5543870269
invalid section group.
1793 lines
53 KiB
C++
1793 lines
53 KiB
C++
// object.cc -- support for an object file for linking in gold
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// Copyright 2006, 2007, 2008 Free Software Foundation, Inc.
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// Written by Ian Lance Taylor <iant@google.com>.
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// This file is part of gold.
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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 3 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., 51 Franklin Street - Fifth Floor, Boston,
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// MA 02110-1301, USA.
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#include "gold.h"
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#include <cerrno>
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#include <cstring>
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#include <cstdarg>
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#include "demangle.h"
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#include "libiberty.h"
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#include "target-select.h"
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#include "dwarf_reader.h"
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#include "layout.h"
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#include "output.h"
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#include "symtab.h"
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#include "reloc.h"
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#include "object.h"
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#include "dynobj.h"
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namespace gold
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{
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// Class Xindex.
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// Initialize the symtab_xindex_ array. Find the SHT_SYMTAB_SHNDX
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// section and read it in. SYMTAB_SHNDX is the index of the symbol
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// table we care about.
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template<int size, bool big_endian>
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void
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Xindex::initialize_symtab_xindex(Object* object, unsigned int symtab_shndx)
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{
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if (!this->symtab_xindex_.empty())
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return;
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gold_assert(symtab_shndx != 0);
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// Look through the sections in reverse order, on the theory that it
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// is more likely to be near the end than the beginning.
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unsigned int i = object->shnum();
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while (i > 0)
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{
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--i;
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if (object->section_type(i) == elfcpp::SHT_SYMTAB_SHNDX
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&& this->adjust_shndx(object->section_link(i)) == symtab_shndx)
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{
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this->read_symtab_xindex<size, big_endian>(object, i, NULL);
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return;
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}
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}
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object->error(_("missing SHT_SYMTAB_SHNDX section"));
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}
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// Read in the symtab_xindex_ array, given the section index of the
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// SHT_SYMTAB_SHNDX section. If PSHDRS is not NULL, it points at the
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// section headers.
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template<int size, bool big_endian>
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void
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Xindex::read_symtab_xindex(Object* object, unsigned int xindex_shndx,
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const unsigned char* pshdrs)
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{
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section_size_type bytecount;
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const unsigned char* contents;
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if (pshdrs == NULL)
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contents = object->section_contents(xindex_shndx, &bytecount, false);
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else
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{
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const unsigned char* p = (pshdrs
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+ (xindex_shndx
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* elfcpp::Elf_sizes<size>::shdr_size));
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typename elfcpp::Shdr<size, big_endian> shdr(p);
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bytecount = convert_to_section_size_type(shdr.get_sh_size());
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contents = object->get_view(shdr.get_sh_offset(), bytecount, true, false);
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}
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gold_assert(this->symtab_xindex_.empty());
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this->symtab_xindex_.reserve(bytecount / 4);
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for (section_size_type i = 0; i < bytecount; i += 4)
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{
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unsigned int shndx = elfcpp::Swap<32, big_endian>::readval(contents + i);
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// We preadjust the section indexes we save.
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this->symtab_xindex_.push_back(this->adjust_shndx(shndx));
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}
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}
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// Symbol symndx has a section of SHN_XINDEX; return the real section
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// index.
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unsigned int
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Xindex::sym_xindex_to_shndx(Object* object, unsigned int symndx)
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{
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if (symndx >= this->symtab_xindex_.size())
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{
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object->error(_("symbol %u out of range for SHT_SYMTAB_SHNDX section"),
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symndx);
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return elfcpp::SHN_UNDEF;
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}
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unsigned int shndx = this->symtab_xindex_[symndx];
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if (shndx < elfcpp::SHN_LORESERVE || shndx >= object->shnum())
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{
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object->error(_("extended index for symbol %u out of range: %u"),
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symndx, shndx);
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return elfcpp::SHN_UNDEF;
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}
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return shndx;
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}
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// Class Object.
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// Set the target based on fields in the ELF file header.
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void
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Object::set_target(int machine, int size, bool big_endian, int osabi,
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int abiversion)
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{
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Target* target = select_target(machine, size, big_endian, osabi, abiversion);
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if (target == NULL)
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gold_fatal(_("%s: unsupported ELF machine number %d"),
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this->name().c_str(), machine);
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this->target_ = target;
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}
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// Report an error for this object file. This is used by the
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// elfcpp::Elf_file interface, and also called by the Object code
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// itself.
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void
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Object::error(const char* format, ...) const
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{
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va_list args;
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va_start(args, format);
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char* buf = NULL;
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if (vasprintf(&buf, format, args) < 0)
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gold_nomem();
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va_end(args);
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gold_error(_("%s: %s"), this->name().c_str(), buf);
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free(buf);
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}
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// Return a view of the contents of a section.
