851 lines
26 KiB
C
851 lines
26 KiB
C
/* Read ELF (Executable and Linking Format) object files for GDB.
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Copyright 1991, 92, 93, 94, 95, 96, 1998 Free Software Foundation, Inc.
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Written by Fred Fish at Cygnus Support.
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software
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Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
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#include "defs.h"
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#include "bfd.h"
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#include "gdb_string.h"
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#include "elf-bfd.h"
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#include "elf/mips.h"
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#include "symtab.h"
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#include "symfile.h"
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#include "objfiles.h"
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#include "buildsym.h"
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#include "stabsread.h"
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#include "gdb-stabs.h"
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#include "complaints.h"
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#include "demangle.h"
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extern void _initialize_elfread PARAMS ((void));
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/* The struct elfinfo is available only during ELF symbol table and
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psymtab reading. It is destroyed at the complation of psymtab-reading.
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It's local to elf_symfile_read. */
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struct elfinfo {
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file_ptr dboffset; /* Offset to dwarf debug section */
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unsigned int dbsize; /* Size of dwarf debug section */
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file_ptr lnoffset; /* Offset to dwarf line number section */
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unsigned int lnsize; /* Size of dwarf line number section */
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asection *stabsect; /* Section pointer for .stab section */
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asection *stabindexsect; /* Section pointer for .stab.index section */
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asection *mdebugsect; /* Section pointer for .mdebug section */
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};
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/* Various things we might complain about... */
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struct complaint section_info_complaint =
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{"elf/stab section information %s without a preceding file symbol", 0, 0};
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struct complaint section_info_dup_complaint =
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{"duplicated elf/stab section information for %s", 0, 0};
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struct complaint stab_info_mismatch_complaint =
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{"elf/stab section information missing for %s", 0, 0};
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struct complaint stab_info_questionable_complaint =
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{"elf/stab section information questionable for %s", 0, 0};
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static void
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elf_symfile_init PARAMS ((struct objfile *));
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static void
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elf_new_init PARAMS ((struct objfile *));
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static void
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elf_symfile_read PARAMS ((struct objfile *, struct section_offsets *, int));
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static void
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elf_symfile_finish PARAMS ((struct objfile *));
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static void
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elf_symtab_read PARAMS ((bfd *, CORE_ADDR, struct objfile *, int));
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static void
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free_elfinfo PARAMS ((void *));
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static struct minimal_symbol *
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record_minimal_symbol_and_info PARAMS ((char *, CORE_ADDR,
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enum minimal_symbol_type, char *,
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asection *bfd_section,
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struct objfile *));
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static void
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elf_locate_sections PARAMS ((bfd *, asection *, void *));
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/* We are called once per section from elf_symfile_read. We
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need to examine each section we are passed, check to see
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if it is something we are interested in processing, and
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if so, stash away some access information for the section.
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For now we recognize the dwarf debug information sections and
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line number sections from matching their section names. The
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ELF definition is no real help here since it has no direct
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knowledge of DWARF (by design, so any debugging format can be
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used).
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We also recognize the ".stab" sections used by the Sun compilers
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released with Solaris 2.
