyn
*x_dynp_32
;
359 Elf64_External_Dyn
*x_dynp_64
;
360 struct bfd_section
*sect
;
364 arch_size
= bfd_get_arch_size (abfd
);
368 /* Find the start address of the .dynamic section. */
369 sect
= bfd_get_section_by_name (abfd
, ".dynamic");
372 dyn_addr
= bfd_section_vma (abfd
, sect
);
374 /* Read in .dynamic section, silently ignore errors. */
375 sect_size
= bfd_section_size (abfd
, sect
);
376 buf
= alloca (sect_size
);
377 if (target_read_memory (dyn_addr
, buf
, sect_size
))
379 /* If target_read_memory fails, try reading the BFD file. */
380 if (!bfd_get_section_contents (abfd
, sect
,
385 /* Iterate over BUF and scan for DYNTAG. If found, set PTR and return. */
386 step
= (arch_size
== 32) ? sizeof (Elf32_External_Dyn
)
387 : sizeof (Elf64_External_Dyn
);
388 for (bufend
= buf
+ sect_size
;
394 x_dynp_32
= (Elf32_External_Dyn
*) buf
;
395 dyn_tag
= bfd_h_get_32 (abfd
, (bfd_byte
*) x_dynp_32
->d_tag
);
396 dyn_ptr
= bfd_h_get_32 (abfd
, (bfd_byte
*) x_dynp_32
->d_un
.d_ptr
);
400 x_dynp_64
= (Elf64_External_Dyn
*) buf
;
401 dyn_tag
= bfd_h_get_64 (abfd
, (bfd_byte
*) x_dynp_64
->d_tag
);
402 dyn_ptr
= bfd_h_get_64 (abfd
, (bfd_byte
*) x_dynp_64
->d_un
.d_ptr
);
404 if (dyn_tag
== DT_NULL
)
406 if (dyn_tag
== dyntag
)
422 elf_locate_base -- locate the base address of dynamic linker structs
423 for SVR4 elf targets.
427 CORE_ADDR elf_locate_base (void)
431 For SVR4 elf targets the address of the dynamic linker's runtime
432 structure is contained within the dynamic info section in the
433 executable file. The dynamic section is also mapped into the
434 inferior address space. Because the runtime loader fills in the
435 real address before starting the inferior, we have to read in the
436 dynamic info section from the inferior address space.
437 If there are any errors while trying to find the address, we
438 silently return 0, otherwise the found address is returned.
443 elf_locate_base (void)
445 struct minimal_symbol
*msymbol
;
449 if (scan_dyntag (DT_DEBUG
, exec_bfd
, &dyn_ptr
))
452 /* Find DT_MIPS_RLD_MAP. */
453 if (scan_dyntag (DT_MIPS_RLD_MAP
, exec_bfd
, &dyn_ptr
))
456 int pbuf_size
= TYPE_LENGTH (builtin_type_void_data_ptr
);
457 pbuf
= alloca (pbuf_size
);
458 /* DT_MIPS_RLD_MAP contains a pointer to the address
459 of the dynamic link structure. */
460 if (target_read_memory (dyn_ptr
, pbuf
, pbuf_size
))
462 return extract_typed_address (pbuf
, builtin_type_void_data_ptr
);
465 /* This may be a static executable. Look for the symbol
466 conventionally named _r_debug, as a last resort. */
467 msymbol
= lookup_minimal_symbol ("_r_debug", NULL
, symfile_objfile
);
469 return SYMBOL_VALUE_ADDRESS (msymbol
);
471 /* DT_DEBUG entry not found. */
479 locate_base -- locate the base address of dynamic linker structs
483 CORE_ADDR locate_base (void)
487 For both the SunOS and SVR4 shared library implementations, if the
488 inferior executable has been linked dynamically, there is a single
489 address somewhere in the inferior's data space which is the key to
490 locating all of the dynamic linker's runtime structures. This
491 address is the value of the debug base symbol. The job of this
492 function is to find and return that address, or to return 0 if there
493 is no such address (the executable is statically linked for example).
495 For SunOS, the job is almost trivial, since the dynamic linker and
496 all of it's structures are statically linked to the executable at
497 link time. Thus the symbol for the address we are looking for has
498 already been added to the minimal symbol table for the executable's
499 objfile at the time the symbol file's symbols were read, and all we
500 have to do is look it up there. Note that we explicitly do NOT want
501 to find the copies in the shared library.
503 The SVR4 version is a bit more complicated because the address
504 is contained somewhere in the dynamic info section. We have to go
505 to a lot more work to discover the address of the debug base symbol.
506 Because of this complexity, we cache the value we find and return that
507 value on subsequent invocations. Note there is no copy in the
508 executable symbol tables.
515 /* Check to see if we have a currently valid address, and if so, avoid
516 doing all this work again and just return the cached address. If
517 we have no cached address, try to locate it in the dynamic info
518 section for ELF executables. There's no point in doing any of this
519 though if we don't have some link map offsets to work with. */
521 if (debug_base
== 0 && svr4_have_link_map_offsets ())
524 && bfd_get_flavour (exec_bfd
) == bfd_target_elf_flavour
)
525 debug_base
= elf_locate_base ();
530 /* Find the first element in the inferior's dynamic link map, and
531 return its address in the inferior.