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const unsigned char*
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Object::section_contents(unsigned int shndx, section_size_type* plen,
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bool cache)
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{
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Location loc(this->do_section_contents(shndx));
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*plen = convert_to_section_size_type(loc.data_size);
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return this->get_view(loc.file_offset, *plen, true, cache);
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}
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// Read the section data into SD. This is code common to Sized_relobj
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// and Sized_dynobj, so we put it into Object.
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template<int size, bool big_endian>
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void
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Object::read_section_data(elfcpp::Elf_file<size, big_endian, Object>* elf_file,
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Read_symbols_data* sd)
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{
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const int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
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// Read the section headers.
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const off_t shoff = elf_file->shoff();
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const unsigned int shnum = this->shnum();
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sd->section_headers = this->get_lasting_view(shoff, shnum * shdr_size,
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true, true);
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// Read the section names.
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const unsigned char* pshdrs = sd->section_headers->data();
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const unsigned char* pshdrnames = pshdrs + elf_file->shstrndx() * shdr_size;
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typename elfcpp::Shdr<size, big_endian> shdrnames(pshdrnames);
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if (shdrnames.get_sh_type() != elfcpp::SHT_STRTAB)
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this->error(_("section name section has wrong type: %u"),
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static_cast<unsigned int>(shdrnames.get_sh_type()));
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sd->section_names_size =
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convert_to_section_size_type(shdrnames.get_sh_size());
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sd->section_names = this->get_lasting_view(shdrnames.get_sh_offset(),
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sd->section_names_size, false,
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false);
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}
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// If NAME is the name of a special .gnu.warning section, arrange for
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// the warning to be issued. SHNDX is the section index. Return
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// whether it is a warning section.
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bool
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Object::handle_gnu_warning_section(const char* name, unsigned int shndx,
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Symbol_table* symtab)
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{
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const char warn_prefix[] = ".gnu.warning.";
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const int warn_prefix_len = sizeof warn_prefix - 1;
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if (strncmp(name, warn_prefix, warn_prefix_len) == 0)
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{
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// Read the section contents to get the warning text. It would
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// be nicer if we only did this if we have to actually issue a
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// warning. Unfortunately, warnings are issued as we relocate
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// sections. That means that we can not lock the object then,
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// as we might try to issue the same warning multiple times
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// simultaneously.
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section_size_type len;
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const unsigned char* contents = this->section_contents(shndx, &len,
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false);
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std::string warning(reinterpret_cast<const char*>(contents), len);
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symtab->add_warning(name + warn_prefix_len, this, warning);
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return true;
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}
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return false;
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}
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// Class Sized_relobj.
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template<int size, bool big_endian>
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Sized_relobj<size, big_endian>::Sized_relobj(
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const std::string& name,
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Input_file* input_file,
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off_t offset,
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const elfcpp::Ehdr<size, big_endian>& ehdr)
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: Relobj(name, input_file, offset),
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elf_file_(this, ehdr),
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symtab_shndx_(-1U),
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local_symbol_count_(0),
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output_local_symbol_count_(0),
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output_local_dynsym_count_(0),
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symbols_(),
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local_symbol_offset_(0),
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local_dynsym_offset_(0),
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local_values_(),
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local_got_offsets_(),
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has_eh_frame_(false)
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{
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}
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template<int size, bool big_endian>
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Sized_relobj<size, big_endian>::~Sized_relobj()
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{
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}
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// Set up an object file based on the file header. This sets up the
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// target and reads the section information.
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template<int size, bool big_endian>
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void
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Sized_relobj<size, big_endian>::setup(
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const elfcpp::Ehdr<size, big_endian>& ehdr)
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{
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this->set_target(ehdr.get_e_machine(), size, big_endian,
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ehdr.get_e_ident()[elfcpp::EI_OSABI],
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ehdr.get_e_ident()[elfcpp::EI_ABIVERSION]);
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const unsigned int shnum = this->elf_file_.shnum();
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this->set_shnum(shnum);
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}
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// Find the SHT_SYMTAB section, given the section headers. The ELF
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// standard says that maybe in the future there can be more than one
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// SHT_SYMTAB section. Until somebody figures out how that could
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// work, we assume there is only one.
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template<int size, bool big_endian>
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void
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Sized_relobj<size, big_endian>::find_symtab(const unsigned char* pshdrs)
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{
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const unsigned int shnum = this->shnum();
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this->symtab_shndx_ = 0;
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if (shnum > 0)
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{
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// Look through the sections in reverse order, since gas tends
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// to put the symbol table at the end.
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const unsigned char* p = pshdrs + shnum * This::shdr_size;
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unsigned int i = shnum;
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unsigned int xindex_shndx = 0;
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unsigned int xindex_link = 0;
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while (i > 0)
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{
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--i;
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p -= This::shdr_size;
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typename This::Shdr shdr(p);
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if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB)
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{
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this->symtab_shndx_ = i;
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if (xindex_shndx > 0 && xindex_link == i)
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{
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Xindex* xindex =
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new Xindex(this->elf_file_.large_shndx_offset());
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xindex->read_symtab_xindex<size, big_endian>(this,
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xindex_shndx,
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pshdrs);
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this->set_xindex(xindex);
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}
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break;
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}
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// Try to pick up the SHT_SYMTAB_SHNDX section, if there is
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// one. This will work if it follows the SHT_SYMTAB
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// section.