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FIXME: The section names should not be hardwired strings (what
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should they be? I don't think most object file formats have enough
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section flags to specify what kind of debug section it is
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-kingdon). */
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static void
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elf_locate_sections (ignore_abfd, sectp, eip)
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bfd *ignore_abfd;
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asection *sectp;
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PTR eip;
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{
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register struct elfinfo *ei;
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ei = (struct elfinfo *) eip;
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if (STREQ (sectp -> name, ".debug"))
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{
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ei -> dboffset = sectp -> filepos;
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ei -> dbsize = bfd_get_section_size_before_reloc (sectp);
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}
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else if (STREQ (sectp -> name, ".line"))
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{
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ei -> lnoffset = sectp -> filepos;
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ei -> lnsize = bfd_get_section_size_before_reloc (sectp);
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}
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else if (STREQ (sectp -> name, ".stab"))
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{
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ei -> stabsect = sectp;
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}
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else if (STREQ (sectp -> name, ".stab.index"))
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{
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ei -> stabindexsect = sectp;
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}
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else if (STREQ (sectp -> name, ".mdebug"))
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{
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ei -> mdebugsect = sectp;
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}
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}
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#if 0 /* Currently unused */
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char *
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elf_interpreter (abfd)
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bfd *abfd;
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{
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sec_ptr interp_sec;
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unsigned size;
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char *interp = NULL;
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interp_sec = bfd_get_section_by_name (abfd, ".interp");
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if (interp_sec)
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{
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size = bfd_section_size (abfd, interp_sec);
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interp = alloca (size);
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if (bfd_get_section_contents (abfd, interp_sec, interp, (file_ptr)0,
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size))
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{
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interp = savestring (interp, size - 1);
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}
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else
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{
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interp = NULL;
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}
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}
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return (interp);
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}
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#endif
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static struct minimal_symbol *
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record_minimal_symbol_and_info (name, address, ms_type, info, bfd_section,
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objfile)
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char *name;
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CORE_ADDR address;
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enum minimal_symbol_type ms_type;
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char *info; /* FIXME, is this really char *? */
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asection *bfd_section;
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struct objfile *objfile;
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{
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int section;
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/* Guess the section from the type. This is likely to be wrong in
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some cases. */
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switch (ms_type)
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{
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case mst_text:
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case mst_file_text:
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section = SECT_OFF_TEXT;
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#ifdef SMASH_TEXT_ADDRESS
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SMASH_TEXT_ADDRESS (address);
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#endif
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break;
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case mst_data:
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case mst_file_data:
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section = SECT_OFF_DATA;
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break;
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case mst_bss:
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case mst_file_bss:
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section = SECT_OFF_BSS;
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break;
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default:
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section = -1;
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break;
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}
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return prim_record_minimal_symbol_and_info
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(name, address, ms_type, info, section, bfd_section, objfile);
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}
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/*
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LOCAL FUNCTION
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elf_symtab_read -- read the symbol table of an ELF file
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SYNOPSIS
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void elf_symtab_read (bfd *abfd, CORE_ADDR addr,
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struct objfile *objfile, int dynamic)
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DESCRIPTION
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Given an open bfd, a base address to relocate symbols to, and a
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flag that specifies whether or not this bfd is for an executable
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or not (may be shared library for example), add all the global
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function and data symbols to the minimal symbol table.
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In stabs-in-ELF, as implemented by Sun, there are some local symbols
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defined in the ELF symbol table, which can be used to locate
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the beginnings of sections from each ".o" file that was linked to
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form the executable objfile. We gather any such info and record it
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in data structures hung off the objfile's private data.
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*/
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static void
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elf_symtab_read (abfd, addr, objfile, dynamic)
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bfd *abfd;
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CORE_ADDR addr;
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struct objfile *objfile;
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int dynamic;
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{
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long storage_needed;
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asymbol *sym;
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asymbol **symbol_table;
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long number_of_symbols;
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long i;
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int index;
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struct cleanup *back_to;
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CORE_ADDR symaddr;
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enum minimal_symbol_type ms_type;
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/* If sectinfo is nonNULL, it contains section info that should end up
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filed in the objfile. */
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struct stab_section_info *sectinfo = NULL;
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/* If filesym is nonzero, it points to a file symbol, but we haven't
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seen any section info for it yet. */
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asymbol *filesym = 0;
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#ifdef SOFUN_ADDRESS_MAYBE_MISSING
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/* Name of filesym, as saved on the symbol_obstack. */
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char *filesymname = obsavestring ("", 0, &objfile->symbol_obstack);
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#endif
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struct dbx_symfile_info *dbx = objfile->sym_stab_info;
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unsigned long size;
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int stripped = (bfd_get_symcount (abfd) == 0);
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if (dynamic)
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{
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storage_needed = bfd_get_dynamic_symtab_upper_bound (abfd);
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/* Nothing to be done if there is no dynamic symtab. */
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if (storage_needed < 0)
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return;
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}
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else
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{
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storage_needed = bfd_get_symtab_upper_bound (abfd);
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if (storage_needed < 0)
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error ("Can't read symbols from %s: %s", bfd_get_filename (abfd),
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bfd_errmsg (bfd_get_error ()));
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}
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if (storage_needed > 0)
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{
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symbol_table = (asymbol **) xmalloc (storage_needed);
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back_to = make_cleanup (free, symbol_table);
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if (dynamic)
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number_of_symbols = bfd_canonicalize_dynamic_symtab (abfd,
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symbol_table);
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else
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number_of_symbols = bfd_canonicalize_symtab (abfd, symbol_table);
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if (number_of_symbols < 0)
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error ("Can't read symbols from %s: %s", bfd_get_filename (abfd),
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bfd_errmsg (bfd_get_error ()));
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for (i = 0; i < number_of_symbols; i++)
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{
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sym = symbol_table[i];
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if (sym -> name == NULL || *sym -> name == '\0')
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{
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/* Skip names that don't exist (shouldn't happen), or names
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that are null strings (may happen). */
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continue;
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}
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if (dynamic
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&& sym -> section == &bfd_und_section
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&& (sym -> flags & BSF_FUNCTION))
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{
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struct minimal_symbol *msym;
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/* Symbol is a reference to a function defined in
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a shared library.