533 FIXME: Perhaps we should validate the info somehow, perhaps by
534 checking r_version for a known version number, or r_state for
538 solib_svr4_r_map (void)
540 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
542 return read_memory_typed_address (debug_base
+ lmo
->r_map_offset
,
543 builtin_type_void_data_ptr
);
546 /* Find the link map for the dynamic linker (if it is not in the
547 normal list of loaded shared objects). */
550 solib_svr4_r_ldsomap (void)
552 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
555 /* Check version, and return zero if `struct r_debug' doesn't have
556 the r_ldsomap member. */
557 version
= read_memory_unsigned_integer (debug_base
+ lmo
->r_version_offset
,
558 lmo
->r_version_size
);
559 if (version
< 2 || lmo
->r_ldsomap_offset
== -1)
562 return read_memory_typed_address (debug_base
+ lmo
->r_ldsomap_offset
,
563 builtin_type_void_data_ptr
);
570 open_symbol_file_object
574 void open_symbol_file_object (void *from_tty)
578 If no open symbol file, attempt to locate and open the main symbol
579 file. On SVR4 systems, this is the first link map entry. If its
580 name is here, we can open it. Useful when attaching to a process
581 without first loading its symbol file.
583 If FROM_TTYP dereferences to a non-zero integer, allow messages to
584 be printed. This parameter is a pointer rather than an int because
585 open_symbol_file_object() is called via catch_errors() and
586 catch_errors() requires a pointer argument. */
589 open_symbol_file_object (void *from_ttyp
)
591 CORE_ADDR lm
, l_name
;
594 int from_tty
= *(int *)from_ttyp
;
595 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
596 int l_name_size
= TYPE_LENGTH (builtin_type_void_data_ptr
);
597 gdb_byte
*l_name_buf
= xmalloc (l_name_size
);
598 struct cleanup
*cleanups
= make_cleanup (xfree
, l_name_buf
);
601 if (!query ("Attempt to reload symbols from process? "))
604 if ((debug_base
= locate_base ()) == 0)
605 return 0; /* failed somehow... */
607 /* First link map member should be the executable. */
608 lm
= solib_svr4_r_map ();
610 return 0; /* failed somehow... */
612 /* Read address of name from target memory to GDB. */
613 read_memory (lm
+ lmo
->l_name_offset
, l_name_buf
, l_name_size
);
615 /* Convert the address to host format. */
616 l_name
= extract_typed_address (l_name_buf
, builtin_type_void_data_ptr
);
618 /* Free l_name_buf. */
619 do_cleanups (cleanups
);
622 return 0; /* No filename. */
624 /* Now fetch the filename from target memory. */
625 target_read_string (l_name
, &filename
, SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
629 warning (_("failed to read exec filename from attached file: %s"),
630 safe_strerror (errcode
));
634 make_cleanup (xfree
, filename
);
635 /* Have a pathname: read the symbol file. */
636 symbol_file_add_main (filename
, from_tty
);
641 /* If no shared library information is available from the dynamic
642 linker, build a fallback list from other sources. */
644 static struct so_list
*
645 svr4_default_sos (void)
647 struct so_list
*head
= NULL
;
648 struct so_list
**link_ptr
= &head
;
650 if (debug_loader_offset_p
)
652 struct so_list
*new = XZALLOC (struct so_list
);
654 new->lm_info
= xmalloc (sizeof (struct lm_info
));
656 /* Nothing will ever check the cached copy of the link
657 map if we set l_addr. */
658 new->lm_info
->l_addr
= debug_loader_offset
;
659 new->lm_info
->lm
= NULL
;
661 strncpy (new->so_name
, debug_loader_name
, SO_NAME_MAX_PATH_SIZE
- 1);
662 new->so_name
[SO_NAME_MAX_PATH_SIZE
- 1] = '\0';
663 strcpy (new->so_original_name
, new->so_name
);
666 link_ptr
= &new->next
;
674 current_sos -- build a list of currently loaded shared objects
678 struct so_list *current_sos ()
682 Build a list of `struct so_list' objects describing the shared
683 objects currently loaded in the inferior. This list does not
684 include an entry for the main executable file.