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if (shdr.get_sh_type() == elfcpp::SHT_SYMTAB_SHNDX)
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{
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xindex_shndx = i;
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xindex_link = this->adjust_shndx(shdr.get_sh_link());
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}
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}
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}
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}
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// Return the Xindex structure to use for object with lots of
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// sections.
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template<int size, bool big_endian>
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Xindex*
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Sized_relobj<size, big_endian>::do_initialize_xindex()
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{
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gold_assert(this->symtab_shndx_ != -1U);
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Xindex* xindex = new Xindex(this->elf_file_.large_shndx_offset());
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xindex->initialize_symtab_xindex<size, big_endian>(this, this->symtab_shndx_);
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return xindex;
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}
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// Return whether SHDR has the right type and flags to be a GNU
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// .eh_frame section.
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template<int size, bool big_endian>
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bool
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Sized_relobj<size, big_endian>::check_eh_frame_flags(
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const elfcpp::Shdr<size, big_endian>* shdr) const
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{
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return (shdr->get_sh_type() == elfcpp::SHT_PROGBITS
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&& (shdr->get_sh_flags() & elfcpp::SHF_ALLOC) != 0);
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}
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// Return whether there is a GNU .eh_frame section, given the section
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// headers and the section names.
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template<int size, bool big_endian>
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bool
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Sized_relobj<size, big_endian>::find_eh_frame(
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const unsigned char* pshdrs,
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const char* names,
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section_size_type names_size) const
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{
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const unsigned int shnum = this->shnum();
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const unsigned char* p = pshdrs + This::shdr_size;
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for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size)
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{
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typename This::Shdr shdr(p);
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if (this->check_eh_frame_flags(&shdr))
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{
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if (shdr.get_sh_name() >= names_size)
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{
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this->error(_("bad section name offset for section %u: %lu"),
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i, static_cast<unsigned long>(shdr.get_sh_name()));
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continue;
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}
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const char* name = names + shdr.get_sh_name();
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if (strcmp(name, ".eh_frame") == 0)
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return true;
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}
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}
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return false;
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}
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// Read the sections and symbols from an object file.
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template<int size, bool big_endian>
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void
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Sized_relobj<size, big_endian>::do_read_symbols(Read_symbols_data* sd)
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{
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this->read_section_data(&this->elf_file_, sd);
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const unsigned char* const pshdrs = sd->section_headers->data();
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this->find_symtab(pshdrs);
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const unsigned char* namesu = sd->section_names->data();
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const char* names = reinterpret_cast<const char*>(namesu);
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if (memmem(names, sd->section_names_size, ".eh_frame", 10) != NULL)
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{
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if (this->find_eh_frame(pshdrs, names, sd->section_names_size))
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this->has_eh_frame_ = true;
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}
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sd->symbols = NULL;
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sd->symbols_size = 0;
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sd->external_symbols_offset = 0;
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sd->symbol_names = NULL;
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sd->symbol_names_size = 0;
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if (this->symtab_shndx_ == 0)
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{
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// No symbol table. Weird but legal.
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return;
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}
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// Get the symbol table section header.
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typename This::Shdr symtabshdr(pshdrs
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+ this->symtab_shndx_ * This::shdr_size);
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gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
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// If this object has a .eh_frame section, we need all the symbols.
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// Otherwise we only need the external symbols. While it would be
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// simpler to just always read all the symbols, I've seen object
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// files with well over 2000 local symbols, which for a 64-bit
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// object file format is over 5 pages that we don't need to read
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// now.
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const int sym_size = This::sym_size;
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const unsigned int loccount = symtabshdr.get_sh_info();
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this->local_symbol_count_ = loccount;
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this->local_values_.resize(loccount);
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section_offset_type locsize = loccount * sym_size;
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off_t dataoff = symtabshdr.get_sh_offset();
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section_size_type datasize =
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convert_to_section_size_type(symtabshdr.get_sh_size());
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off_t extoff = dataoff + locsize;
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section_size_type extsize = datasize - locsize;
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off_t readoff = this->has_eh_frame_ ? dataoff : extoff;
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section_size_type readsize = this->has_eh_frame_ ? datasize : extsize;
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File_view* fvsymtab = this->get_lasting_view(readoff, readsize, true, false);
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// Read the section header for the symbol names.
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unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
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if (strtab_shndx >= this->shnum())
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{
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this->error(_("invalid symbol table name index: %u"), strtab_shndx);
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return;
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}
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typename This::Shdr strtabshdr(pshdrs + strtab_shndx * This::shdr_size);
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if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
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{
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this->error(_("symbol table name section has wrong type: %u"),
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static_cast<unsigned int>(strtabshdr.get_sh_type()));
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return;
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}
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// Read the symbol names.