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If its value is non zero then it is usually the address
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of the corresponding entry in the procedure linkage table,
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relative to the base address.
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If its value is zero then the dynamic linker has to resolve
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the symbol. We are unable to find any meaningful address
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for this symbol in the executable file, so we skip it. */
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symaddr = sym -> value;
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if (symaddr == 0)
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continue;
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symaddr += addr;
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msym = record_minimal_symbol_and_info
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((char *) sym -> name, symaddr,
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mst_solib_trampoline, NULL, sym -> section, objfile);
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#ifdef SOFUN_ADDRESS_MAYBE_MISSING
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if (msym != NULL)
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msym->filename = filesymname;
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#endif
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continue;
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}
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/* If it is a nonstripped executable, do not enter dynamic
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symbols, as the dynamic symbol table is usually a subset
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of the main symbol table. */
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if (dynamic && !stripped)
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continue;
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if (sym -> flags & BSF_FILE)
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{
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/* STT_FILE debugging symbol that helps stabs-in-elf debugging.
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Chain any old one onto the objfile; remember new sym. */
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if (sectinfo != NULL)
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{
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sectinfo -> next = dbx -> stab_section_info;
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dbx -> stab_section_info = sectinfo;
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sectinfo = NULL;
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}
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filesym = sym;
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#ifdef SOFUN_ADDRESS_MAYBE_MISSING
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filesymname =
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obsavestring ((char *)filesym->name, strlen (filesym->name),
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&objfile->symbol_obstack);
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#endif
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}
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else if (sym -> flags & (BSF_GLOBAL | BSF_LOCAL | BSF_WEAK))
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{
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struct minimal_symbol *msym;
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/* Select global/local/weak symbols. Note that bfd puts abs
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symbols in their own section, so all symbols we are
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interested in will have a section. */
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/* Bfd symbols are section relative. */
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symaddr = sym -> value + sym -> section -> vma;
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/* Relocate all non-absolute symbols by base address. */
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if (sym -> section != &bfd_abs_section)
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{
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symaddr += addr;
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}
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/* For non-absolute symbols, use the type of the section
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they are relative to, to intuit text/data. Bfd provides
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no way of figuring this out for absolute symbols. */
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if (sym -> section == &bfd_abs_section)
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{
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/* This is a hack to get the minimal symbol type
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right for Irix 5, which has absolute adresses
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with special section indices for dynamic symbols. */
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unsigned short shndx =
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((elf_symbol_type *) sym)->internal_elf_sym.st_shndx;
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switch (shndx)
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{
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case SHN_MIPS_TEXT:
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ms_type = mst_text;
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break;
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case SHN_MIPS_DATA:
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ms_type = mst_data;
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break;
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case SHN_MIPS_ACOMMON:
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ms_type = mst_bss;
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break;
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default:
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ms_type = mst_abs;
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}
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/* If it is an Irix dynamic symbol, skip section name
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symbols, relocate all others. */
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if (ms_type != mst_abs)
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{
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if (sym->name[0] == '.')
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continue;
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symaddr += addr;
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}
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}
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else if (sym -> section -> flags & SEC_CODE)
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{
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if (sym -> flags & BSF_GLOBAL)
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{
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ms_type = mst_text;
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}
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else if ((sym->name[0] == '.' && sym->name[1] == 'L')
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|| ((sym -> flags & BSF_LOCAL)
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&& sym->name[0] == '$'
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&& sym->name[1] == 'L'))
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/* Looks like a compiler-generated label. Skip it.