686 Note that we only gather information directly available from the
687 inferior --- we don't examine any of the shared library files
688 themselves. The declaration of `struct so_list' says which fields
689 we provide values for. */
691 static struct so_list
*
692 svr4_current_sos (void)
695 struct so_list
*head
= 0;
696 struct so_list
**link_ptr
= &head
;
697 CORE_ADDR ldsomap
= 0;
699 /* Make sure we've looked up the inferior's dynamic linker's base
703 debug_base
= locate_base ();
705 /* If we can't find the dynamic linker's base structure, this
706 must not be a dynamically linked executable. Hmm. */
708 return svr4_default_sos ();
711 /* Walk the inferior's link map list, and build our list of
712 `struct so_list' nodes. */
713 lm
= solib_svr4_r_map ();
717 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
718 struct so_list
*new = XZALLOC (struct so_list
);
719 struct cleanup
*old_chain
= make_cleanup (xfree
, new);
721 new->lm_info
= xmalloc (sizeof (struct lm_info
));
722 make_cleanup (xfree
, new->lm_info
);
724 new->lm_info
->l_addr
= (CORE_ADDR
)-1;
725 new->lm_info
->lm
= xzalloc (lmo
->link_map_size
);
726 make_cleanup (xfree
, new->lm_info
->lm
);
728 read_memory (lm
, new->lm_info
->lm
, lmo
->link_map_size
);
732 /* For SVR4 versions, the first entry in the link map is for the
733 inferior executable, so we must ignore it. For some versions of
734 SVR4, it has no name. For others (Solaris 2.3 for example), it
735 does have a name, so we can no longer use a missing name to
736 decide when to ignore it. */
737 if (IGNORE_FIRST_LINK_MAP_ENTRY (new) && ldsomap
== 0)
744 /* Extract this shared object's name. */
745 target_read_string (LM_NAME (new), &buffer
,
746 SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
748 warning (_("Can't read pathname for load map: %s."),
749 safe_strerror (errcode
));
752 strncpy (new->so_name
, buffer
, SO_NAME_MAX_PATH_SIZE
- 1);
753 new->so_name
[SO_NAME_MAX_PATH_SIZE
- 1] = '\0';
755 strcpy (new->so_original_name
, new->so_name
);
758 /* If this entry has no name, or its name matches the name
759 for the main executable, don't include it in the list. */
760 if (! new->so_name
[0]
761 || match_main (new->so_name
))
767 link_ptr
= &new->next
;
771 /* On Solaris, the dynamic linker is not in the normal list of
772 shared objects, so make sure we pick it up too. Having
773 symbol information for the dynamic linker is quite crucial
774 for skipping dynamic linker resolver code. */
775 if (lm
== 0 && ldsomap
== 0)
776 lm
= ldsomap
= solib_svr4_r_ldsomap ();
778 discard_cleanups (old_chain
);
782 return svr4_default_sos ();
787 /* Get the address of the link_map for a given OBJFILE. Loop through
788 the link maps, and return the address of the one corresponding to
789 the given objfile. Note that this function takes into account that
790 objfile can be the main executable, not just a shared library. The
791 main executable has always an empty name field in the linkmap. */
794 svr4_fetch_objfile_link_map (struct objfile
*objfile
)
798 if ((debug_base
= locate_base ()) == 0)
799 return 0; /* failed somehow... */
801 /* Position ourselves on the first link map. */
802 lm
= solib_svr4_r_map ();
805 /* Get info on the layout of the r_debug and link_map structures. */
806 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
809 struct lm_info objfile_lm_info
;
810 struct cleanup
*old_chain
;
811 CORE_ADDR name_address
;
812 int l_name_size
= TYPE_LENGTH (builtin_type_void_data_ptr
);
813 gdb_byte
*l_name_buf
= xmalloc (l_name_size
);
814 old_chain
= make_cleanup (xfree
, l_name_buf
);
816 /* Set up the buffer to contain the portion of the link_map
817 structure that gdb cares about. Note that this is not the
818 whole link_map structure. */
819 objfile_lm_info
.lm
= xzalloc (lmo
->link_map_size
);
820 make_cleanup (xfree
, objfile_lm_info
.lm
);
822 /* Read the link map into our internal structure. */
823 read_memory (lm
, objfile_lm_info
.lm
, lmo
->link_map_size
);
825 /* Read address of name from target memory to GDB. */
826 read_memory (lm
+ lmo
->l_name_offset
, l_name_buf
, l_name_size
);
828 /* Extract this object's name. */
829 name_address
= extract_typed_address (l_name_buf
,
830 builtin_type_void_data_ptr
);
831 target_read_string (name_address
, &buffer
,
832 SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
833 make_cleanup (xfree
, buffer
);
835 warning (_("Can't read pathname for load map: %s."),
836 safe_strerror (errcode
));
839 /* Is this the linkmap for the file we want? */
840 /* If the file is not a shared library and has no name,
841 we are sure it is the main executable, so we return that. */
842 if ((buffer
&& strcmp (buffer
, objfile
->name
) == 0)
843 || (!(objfile
->flags
& OBJF_SHARED
) && (strcmp (buffer
, "") == 0)))
845 do_cleanups (old_chain
);
849 /* Not the file we wanted, continue checking. */