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File_view* fvstrtab = this->get_lasting_view(strtabshdr.get_sh_offset(),
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strtabshdr.get_sh_size(),
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false, true);
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sd->symbols = fvsymtab;
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sd->symbols_size = readsize;
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sd->external_symbols_offset = this->has_eh_frame_ ? locsize : 0;
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sd->symbol_names = fvstrtab;
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sd->symbol_names_size =
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convert_to_section_size_type(strtabshdr.get_sh_size());
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}
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// Return the section index of symbol SYM. Set *VALUE to its value in
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// the object file. Set *IS_ORDINARY if this is an ordinary section
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// index. not a special cod between SHN_LORESERVE and SHN_HIRESERVE.
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// Note that for a symbol which is not defined in this object file,
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// this will set *VALUE to 0 and return SHN_UNDEF; it will not return
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// the final value of the symbol in the link.
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template<int size, bool big_endian>
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unsigned int
|
|
Sized_relobj<size, big_endian>::symbol_section_and_value(unsigned int sym,
|
|
Address* value,
|
|
bool* is_ordinary)
|
|
{
|
|
section_size_type symbols_size;
|
|
const unsigned char* symbols = this->section_contents(this->symtab_shndx_,
|
|
&symbols_size,
|
|
false);
|
|
|
|
const size_t count = symbols_size / This::sym_size;
|
|
gold_assert(sym < count);
|
|
|
|
elfcpp::Sym<size, big_endian> elfsym(symbols + sym * This::sym_size);
|
|
*value = elfsym.get_st_value();
|
|
|
|
return this->adjust_sym_shndx(sym, elfsym.get_st_shndx(), is_ordinary);
|
|
}
|
|
|
|
// Return whether to include a section group in the link. LAYOUT is
|
|
// used to keep track of which section groups we have already seen.
|
|
// INDEX is the index of the section group and SHDR is the section
|
|
// header. If we do not want to include this group, we set bits in
|
|
// OMIT for each section which should be discarded.
|
|
|
|
template<int size, bool big_endian>
|
|
bool
|
|
Sized_relobj<size, big_endian>::include_section_group(
|
|
Symbol_table* symtab,
|
|
Layout* layout,
|
|
unsigned int index,
|
|
const char* name,
|
|
const elfcpp::Shdr<size, big_endian>& shdr,
|
|
std::vector<bool>* omit)
|
|
{
|
|
// Read the section contents.
|
|
const unsigned char* pcon = this->get_view(shdr.get_sh_offset(),
|
|
shdr.get_sh_size(), true, false);
|
|
const elfcpp::Elf_Word* pword =
|
|
reinterpret_cast<const elfcpp::Elf_Word*>(pcon);
|
|
|
|
// The first word contains flags. We only care about COMDAT section
|
|
// groups. Other section groups are always included in the link
|
|
// just like ordinary sections.
|
|
elfcpp::Elf_Word flags = elfcpp::Swap<32, big_endian>::readval(pword);
|
|
|
|
// Look up the group signature, which is the name of a symbol. This
|
|
// is a lot of effort to go to to read a string. Why didn't they
|
|
// just have the group signature point into the string table, rather
|
|
// than indirect through a symbol?
|
|
|
|
// Get the appropriate symbol table header (this will normally be
|
|
// the single SHT_SYMTAB section, but in principle it need not be).
|
|
const unsigned int link = this->adjust_shndx(shdr.get_sh_link());
|
|
typename This::Shdr symshdr(this, this->elf_file_.section_header(link));
|
|
|
|
// Read the symbol table entry.
|
|
unsigned int symndx = shdr.get_sh_info();
|
|
if (symndx >= symshdr.get_sh_size() / This::sym_size)
|
|
{
|
|
this->error(_("section group %u info %u out of range"),
|
|
index, symndx);
|
|
return false;
|
|
}
|
|
off_t symoff = symshdr.get_sh_offset() + symndx * This::sym_size;
|
|
const unsigned char* psym = this->get_view(symoff, This::sym_size, true,
|
|
false);
|
|
elfcpp::Sym<size, big_endian> sym(psym);
|
|
|
|
// Read the symbol table names.
|
|
section_size_type symnamelen;
|
|
const unsigned char* psymnamesu;
|
|
psymnamesu = this->section_contents(this->adjust_shndx(symshdr.get_sh_link()),
|
|
&symnamelen, true);
|
|
const char* psymnames = reinterpret_cast<const char*>(psymnamesu);
|
|
|
|
// Get the section group signature.
|
|
if (sym.get_st_name() >= symnamelen)
|
|
{
|
|
this->error(_("symbol %u name offset %u out of range"),
|
|
symndx, sym.get_st_name());
|
|
return false;
|
|
}
|
|
|
|
const char* signature = psymnames + sym.get_st_name();
|
|
|
|
// It seems that some versions of gas will create a section group
|
|
// associated with a section symbol, and then fail to give a name to
|
|
// the section symbol. In such a case, use the name of the section.