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The assembler should be skipping these (to keep
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executables small), but apparently with gcc on the
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delta m88k SVR4, it loses. So to have us check too
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should be harmless (but I encourage people to fix this
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in the assembler instead of adding checks here). */
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continue;
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#ifdef HARRIS_TARGET
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else if (sym->name[0] == '.' && sym->name[1] == '.')
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{
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/* Looks like a Harris compiler generated label for the
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purpose of marking instructions that are relevant to
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DWARF dies. The assembler can't get rid of these
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because they are relocatable addresses that the
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linker needs to resolve. */
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continue;
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}
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#endif
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else
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{
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ms_type = mst_file_text;
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}
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}
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else if (sym -> section -> flags & SEC_ALLOC)
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{
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if (sym -> flags & BSF_GLOBAL)
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{
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if (sym -> section -> flags & SEC_LOAD)
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{
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ms_type = mst_data;
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}
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else
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{
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ms_type = mst_bss;
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}
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}
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else if (sym -> flags & BSF_LOCAL)
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{
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/* Named Local variable in a Data section. Check its
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name for stabs-in-elf. The STREQ macro checks the
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first character inline, so we only actually do a
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strcmp function call on names that start with 'B'
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or 'D' */
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index = SECT_OFF_MAX;
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if (STREQ ("Bbss.bss", sym -> name))
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{
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index = SECT_OFF_BSS;
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}
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else if (STREQ ("Ddata.data", sym -> name))
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{
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index = SECT_OFF_DATA;
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}
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else if (STREQ ("Drodata.rodata", sym -> name))
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{
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index = SECT_OFF_RODATA;
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}
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if (index != SECT_OFF_MAX)
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{
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/* Found a special local symbol. Allocate a
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sectinfo, if needed, and fill it in. */
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if (sectinfo == NULL)
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{
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sectinfo = (struct stab_section_info *)
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xmmalloc (objfile -> md, sizeof (*sectinfo));
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memset ((PTR) sectinfo, 0, sizeof (*sectinfo));
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if (filesym == NULL)
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{
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complain (§ion_info_complaint,
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sym -> name);
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}
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else
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{
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sectinfo -> filename =
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(char *) filesym -> name;
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}
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}
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if (sectinfo -> sections[index] != 0)
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{
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complain (§ion_info_dup_complaint,
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sectinfo -> filename);
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}
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/* Bfd symbols are section relative. */
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symaddr = sym -> value + sym -> section -> vma;
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/* Relocate non-absolute symbols by base address. */
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if (sym -> section != &bfd_abs_section)
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{
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symaddr += addr;
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}
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sectinfo -> sections[index] = symaddr;
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/* The special local symbols don't go in the
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minimal symbol table, so ignore this one. */
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continue;
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}
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/* Not a special stabs-in-elf symbol, do regular
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symbol processing. */
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if (sym -> section -> flags & SEC_LOAD)
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{
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ms_type = mst_file_data;
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}
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else
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{
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ms_type = mst_file_bss;
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}
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}
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else
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{
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ms_type = mst_unknown;
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}
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}
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else
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{
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/* FIXME: Solaris2 shared libraries include lots of
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odd "absolute" and "undefined" symbols, that play
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hob with actions like finding what function the PC
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is in. Ignore them if they aren't text, data, or bss. */
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/* ms_type = mst_unknown; */
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continue; /* Skip this symbol. */
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}
|
||
/* Pass symbol size field in via BFD. FIXME!!! */
|
||
size = ((elf_symbol_type *) sym) -> internal_elf_sym.st_size;
|
||
msym = record_minimal_symbol_and_info
|
||
((char *) sym -> name, symaddr,
|
||
ms_type, (PTR) size, sym -> section, objfile);
|
||
#ifdef SOFUN_ADDRESS_MAYBE_MISSING
|
||
if (msym != NULL)
|
||
msym->filename = filesymname;
|
||
#endif
|
||
#ifdef ELF_MAKE_MSYMBOL_SPECIAL
|
||
ELF_MAKE_MSYMBOL_SPECIAL(sym,msym);
|
||
#endif
|
||
}
|
||
}
|
||
do_cleanups (back_to);
|
||
}
|
||
}
|
||
|
||
/* Scan and build partial symbols for a symbol file.