850 lm
= extract_typed_address (objfile_lm_info
.lm
+ lmo
->l_next_offset
,
851 builtin_type_void_data_ptr
);
852 do_cleanups (old_chain
);
857 /* On some systems, the only way to recognize the link map entry for
858 the main executable file is by looking at its name. Return
859 non-zero iff SONAME matches one of the known main executable names. */
862 match_main (char *soname
)
866 for (mainp
= main_name_list
; *mainp
!= NULL
; mainp
++)
868 if (strcmp (soname
, *mainp
) == 0)
875 /* Return 1 if PC lies in the dynamic symbol resolution code of the
876 SVR4 run time loader. */
877 static CORE_ADDR interp_text_sect_low
;
878 static CORE_ADDR interp_text_sect_high
;
879 static CORE_ADDR interp_plt_sect_low
;
880 static CORE_ADDR interp_plt_sect_high
;
883 svr4_in_dynsym_resolve_code (CORE_ADDR pc
)
885 return ((pc
>= interp_text_sect_low
&& pc
< interp_text_sect_high
)
886 || (pc
>= interp_plt_sect_low
&& pc
< interp_plt_sect_high
)
887 || in_plt_section (pc
, NULL
));
890 /* Given an executable's ABFD and target, compute the entry-point
894 exec_entry_point (struct bfd
*abfd
, struct target_ops
*targ
)
896 /* KevinB wrote ... for most targets, the address returned by
897 bfd_get_start_address() is the entry point for the start
898 function. But, for some targets, bfd_get_start_address() returns
899 the address of a function descriptor from which the entry point
900 address may be extracted. This address is extracted by
901 gdbarch_convert_from_func_ptr_addr(). The method
902 gdbarch_convert_from_func_ptr_addr() is the merely the identify
903 function for targets which don't use function descriptors. */
904 return gdbarch_convert_from_func_ptr_addr (current_gdbarch
,
905 bfd_get_start_address (abfd
),
913 enable_break -- arrange for dynamic linker to hit breakpoint
917 int enable_break (void)
921 Both the SunOS and the SVR4 dynamic linkers have, as part of their
922 debugger interface, support for arranging for the inferior to hit
923 a breakpoint after mapping in the shared libraries. This function
924 enables that breakpoint.
926 For SunOS, there is a special flag location (in_debugger) which we
927 set to 1. When the dynamic linker sees this flag set, it will set
928 a breakpoint at a location known only to itself, after saving the
929 original contents of that place and the breakpoint address itself,
930 in it's own internal structures. When we resume the inferior, it
931 will eventually take a SIGTRAP when it runs into the breakpoint.
932 We handle this (in a different place) by restoring the contents of
933 the breakpointed location (which is only known after it stops),
934 chasing around to locate the shared libraries that have been
935 loaded, then resuming.
937 For SVR4, the debugger interface structure contains a member (r_brk)
938 which is statically initialized at the time the shared library is
939 built, to the offset of a function (_r_debug_state) which is guaran-
940 teed to be called once before mapping in a library, and again when
941 the mapping is complete. At the time we are examining this member,
942 it contains only the unrelocated offset of the function, so we have
943 to do our own relocation. Later, when the dynamic linker actually
944 runs, it relocates r_brk to be the actual address of _r_debug_state().
946 The debugger interface structure also contains an enumeration which
947 is set to either RT_ADD or RT_DELETE prior to changing the mapping,
948 depending upon whether or not the library is being mapped or unmapped,
949 and then set to RT_CONSISTENT after the library is mapped/unmapped.
955 #ifdef BKPT_AT_SYMBOL
957 struct minimal_symbol
*msymbol
;
959 asection
*interp_sect
;
961 /* First, remove all the solib event breakpoints. Their addresses
962 may have changed since the last time we ran the program. */
963 remove_solib_event_breakpoints ();
965 interp_text_sect_low
= interp_text_sect_high
= 0;
966 interp_plt_sect_low
= interp_plt_sect_high
= 0;
968 /* Find the .interp section; if not found, warn the user and drop
969 into the old breakpoint at symbol code. */
970 interp_sect
= bfd_get_section_by_name (exec_bfd
, ".interp");
973 unsigned int interp_sect_size
;
975 CORE_ADDR load_addr
= 0;
976 int load_addr_found
= 0;
979 struct target_ops
*tmp_bfd_target
;
981 char *tmp_pathname
= NULL
;
982 CORE_ADDR sym_addr
= 0;
984 /* Read the contents of the .interp section into a local buffer;
985 the contents specify the dynamic linker this program uses. */
986 interp_sect_size
= bfd_section_size (exec_bfd
, interp_sect
);
987 buf
= alloca (interp_sect_size
);
988 bfd_get_section_contents (exec_bfd
, interp_sect
,
989 buf
, 0, interp_sect_size
);
991 /* Now we need to figure out where the dynamic linker was
992 loaded so that we can load its symbols and place a breakpoint
993 in the dynamic linker itself.