|
|
std::string secname;
|
|
if (signature[0] == '\0' && sym.get_st_type() == elfcpp::STT_SECTION)
|
|
{
|
|
bool is_ordinary;
|
|
unsigned int sym_shndx = this->adjust_sym_shndx(symndx,
|
|
sym.get_st_shndx(),
|
|
&is_ordinary);
|
|
if (!is_ordinary || sym_shndx >= this->shnum())
|
|
{
|
|
this->error(_("symbol %u invalid section index %u"),
|
|
symndx, sym_shndx);
|
|
return false;
|
|
}
|
|
secname = this->section_name(sym_shndx);
|
|
signature = secname.c_str();
|
|
}
|
|
|
|
// Record this section group, and see whether we've already seen one
|
|
// with the same signature.
|
|
|
|
if ((flags & elfcpp::GRP_COMDAT) == 0
|
|
|| layout->add_comdat(signature, true))
|
|
{
|
|
if (parameters->options().relocatable())
|
|
layout->layout_group(symtab, this, index, name, signature, shdr,
|
|
pword);
|
|
return true;
|
|
}
|
|
|
|
// This is a duplicate. We want to discard the sections in this
|
|
// group.
|
|
size_t count = shdr.get_sh_size() / sizeof(elfcpp::Elf_Word);
|
|
for (size_t i = 1; i < count; ++i)
|
|
{
|
|
elfcpp::Elf_Word secnum =
|
|
elfcpp::Swap<32, big_endian>::readval(pword + i);
|
|
if (secnum >= this->shnum())
|
|
{
|
|
this->error(_("section %u in section group %u out of range"),
|
|
secnum, index);
|
|
continue;
|
|
}
|
|
|
|
// Check for an earlier section number, since we're going to get
|
|
// it wrong--we may have already decided to include the section.
|
|
if (secnum < index)
|
|
this->error(_("invalid section group %u refers to earlier section %u"),
|
|
index, secnum);
|
|
|
|
(*omit)[secnum] = true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
// Whether to include a linkonce section in the link. NAME is the
|
|
// name of the section and SHDR is the section header.
|
|
|
|
// Linkonce sections are a GNU extension implemented in the original
|
|
// GNU linker before section groups were defined. The semantics are
|
|
// that we only include one linkonce section with a given name. The
|
|
// name of a linkonce section is normally .gnu.linkonce.T.SYMNAME,
|
|
// where T is the type of section and SYMNAME is the name of a symbol.
|
|
// In an attempt to make linkonce sections interact well with section
|
|
// groups, we try to identify SYMNAME and use it like a section group
|
|
// signature. We want to block section groups with that signature,
|
|
// but not other linkonce sections with that signature. We also use
|
|
// the full name of the linkonce section as a normal section group
|
|
// signature.
|
|
|
|
template<int size, bool big_endian>
|
|
bool
|
|
Sized_relobj<size, big_endian>::include_linkonce_section(
|
|
Layout* layout,
|
|
const char* name,
|
|
const elfcpp::Shdr<size, big_endian>&)
|
|
{
|
|
// In general the symbol name we want will be the string following
|
|
// the last '.'. However, we have to handle the case of
|
|
// .gnu.linkonce.t.__i686.get_pc_thunk.bx, which was generated by
|
|
// some versions of gcc. So we use a heuristic: if the name starts
|
|
// with ".gnu.linkonce.t.", we use everything after that. Otherwise
|
|
// we look for the last '.'. We can't always simply skip
|
|
// ".gnu.linkonce.X", because we have to deal with cases like
|
|
// ".gnu.linkonce.d.rel.ro.local".
|
|
const char* const linkonce_t = ".gnu.linkonce.t.";
|
|
const char* symname;
|
|
if (strncmp(name, linkonce_t, strlen(linkonce_t)) == 0)
|
|
symname = name + strlen(linkonce_t);
|
|
else
|
|
symname = strrchr(name, '.') + 1;
|
|
bool include1 = layout->add_comdat(symname, false);
|
|
bool include2 = layout->add_comdat(name, true);
|
|
return include1 && include2;
|
|
}
|
|
|
|
// Lay out the input sections. We walk through the sections and check
|
|
// whether they should be included in the link. If they should, we
|
|
// pass them to the Layout object, which will return an output section
|
|
// and an offset.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj<size, big_endian>::do_layout(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_symbols_data* sd)
|
|
{
|
|
const unsigned int shnum = this->shnum();
|
|
if (shnum == 0)
|
|
return;
|
|
|
|
// Get the section headers.
|
|
const unsigned char* pshdrs = sd->section_headers->data();
|
|
|
|
// Get the section names.
|
|
const unsigned char* pnamesu = sd->section_names->data();
|
|
const char* pnames = reinterpret_cast<const char*>(pnamesu);
|
|
|
|
// For each section, record the index of the reloc section if any.
|
|
// Use 0 to mean that there is no reloc section, -1U to mean that
|
|
// there is more than one.