|
||
We have been initialized by a call to elf_symfile_init, which
|
||
currently does nothing.
|
||
|
||
SECTION_OFFSETS is a set of offsets to apply to relocate the symbols
|
||
in each section. We simplify it down to a single offset for all
|
||
symbols. FIXME.
|
||
|
||
MAINLINE is true if we are reading the main symbol
|
||
table (as opposed to a shared lib or dynamically loaded file).
|
||
|
||
This function only does the minimum work necessary for letting the
|
||
user "name" things symbolically; it does not read the entire symtab.
|
||
Instead, it reads the external and static symbols and puts them in partial
|
||
symbol tables. When more extensive information is requested of a
|
||
file, the corresponding partial symbol table is mutated into a full
|
||
fledged symbol table by going back and reading the symbols
|
||
for real.
|
||
|
||
We look for sections with specific names, to tell us what debug
|
||
format to look for: FIXME!!!
|
||
|
||
dwarf_build_psymtabs() builds psymtabs for DWARF symbols;
|
||
elfstab_build_psymtabs() handles STABS symbols;
|
||
mdebug_build_psymtabs() handles ECOFF debugging information.
|
||
|
||
Note that ELF files have a "minimal" symbol table, which looks a lot
|
||
like a COFF symbol table, but has only the minimal information necessary
|
||
for linking. We process this also, and use the information to
|
||
build gdb's minimal symbol table. This gives us some minimal debugging
|
||
capability even for files compiled without -g. */
|
||
|
||
static void
|
||
elf_symfile_read (objfile, section_offsets, mainline)
|
||
struct objfile *objfile;
|
||
struct section_offsets *section_offsets;
|
||
int mainline;
|
||
{
|
||
bfd *abfd = objfile->obfd;
|
||
struct elfinfo ei;
|
||
struct cleanup *back_to;
|
||
CORE_ADDR offset;
|
||
|
||
init_minimal_symbol_collection ();
|
||
back_to = make_cleanup ((make_cleanup_func) discard_minimal_symbols, 0);
|
||
|
||
memset ((char *) &ei, 0, sizeof (ei));
|
||
|
||
/* Allocate struct to keep track of the symfile */
|
||
objfile->sym_stab_info = (struct dbx_symfile_info *)
|
||
xmmalloc (objfile -> md, sizeof (struct dbx_symfile_info));
|
||
memset ((char *) objfile->sym_stab_info, 0, sizeof (struct dbx_symfile_info));
|
||
make_cleanup (free_elfinfo, (PTR) objfile);
|
||
|
||
/* Process the normal ELF symbol table first. This may write some
|
||
chain of info into the dbx_symfile_info in objfile->sym_stab_info,
|
||
which can later be used by elfstab_offset_sections. */
|
||
|
||
/* FIXME, should take a section_offsets param, not just an offset. */
|
||
offset = ANOFFSET (section_offsets, 0);
|
||
elf_symtab_read (abfd, offset, objfile, 0);
|
||
|
||
/* Add the dynamic symbols. */
|
||
|
||
elf_symtab_read (abfd, offset, objfile, 1);
|
||
|
||
/* Now process debugging information, which is contained in
|
||
special ELF sections. */
|
||
|
||
/* If we are reinitializing, or if we have never loaded syms yet,
|
||
set table to empty. MAINLINE is cleared so that *_read_psymtab
|
||
functions do not all also re-initialize the psymbol table. */
|
||
if (mainline)
|
||
{
|
||
init_psymbol_list (objfile, 0);
|
||
mainline = 0;
|
||
}
|
||
|
||
/* We first have to find them... */
|
||
bfd_map_over_sections (abfd, elf_locate_sections, (PTR) &ei);
|
||
|
||
/* ELF debugging information is inserted into the psymtab in the
|
||
order of least informative first - most informative last. Since
|
||
the psymtab table is searched `most recent insertion first' this
|
||
increases the probability that more detailed debug information
|
||
for a section is found.