995 This address is stored on the stack. However, I've been unable
996 to find any magic formula to find it for Solaris (appears to
997 be trivial on GNU/Linux). Therefore, we have to try an alternate
998 mechanism to find the dynamic linker's base address. */
1000 /* TODO drow/2006-09-12: This is somewhat fragile, because it
1001 relies on read_pc. On both Solaris and GNU/Linux we can use
1002 the AT_BASE auxilliary entry, which GDB now knows how to
1003 access, to find the base address. */
1005 tmp_fd
= solib_open (buf
, &tmp_pathname
);
1007 tmp_bfd
= bfd_fopen (tmp_pathname
, gnutarget
, FOPEN_RB
, tmp_fd
);
1009 if (tmp_bfd
== NULL
)
1010 goto bkpt_at_symbol
;
1012 /* Make sure the dynamic linker's really a useful object. */
1013 if (!bfd_check_format (tmp_bfd
, bfd_object
))
1015 warning (_("Unable to grok dynamic linker %s as an object file"), buf
);
1016 bfd_close (tmp_bfd
);
1017 goto bkpt_at_symbol
;
1020 /* Now convert the TMP_BFD into a target. That way target, as
1021 well as BFD operations can be used. Note that closing the
1022 target will also close the underlying bfd. */
1023 tmp_bfd_target
= target_bfd_reopen (tmp_bfd
);
1025 /* On a running target, we can get the dynamic linker's base
1026 address from the shared library table. */
1027 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
1028 so
= master_so_list ();
1031 if (strcmp (buf
, so
->so_original_name
) == 0)
1033 load_addr_found
= 1;
1034 load_addr
= LM_ADDR_CHECK (so
, tmp_bfd
);
1040 /* Otherwise we find the dynamic linker's base address by examining
1041 the current pc (which should point at the entry point for the
1042 dynamic linker) and subtracting the offset of the entry point. */
1043 if (!load_addr_found
)
1045 load_addr
= (read_pc ()
1046 - exec_entry_point (tmp_bfd
, tmp_bfd_target
));
1047 debug_loader_name
= xstrdup (buf
);
1048 debug_loader_offset_p
= 1;
1049 debug_loader_offset
= load_addr
;
1050 solib_add (NULL
, 0, ¤t_target
, auto_solib_add
);
1053 /* Record the relocated start and end address of the dynamic linker
1054 text and plt section for svr4_in_dynsym_resolve_code. */
1055 interp_sect
= bfd_get_section_by_name (tmp_bfd
, ".text");
1058 interp_text_sect_low
=
1059 bfd_section_vma (tmp_bfd
, interp_sect
) + load_addr
;
1060 interp_text_sect_high
=
1061 interp_text_sect_low
+ bfd_section_size (tmp_bfd
, interp_sect
);
1063 interp_sect
= bfd_get_section_by_name (tmp_bfd
, ".plt");
1066 interp_plt_sect_low
=
1067 bfd_section_vma (tmp_bfd
, interp_sect
) + load_addr
;
1068 interp_plt_sect_high
=
1069 interp_plt_sect_low
+ bfd_section_size (tmp_bfd
, interp_sect
);
1072 /* Now try to set a breakpoint in the dynamic linker. */
1073 for (bkpt_namep
= solib_break_names
; *bkpt_namep
!= NULL
; bkpt_namep
++)
1075 sym_addr
= bfd_lookup_symbol (tmp_bfd
, *bkpt_namep
);
1081 /* Convert 'sym_addr' from a function pointer to an address.
1082 Because we pass tmp_bfd_target instead of the current
1083 target, this will always produce an unrelocated value. */
1084 sym_addr
= gdbarch_convert_from_func_ptr_addr (current_gdbarch
,
1088 /* We're done with both the temporary bfd and target. Remember,
1089 closing the target closes the underlying bfd. */
1090 target_close (tmp_bfd_target
, 0);
1094 create_solib_event_breakpoint (load_addr
+ sym_addr
);
1098 /* For whatever reason we couldn't set a breakpoint in the dynamic
1099 linker. Warn and drop into the old code. */
1101 warning (_("Unable to find dynamic linker breakpoint function.\n"
1102 "GDB will be unable to debug shared library initializers\n"
1103 "and track explicitly loaded dynamic code."));
1106 /* Scan through the lists of symbols, trying to look up the symbol and
1107 set a breakpoint there. Terminate loop when we/if we succeed. */
1109 for (bkpt_namep
= solib_break_names
; *bkpt_namep
!= NULL
; bkpt_namep
++)
1111 msymbol
= lookup_minimal_symbol (*bkpt_namep
, NULL
, symfile_objfile
);
1112 if ((msymbol
!= NULL
) && (SYMBOL_VALUE_ADDRESS (msymbol
) != 0))
1114 create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol
));
1119 for (bkpt_namep
= bkpt_names
; *bkpt_namep
!= NULL
; bkpt_namep
++)
1121 msymbol
= lookup_minimal_symbol (*bkpt_namep
, NULL
, symfile_objfile
);
1122 if ((msymbol
!= NULL
) && (SYMBOL_VALUE_ADDRESS (msymbol
) != 0))
1124 create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol
));
1128 #endif /* BKPT_AT_SYMBOL */
1137 special_symbol_handling -- additional shared library symbol handling
1141 void special_symbol_handling ()
1145 Once the symbols from a shared object have been loaded in the usual
1146 way, we are called to do any system specific symbol handling that
1149 For SunOS4, this consisted of grunging around in the dynamic
1150 linkers structures to find symbol definitions for "common" symbols
1151 and adding them to the minimal symbol table for the runtime common
1154 However, for SVR4, there's nothing to do.
1159 svr4_special_symbol_handling (void)
1163 /* Relocate the main executable. This function should be called upon
1164 stopping the inferior process at the entry point to the program.