|
|
std::vector<unsigned int> reloc_shndx(shnum, 0);
|
|
std::vector<unsigned int> reloc_type(shnum, elfcpp::SHT_NULL);
|
|
// Skip the first, dummy, section.
|
|
pshdrs += This::shdr_size;
|
|
for (unsigned int i = 1; i < shnum; ++i, pshdrs += This::shdr_size)
|
|
{
|
|
typename This::Shdr shdr(pshdrs);
|
|
|
|
unsigned int sh_type = shdr.get_sh_type();
|
|
if (sh_type == elfcpp::SHT_REL || sh_type == elfcpp::SHT_RELA)
|
|
{
|
|
unsigned int target_shndx = this->adjust_shndx(shdr.get_sh_info());
|
|
if (target_shndx == 0 || target_shndx >= shnum)
|
|
{
|
|
this->error(_("relocation section %u has bad info %u"),
|
|
i, target_shndx);
|
|
continue;
|
|
}
|
|
|
|
if (reloc_shndx[target_shndx] != 0)
|
|
reloc_shndx[target_shndx] = -1U;
|
|
else
|
|
{
|
|
reloc_shndx[target_shndx] = i;
|
|
reloc_type[target_shndx] = sh_type;
|
|
}
|
|
}
|
|
}
|
|
|
|
std::vector<Map_to_output>& map_sections(this->map_to_output());
|
|
map_sections.resize(shnum);
|
|
|
|
// If we are only linking for symbols, then there is nothing else to
|
|
// do here.
|
|
if (this->input_file()->just_symbols())
|
|
{
|
|
delete sd->section_headers;
|
|
sd->section_headers = NULL;
|
|
delete sd->section_names;
|
|
sd->section_names = NULL;
|
|
return;
|
|
}
|
|
|
|
// Whether we've seen a .note.GNU-stack section.
|
|
bool seen_gnu_stack = false;
|
|
// The flags of a .note.GNU-stack section.
|
|
uint64_t gnu_stack_flags = 0;
|
|
|
|
// Keep track of which sections to omit.
|
|
std::vector<bool> omit(shnum, false);
|
|
|
|
// Keep track of reloc sections when emitting relocations.
|
|
const bool relocatable = parameters->options().relocatable();
|
|
const bool emit_relocs = (relocatable
|
|
|| parameters->options().emit_relocs());
|
|
std::vector<unsigned int> reloc_sections;
|
|
|
|
// Keep track of .eh_frame sections.
|
|
std::vector<unsigned int> eh_frame_sections;
|
|
|
|
// Skip the first, dummy, section.
|
|
pshdrs = sd->section_headers->data() + This::shdr_size;
|
|
for (unsigned int i = 1; i < shnum; ++i, pshdrs += This::shdr_size)
|
|
{
|
|
typename This::Shdr shdr(pshdrs);
|
|
|
|
if (shdr.get_sh_name() >= sd->section_names_size)
|
|
{
|
|
this->error(_("bad section name offset for section %u: %lu"),
|
|
i, static_cast<unsigned long>(shdr.get_sh_name()));
|
|
return;
|
|
}
|
|
|
|
const char* name = pnames + shdr.get_sh_name();
|
|
|
|
if (this->handle_gnu_warning_section(name, i, symtab))
|
|
{
|
|
if (!relocatable)
|
|
omit[i] = true;
|
|
}
|
|
|
|
// The .note.GNU-stack section is special. It gives the
|
|
// protection flags that this object file requires for the stack
|
|
// in memory.
|
|
if (strcmp(name, ".note.GNU-stack") == 0)
|
|
{
|
|
seen_gnu_stack = true;
|
|
gnu_stack_flags |= shdr.get_sh_flags();
|
|
omit[i] = true;
|
|
}
|
|
|
|
bool discard = omit[i];
|
|
if (!discard)
|
|
{
|
|
if (shdr.get_sh_type() == elfcpp::SHT_GROUP)
|
|
{
|
|
if (!this->include_section_group(symtab, layout, i, name, shdr,
|
|
&omit))
|
|
discard = true;
|
|
}
|
|
else if ((shdr.get_sh_flags() & elfcpp::SHF_GROUP) == 0
|
|
&& Layout::is_linkonce(name))
|
|
{
|
|
if (!this->include_linkonce_section(layout, name, shdr))
|
|
discard = true;
|
|
}
|
|
}
|
|
|
|
if (discard)
|
|
{
|
|
// Do not include this section in the link.
|
|
map_sections[i].output_section = NULL;
|
|
continue;
|
|
}
|
|
|
|
// When doing a relocatable link we are going to copy input
|
|
// reloc sections into the output. We only want to copy the
|
|
// ones associated with sections which are not being discarded.
|
|
// However, we don't know that yet for all sections. So save
|
|
// reloc sections and process them later.