|
||
|
||
For instance, an object file might contain both .mdebug (XCOFF)
|
||
and .debug_info (DWARF2) sections then .mdebug is inserted first
|
||
(searched last) and DWARF2 is inserted last (searched first). If
|
||
we don't do this then the XCOFF info is found first - for code in
|
||
an included file XCOFF info is useless. */
|
||
|
||
if (ei.mdebugsect)
|
||
{
|
||
const struct ecoff_debug_swap *swap;
|
||
|
||
/* .mdebug section, presumably holding ECOFF debugging
|
||
information. */
|
||
swap = get_elf_backend_data (abfd)->elf_backend_ecoff_debug_swap;
|
||
if (swap)
|
||
elfmdebug_build_psymtabs (objfile, swap, ei.mdebugsect,
|
||
section_offsets);
|
||
}
|
||
if (ei.stabsect)
|
||
{
|
||
asection *str_sect;
|
||
|
||
/* Stab sections have an associated string table that looks like
|
||
a separate section. */
|
||
str_sect = bfd_get_section_by_name (abfd, ".stabstr");
|
||
|
||
/* FIXME should probably warn about a stab section without a stabstr. */
|
||
if (str_sect)
|
||
elfstab_build_psymtabs (objfile,
|
||
section_offsets,
|
||
mainline,
|
||
ei.stabsect->filepos,
|
||
bfd_section_size (abfd, ei.stabsect),
|
||
str_sect->filepos,
|
||
bfd_section_size (abfd, str_sect));
|
||
}
|
||
if (dwarf2_has_info (abfd))
|
||
{
|
||
/* DWARF 2 sections */
|
||
dwarf2_build_psymtabs (objfile, section_offsets, mainline);
|
||
}
|
||
else if (ei.dboffset && ei.lnoffset)
|
||
{
|
||
/* DWARF sections */
|
||
dwarf_build_psymtabs (objfile,
|
||
section_offsets, mainline,
|
||
ei.dboffset, ei.dbsize,
|
||
ei.lnoffset, ei.lnsize);
|
||
}
|
||
|
||
/* Install any minimal symbols that have been collected as the current
|
||
minimal symbols for this objfile. */
|
||
|
||
install_minimal_symbols (objfile);
|
||
|
||
do_cleanups (back_to);
|
||
}
|
||
|
||
/* This cleans up the objfile's sym_stab_info pointer, and the chain of
|
||
stab_section_info's, that might be dangling from it. */
|
||
|
||
static void
|
||
free_elfinfo (objp)
|
||
PTR objp;
|
||
{
|
||
struct objfile *objfile = (struct objfile *)objp;
|
||
struct dbx_symfile_info *dbxinfo = objfile->sym_stab_info;
|
||
struct stab_section_info *ssi, *nssi;
|
||
|
||
ssi = dbxinfo->stab_section_info;
|
||
while (ssi)
|
||
{
|
||
nssi = ssi->next;
|
||
mfree (objfile->md, ssi);
|
||
ssi = nssi;
|
||
}
|
||
|
||
dbxinfo->stab_section_info = 0; /* Just say No mo info about this. */
|
||
}
|
||
|
||
|
||
/* Initialize anything that needs initializing when a completely new symbol
|
||
file is specified (not just adding some symbols from another file, e.g. a
|
||
shared library).
|
||
|
||
We reinitialize buildsym, since we may be reading stabs from an ELF file. */
|
||
|
||
static void
|
||
elf_new_init (ignore)
|
||
struct objfile *ignore;
|
||
{
|
||
stabsread_new_init ();
|
||
buildsym_new_init ();
|
||
}
|
||
|
||
/* Perform any local cleanups required when we are done with a particular
|
||
objfile. I.E, we are in the process of discarding all symbol information
|
||
for an objfile, freeing up all memory held for it, and unlinking the
|
||
objfile struct from the global list of known objfiles. */
|
||
|
||
static void
|
||
elf_symfile_finish (objfile)
|
||
struct objfile *objfile;
|
||
{
|
||
if (objfile -> sym_stab_info != NULL)
|
||
{
|
||
mfree (objfile -> md, objfile -> sym_stab_info);
|
||
}
|
||
}
|
||
|
||
/* ELF specific initialization routine for reading symbols.
|
||
|
||
It is passed a pointer to a struct sym_fns which contains, among other
|
||
things, the BFD for the file whose symbols are being read, and a slot for
|
||
a pointer to "private data" which we can fill with goodies.