1165 The entry point from BFD is compared to the PC and if they are
1166 different, the main executable is relocated by the proper amount.
1168 As written it will only attempt to relocate executables which
1169 lack interpreter sections. It seems likely that only dynamic
1170 linker executables will get relocated, though it should work
1171 properly for a position-independent static executable as well. */
1174 svr4_relocate_main_executable (void)
1176 asection
*interp_sect
;
1177 CORE_ADDR pc
= read_pc ();
1179 /* Decide if the objfile needs to be relocated. As indicated above,
1180 we will only be here when execution is stopped at the beginning
1181 of the program. Relocation is necessary if the address at which
1182 we are presently stopped differs from the start address stored in
1183 the executable AND there's no interpreter section. The condition
1184 regarding the interpreter section is very important because if
1185 there *is* an interpreter section, execution will begin there
1186 instead. When there is an interpreter section, the start address
1187 is (presumably) used by the interpreter at some point to start
1188 execution of the program.
1190 If there is an interpreter, it is normal for it to be set to an
1191 arbitrary address at the outset. The job of finding it is
1192 handled in enable_break().
1194 So, to summarize, relocations are necessary when there is no
1195 interpreter section and the start address obtained from the
1196 executable is different from the address at which GDB is
1199 [ The astute reader will note that we also test to make sure that
1200 the executable in question has the DYNAMIC flag set. It is my
1201 opinion that this test is unnecessary (undesirable even). It
1202 was added to avoid inadvertent relocation of an executable
1203 whose e_type member in the ELF header is not ET_DYN. There may
1204 be a time in the future when it is desirable to do relocations
1205 on other types of files as well in which case this condition
1206 should either be removed or modified to accomodate the new file
1207 type. (E.g, an ET_EXEC executable which has been built to be
1208 position-independent could safely be relocated by the OS if
1209 desired. It is true that this violates the ABI, but the ABI
1210 has been known to be bent from time to time.) - Kevin, Nov 2000. ]
1213 interp_sect
= bfd_get_section_by_name (exec_bfd
, ".interp");
1214 if (interp_sect
== NULL
1215 && (bfd_get_file_flags (exec_bfd
) & DYNAMIC
) != 0
1216 && (exec_entry_point (exec_bfd
, &exec_ops
) != pc
))
1218 struct cleanup
*old_chain
;
1219 struct section_offsets
*new_offsets
;
1221 CORE_ADDR displacement
;
1223 /* It is necessary to relocate the objfile. The amount to
1224 relocate by is simply the address at which we are stopped
1225 minus the starting address from the executable.
1227 We relocate all of the sections by the same amount. This
1228 behavior is mandated by recent editions of the System V ABI.
1229 According to the System V Application Binary Interface,
1230 Edition 4.1, page 5-5:
1232 ... Though the system chooses virtual addresses for
1233 individual processes, it maintains the segments' relative
1234 positions. Because position-independent code uses relative
1235 addressesing between segments, the difference between
1236 virtual addresses in memory must match the difference
1237 between virtual addresses in the file. The difference
1238 between the virtual address of any segment in memory and
1239 the corresponding virtual address in the file is thus a
1240 single constant value for any one executable or shared
1241 object in a given process. This difference is the base
1242 address. One use of the base address is to relocate the
1243 memory image of the program during dynamic linking.
1245 The same language also appears in Edition 4.0 of the System V
1246 ABI and is left unspecified in some of the earlier editions. */
1248 displacement
= pc
- exec_entry_point (exec_bfd
, &exec_ops
);
1251 new_offsets
= xcalloc (symfile_objfile
->num_sections
,
1252 sizeof (struct section_offsets
));
1253 old_chain
= make_cleanup (xfree
, new_offsets
);
1255 for (i
= 0; i
< symfile_objfile
->num_sections
; i
++)
1257 if (displacement
!= ANOFFSET (symfile_objfile
->section_offsets
, i
))
1259 new_offsets
->offsets
[i
] = displacement
;
1263 objfile_relocate (symfile_objfile
, new_offsets
);
1265 do_cleanups (old_chain
);
1273 svr4_solib_create_inferior_hook -- shared library startup support
1277 void svr4_solib_create_inferior_hook ()
1281 When gdb starts up the inferior, it nurses it along (through the
1282 shell) until it is ready to execute it's first instruction. At this
1283 point, this function gets called via expansion of the macro
1284 SOLIB_CREATE_INFERIOR_HOOK.
1286 For SunOS executables, this first instruction is typically the
1287 one at "_start", or a similar text label, regardless of whether
1288 the executable is statically or dynamically linked. The runtime
1289 startup code takes care of dynamically linking in any shared
1290 libraries, once gdb allows the inferior to continue.