|
|
if (emit_relocs
|
|
&& (shdr.get_sh_type() == elfcpp::SHT_REL
|
|
|| shdr.get_sh_type() == elfcpp::SHT_RELA))
|
|
{
|
|
reloc_sections.push_back(i);
|
|
continue;
|
|
}
|
|
|
|
if (relocatable && shdr.get_sh_type() == elfcpp::SHT_GROUP)
|
|
continue;
|
|
|
|
// The .eh_frame section is special. It holds exception frame
|
|
// information that we need to read in order to generate the
|
|
// exception frame header. We process these after all the other
|
|
// sections so that the exception frame reader can reliably
|
|
// determine which sections are being discarded, and discard the
|
|
// corresponding information.
|
|
if (!relocatable
|
|
&& strcmp(name, ".eh_frame") == 0
|
|
&& this->check_eh_frame_flags(&shdr))
|
|
{
|
|
eh_frame_sections.push_back(i);
|
|
continue;
|
|
}
|
|
|
|
off_t offset;
|
|
Output_section* os = layout->layout(this, i, name, shdr,
|
|
reloc_shndx[i], reloc_type[i],
|
|
&offset);
|
|
|
|
map_sections[i].output_section = os;
|
|
map_sections[i].offset = offset;
|
|
|
|
// If this section requires special handling, and if there are
|
|
// relocs that apply to it, then we must do the special handling
|
|
// before we apply the relocs.
|
|
if (offset == -1 && reloc_shndx[i] != 0)
|
|
this->set_relocs_must_follow_section_writes();
|
|
}
|
|
|
|
layout->layout_gnu_stack(seen_gnu_stack, gnu_stack_flags);
|
|
|
|
// When doing a relocatable link handle the reloc sections at the
|
|
// end.
|
|
if (emit_relocs)
|
|
this->size_relocatable_relocs();
|
|
for (std::vector<unsigned int>::const_iterator p = reloc_sections.begin();
|
|
p != reloc_sections.end();
|
|
++p)
|
|
{
|
|
unsigned int i = *p;
|
|
const unsigned char* pshdr;
|
|
pshdr = sd->section_headers->data() + i * This::shdr_size;
|
|
typename This::Shdr shdr(pshdr);
|
|
|
|
unsigned int data_shndx = this->adjust_shndx(shdr.get_sh_info());
|
|
if (data_shndx >= shnum)
|
|
{
|
|
// We already warned about this above.
|
|
continue;
|
|
}
|
|
|
|
Output_section* data_section = map_sections[data_shndx].output_section;
|
|
if (data_section == NULL)
|
|
{
|
|
map_sections[i].output_section = NULL;
|
|
continue;
|
|
}
|
|
|
|
Relocatable_relocs* rr = new Relocatable_relocs();
|
|
this->set_relocatable_relocs(i, rr);
|
|
|
|
Output_section* os = layout->layout_reloc(this, i, shdr, data_section,
|
|
rr);
|
|
map_sections[i].output_section = os;
|
|
map_sections[i].offset = -1;
|
|
}
|
|
|
|
// Handle the .eh_frame sections at the end.
|
|
for (std::vector<unsigned int>::const_iterator p = eh_frame_sections.begin();
|
|
p != eh_frame_sections.end();
|
|
++p)
|
|
{
|
|
gold_assert(this->has_eh_frame_);
|
|
gold_assert(sd->external_symbols_offset != 0);
|
|
|
|
unsigned int i = *p;
|
|
const unsigned char *pshdr;
|
|
pshdr = sd->section_headers->data() + i * This::shdr_size;
|
|
typename This::Shdr shdr(pshdr);
|
|
|
|
off_t offset;
|
|
Output_section* os = layout->layout_eh_frame(this,
|
|
sd->symbols->data(),
|
|
sd->symbols_size,
|
|
sd->symbol_names->data(),
|
|
sd->symbol_names_size,
|
|
i, shdr,
|
|
reloc_shndx[i],
|
|
reloc_type[i],
|
|
&offset);
|
|
map_sections[i].output_section = os;
|
|
map_sections[i].offset = offset;
|
|
|
|
// If this section requires special handling, and if there are
|
|
// relocs that apply to it, then we must do the special handling
|
|
// before we apply the relocs.