|
||
|
||
For now at least, we have nothing in particular to do, so this function is
|
||
just a stub. */
|
||
|
||
static void
|
||
elf_symfile_init (objfile)
|
||
struct objfile *objfile;
|
||
{
|
||
/* ELF objects may be reordered, so set OBJF_REORDERED. If we
|
||
find this causes a significant slowdown in gdb then we could
|
||
set it in the debug symbol readers only when necessary. */
|
||
objfile->flags |= OBJF_REORDERED;
|
||
}
|
||
|
||
/* When handling an ELF file that contains Sun STABS debug info,
|
||
some of the debug info is relative to the particular chunk of the
|
||
section that was generated in its individual .o file. E.g.
|
||
offsets to static variables are relative to the start of the data
|
||
segment *for that module before linking*. This information is
|
||
painfully squirreled away in the ELF symbol table as local symbols
|
||
with wierd names. Go get 'em when needed. */
|
||
|
||
void
|
||
elfstab_offset_sections (objfile, pst)
|
||
struct objfile *objfile;
|
||
struct partial_symtab *pst;
|
||
{
|
||
char *filename = pst->filename;
|
||
struct dbx_symfile_info *dbx = objfile->sym_stab_info;
|
||
struct stab_section_info *maybe = dbx->stab_section_info;
|
||
struct stab_section_info *questionable = 0;
|
||
int i;
|
||
char *p;
|
||
|
||
/* The ELF symbol info doesn't include path names, so strip the path
|
||
(if any) from the psymtab filename. */
|
||
while (0 != (p = strchr (filename, '/')))
|
||
filename = p+1;
|
||
|
||
/* FIXME: This linear search could speed up significantly
|
||
if it was chained in the right order to match how we search it,
|
||
and if we unchained when we found a match. */
|
||
for (; maybe; maybe = maybe->next)
|
||
{
|
||
if (filename[0] == maybe->filename[0]
|
||
&& STREQ (filename, maybe->filename))
|
||
{
|
||
/* We found a match. But there might be several source files
|
||
(from different directories) with the same name. */
|
||
if (0 == maybe->found)
|
||
break;
|
||
questionable = maybe; /* Might use it later. */
|
||
}
|
||
}
|
||
|
||
if (maybe == 0 && questionable != 0)
|
||
{
|
||
complain (&stab_info_questionable_complaint, filename);
|
||
maybe = questionable;
|
||
}
|
||
|
||
if (maybe)
|
||
{
|
||
/* Found it! Allocate a new psymtab struct, and fill it in. */
|
||
maybe->found++;
|
||
pst->section_offsets = (struct section_offsets *)
|
||
obstack_alloc (&objfile -> psymbol_obstack,
|
||
sizeof (struct section_offsets) +
|
||
sizeof (pst->section_offsets->offsets) * (SECT_OFF_MAX-1));
|
||
|
||
for (i = 0; i < SECT_OFF_MAX; i++)
|
||
ANOFFSET (pst->section_offsets, i) = maybe->sections[i];
|
||
return;
|
||
}
|
||
|
||
/* We were unable to find any offsets for this file. Complain. */
|
||
if (dbx->stab_section_info) /* If there *is* any info, */
|
||
complain (&stab_info_mismatch_complaint, filename);
|
||
}
|
||
|
||
/* Register that we are able to handle ELF object file formats. */
|
||
|
||
static struct sym_fns elf_sym_fns =
|
||
{
|
||
bfd_target_elf_flavour,
|
||
elf_new_init, /* sym_new_init: init anything gbl to entire symtab */
|
||
elf_symfile_init, /* sym_init: read initial info, setup for sym_read() */
|
||
elf_symfile_read, /* sym_read: read a symbol file into symtab */
|
||
elf_symfile_finish, /* sym_finish: finished with file, cleanup */
|
||
default_symfile_offsets,
|
||
/* sym_offsets: Translate ext. to int. relocation */
|
||
NULL /* next: pointer to next struct sym_fns */
|
||
};
|
||
|
||
void
|
||
_initialize_elfread ()
|
||
{
|
||
add_symtab_fns (&elf_sym_fns);
|
||
}
|