1292 For SVR4 executables, this first instruction is either the first
1293 instruction in the dynamic linker (for dynamically linked
1294 executables) or the instruction at "start" for statically linked
1295 executables. For dynamically linked executables, the system
1296 first exec's /lib/libc.so.N, which contains the dynamic linker,
1297 and starts it running. The dynamic linker maps in any needed
1298 shared libraries, maps in the actual user executable, and then
1299 jumps to "start" in the user executable.
1301 For both SunOS shared libraries, and SVR4 shared libraries, we
1302 can arrange to cooperate with the dynamic linker to discover the
1303 names of shared libraries that are dynamically linked, and the
1304 base addresses to which they are linked.
1306 This function is responsible for discovering those names and
1307 addresses, and saving sufficient information about them to allow
1308 their symbols to be read at a later time.
1312 Between enable_break() and disable_break(), this code does not
1313 properly handle hitting breakpoints which the user might have
1314 set in the startup code or in the dynamic linker itself. Proper
1315 handling will probably have to wait until the implementation is
1316 changed to use the "breakpoint handler function" method.
1318 Also, what if child has exit()ed? Must exit loop somehow.
1322 svr4_solib_create_inferior_hook (void)
1324 /* Relocate the main executable if necessary. */
1325 svr4_relocate_main_executable ();
1327 if (!svr4_have_link_map_offsets ())
1330 if (!enable_break ())
1333 #if defined(_SCO_DS)
1334 /* SCO needs the loop below, other systems should be using the
1335 special shared library breakpoints and the shared library breakpoint
1338 Now run the target. It will eventually hit the breakpoint, at
1339 which point all of the libraries will have been mapped in and we
1340 can go groveling around in the dynamic linker structures to find
1341 out what we need to know about them. */
1343 clear_proceed_status ();
1344 stop_soon
= STOP_QUIETLY
;
1345 stop_signal
= TARGET_SIGNAL_0
;
1348 target_resume (pid_to_ptid (-1), 0, stop_signal
);
1349 wait_for_inferior ();
1351 while (stop_signal
!= TARGET_SIGNAL_TRAP
);
1352 stop_soon
= NO_STOP_QUIETLY
;
1353 #endif /* defined(_SCO_DS) */
1357 svr4_clear_solib (void)
1360 debug_loader_offset_p
= 0;
1361 debug_loader_offset
= 0;
1362 xfree (debug_loader_name
);
1363 debug_loader_name
= NULL
;
1367 svr4_free_so (struct so_list
*so
)
1369 xfree (so
->lm_info
->lm
);
1370 xfree (so
->lm_info
);
1374 /* Clear any bits of ADDR that wouldn't fit in a target-format
1375 data pointer. "Data pointer" here refers to whatever sort of
1376 address the dynamic linker uses to manage its sections. At the
1377 moment, we don't support shared libraries on any processors where
1378 code and data pointers are different sizes.
1380 This isn't really the right solution. What we really need here is
1381 a way to do arithmetic on CORE_ADDR values that respects the
1382 natural pointer/address correspondence. (For example, on the MIPS,
1383 converting a 32-bit pointer to a 64-bit CORE_ADDR requires you to
1384 sign-extend the value. There, simply truncating the bits above
1385 gdbarch_ptr_bit, as we do below, is no good.) This should probably
1386 be a new gdbarch method or something. */
1388 svr4_truncate_ptr (CORE_ADDR addr
)
1390 if (gdbarch_ptr_bit (current_gdbarch
) == sizeof (CORE_ADDR
) * 8)
1391 /* We don't need to truncate anything, and the bit twiddling below
1392 will fail due to overflow problems. */
1395 return addr
& (((CORE_ADDR
) 1 << gdbarch_ptr_bit (current_gdbarch
)) - 1);
1400 svr4_relocate_section_addresses (struct so_list
*so
,
1401 struct section_table
*sec
)
1403 sec
->addr
= svr4_truncate_ptr (sec
->addr
+ LM_ADDR_CHECK (so
,
1405 sec
->endaddr
= svr4_truncate_ptr (sec
->endaddr
+ LM_ADDR_CHECK (so
,
1410 /* Architecture-specific operations. */
1412 /* Per-architecture data key. */
1413 static struct gdbarch_data
*solib_svr4_data
;
1415 struct solib_svr4_ops
1417 /* Return a description of the layout of `struct link_map'. */
1418 struct link_map_offsets
*(*fetch_link_map_offsets
)(void);
1421 /* Return a default for the architecture-specific operations. */
1424 solib_svr4_init (struct obstack
*obstack
)
1426 struct solib_svr4_ops
*ops
;
1428 ops
= OBSTACK_ZALLOC (obstack
, struct solib_svr4_ops
);
1429 ops
->fetch_link_map_offsets
= legacy_svr4_fetch_link_map_offsets_hook
;
1433 /* Set the architecture-specific `struct link_map_offsets' fetcher for
1437 set_solib_svr4_fetch_link_map_offsets (struct gdbarch
*gdbarch
,
1438 struct link_map_offsets
*(*flmo
) (void))
1440 struct solib_svr4_ops
*ops
= gdbarch_data (gdbarch
, solib_svr4_data
);
1442 ops
->fetch_link_map_offsets
= flmo
;
1445 /* Fetch a link_map_offsets structure using the architecture-specific
1446 `struct link_map_offsets' fetcher. */
1448 static struct link_map_offsets
*
1449 svr4_fetch_link_map_offsets (void)
1451 struct solib_svr4_ops
*ops
= gdbarch_data (current_gdbarch
, solib_svr4_data
);
1453 gdb_assert (ops
->fetch_link_map_offsets
);
1454 return ops
->fetch_link_map_offsets ();
1457 /* Return 1 if a link map offset fetcher has been defined, 0 otherwise. */
1460 svr4_have_link_map_offsets (void)
1462 struct solib_svr4_ops
*ops
= gdbarch_data (current_gdbarch
, solib_svr4_data
);
1463 return (ops
->fetch_link_map_offsets
!= NULL
);
1467 /* Most OS'es that have SVR4-style ELF dynamic libraries define a
1468 `struct r_debug' and a `struct link_map' that are binary compatible
1469 with the origional SVR4 implementation. */
1471 /* Fetch (and possibly build) an appropriate `struct link_map_offsets'
1472 for an ILP32 SVR4 system. */
1474 struct link_map_offsets
*
1475 svr4_ilp32_fetch_link_map_offsets (void)
1477 static struct link_map_offsets lmo
;
1478 static struct link_map_offsets
*lmp
= NULL
;
1484 lmo
.r_version_offset
= 0;
1485 lmo
.r_version_size
= 4;
1486 lmo
.r_map_offset
= 4;
1487 lmo
.r_ldsomap_offset
= 20;
1489 /* Everything we need is in the first 20 bytes. */
1490 lmo
.link_map_size
= 20;
1491 lmo
.l_addr_offset
= 0;
1492 lmo
.l_name_offset
= 4;
1493 lmo
.l_ld_offset
= 8;
1494 lmo
.l_next_offset
= 12;
1495 lmo
.l_prev_offset
= 16;
1501 /* Fetch (and possibly build) an appropriate `struct link_map_offsets'
1502 for an LP64 SVR4 system. */
1504 struct link_map_offsets
*
1505 svr4_lp64_fetch_link_map_offsets (void)
1507 static struct link_map_offsets lmo
;
1508 static struct link_map_offsets
*lmp
= NULL
;
1514 lmo
.r_version_offset
= 0;
1515 lmo
.r_version_size
= 4;
1516 lmo
.r_map_offset
= 8;
1517 lmo
.r_ldsomap_offset
= 40;
1519 /* Everything we need is in the first 40 bytes. */
1520 lmo
.link_map_size
= 40;
1521 lmo
.l_addr_offset
= 0;
1522 lmo
.l_name_offset
= 8;
1523 lmo
.l_ld_offset
= 16;
1524 lmo
.l_next_offset
= 24;
1525 lmo
.l_prev_offset
= 32;
1532 struct target_so_ops svr4_so_ops
;
1534 /* Lookup global symbol for ELF DSOs linked with -Bsymbolic. Those DSOs have a
1535 different rule for symbol lookup. The lookup begins here in the DSO, not in
1536 the main executable. */
1538 static struct symbol
*
1539 elf_lookup_lib_symbol (const struct objfile
*objfile
,
1541 const char *linkage_name
,
1542 const domain_enum domain
, struct symtab
**symtab
)
1544 if (objfile
->obfd
== NULL
1545 || scan_dyntag (DT_SYMBOLIC
, objfile
->obfd
, NULL
) != 1)
1548 return lookup_global_symbol_from_objfile
1549 (objfile
, name
, linkage_name
, domain
, symtab
);
1552 extern initialize_file_ftype _initialize_svr4_solib
; /* -Wmissing-prototypes */
1555 _initialize_svr4_solib (void)
1557 solib_svr4_data
= gdbarch_data_register_pre_init (solib_svr4_init
);
1559 svr4_so_ops
.relocate_section_addresses
= svr4_relocate_section_addresses
;
1560 svr4_so_ops
.free_so
= svr4_free_so
;
1561 svr4_so_ops
.clear_solib
= svr4_clear_solib
;
1562 svr4_so_ops
.solib_create_inferior_hook
= svr4_solib_create_inferior_hook
;
1563 svr4_so_ops
.special_symbol_handling
= svr4_special_symbol_handling
;
1564 svr4_so_ops
.current_sos
= svr4_current_sos
;
1565 svr4_so_ops
.open_symbol_file_object
= open_symbol_file_object
;
1566 svr4_so_ops
.in_dynsym_resolve_code
= svr4_in_dynsym_resolve_code
;
1567 svr4_so_ops
.lookup_lib_global_symbol
= elf_lookup_lib_symbol
;
1569 /* FIXME: Don't do this here. *_gdbarch_init() should set so_ops. */
1570 current_target_so_ops
= &svr4_so_ops
;