|
|
if (offset == -1 && reloc_shndx[i] != 0)
|
|
this->set_relocs_must_follow_section_writes();
|
|
}
|
|
|
|
delete sd->section_headers;
|
|
sd->section_headers = NULL;
|
|
delete sd->section_names;
|
|
sd->section_names = NULL;
|
|
}
|
|
|
|
// Add the symbols to the symbol table.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj<size, big_endian>::do_add_symbols(Symbol_table* symtab,
|
|
Read_symbols_data* sd)
|
|
{
|
|
if (sd->symbols == NULL)
|
|
{
|
|
gold_assert(sd->symbol_names == NULL);
|
|
return;
|
|
}
|
|
|
|
const int sym_size = This::sym_size;
|
|
size_t symcount = ((sd->symbols_size - sd->external_symbols_offset)
|
|
/ sym_size);
|
|
if (symcount * sym_size != sd->symbols_size - sd->external_symbols_offset)
|
|
{
|
|
this->error(_("size of symbols is not multiple of symbol size"));
|
|
return;
|
|
}
|
|
|
|
this->symbols_.resize(symcount);
|
|
|
|
const char* sym_names =
|
|
reinterpret_cast<const char*>(sd->symbol_names->data());
|
|
symtab->add_from_relobj(this,
|
|
sd->symbols->data() + sd->external_symbols_offset,
|
|
symcount, this->local_symbol_count_,
|
|
sym_names, sd->symbol_names_size,
|
|
&this->symbols_);
|
|
|
|
delete sd->symbols;
|
|
sd->symbols = NULL;
|
|
delete sd->symbol_names;
|
|
sd->symbol_names = NULL;
|
|
}
|
|
|
|
// First pass over the local symbols. Here we add their names to
|
|
// *POOL and *DYNPOOL, and we store the symbol value in
|
|
// THIS->LOCAL_VALUES_. This function is always called from a
|
|
// singleton thread. This is followed by a call to
|
|
// finalize_local_symbols.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj<size, big_endian>::do_count_local_symbols(Stringpool* pool,
|
|
Stringpool* dynpool)
|
|
{
|
|
gold_assert(this->symtab_shndx_ != -1U);
|
|
if (this->symtab_shndx_ == 0)
|
|
{
|
|
// This object has no symbols. Weird but legal.
|
|
return;
|
|
}
|
|
|
|
// Read the symbol table section header.
|
|
const unsigned int symtab_shndx = this->symtab_shndx_;
|
|
typename This::Shdr symtabshdr(this,
|
|
this->elf_file_.section_header(symtab_shndx));
|
|
gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
|
|
|
|
// Read the local symbols.
|
|
const int sym_size = This::sym_size;
|
|
const unsigned int loccount = this->local_symbol_count_;
|
|
gold_assert(loccount == symtabshdr.get_sh_info());
|
|
off_t locsize = loccount * sym_size;
|
|
const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
|
|
locsize, true, true);
|
|
|
|
// Read the symbol names.
|
|
const unsigned int strtab_shndx =
|
|
this->adjust_shndx(symtabshdr.get_sh_link());
|
|
section_size_type strtab_size;
|
|
const unsigned char* pnamesu = this->section_contents(strtab_shndx,
|
|
&strtab_size,
|
|
true);
|
|
const char* pnames = reinterpret_cast<const char*>(pnamesu);
|
|
|
|
// Loop over the local symbols.
|
|
|
|
const std::vector<Map_to_output>& mo(this->map_to_output());
|
|
unsigned int shnum = this->shnum();
|
|
unsigned int count = 0;
|
|
unsigned int dyncount = 0;
|
|
// Skip the first, dummy, symbol.
|
|
psyms += sym_size;
|
|
for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
|
|
{
|
|
elfcpp::Sym<size, big_endian> sym(psyms);
|
|
|
|
Symbol_value<size>& lv(this->local_values_[i]);
|
|
|
|
bool is_ordinary;
|
|
unsigned int shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
|
|
&is_ordinary);
|
|
lv.set_input_shndx(shndx, is_ordinary);
|
|
|
|
if (sym.get_st_type() == elfcpp::STT_SECTION)
|
|
lv.set_is_section_symbol();
|
|
else if (sym.get_st_type() == elfcpp::STT_TLS)
|
|
lv.set_is_tls_symbol();
|
|
|
|
// Save the input symbol value for use in do_finalize_local_symbols().
|
|
lv.set_input_value(sym.get_st_value());
|
|
|
|
// Decide whether this symbol should go into the output file.
|
|
|
|
if (shndx < shnum && mo[shndx].output_section == NULL)
|
|
{
|
|
lv.set_no_output_symtab_entry();
|
|
gold_assert(!lv.needs_output_dynsym_entry());
|
|
continue;
|
|
}
|
|
|
|
if (sym.get_st_type() == elfcpp::STT_SECTION)
|
|
{
|
|
lv.set_no_output_symtab_entry();
|
|
gold_assert(!lv.needs_output_dynsym_entry());
|
|
continue;
|
|
}
|
|
|
|
if (sym.get_st_name() >= strtab_size)
|
|
{
|
|
this->error(_("local symbol %u section name out of range: %u >= %u"),
|
|
i, sym.get_st_name(),
|
|
static_cast<unsigned int>(strtab_size));
|
|
lv.set_no_output_symtab_entry();
|
|
continue;
|
|
}
|
|
|
|
// Add the symbol to the symbol table string pool.
|
|
const char* name = pnames + sym.get_st_name();
|
|
pool->add(name, true, NULL);
|
|
++count;
|
|
|
|
// If needed, add the symbol to the dynamic symbol table string pool.
|
|
if (lv.needs_output_dynsym_entry())
|
|
{
|
|
dynpool->add(name, true, NULL);
|
|
++dyncount;
|
|
}
|
|
}
|
|
|
|
this->output_local_symbol_count_ = count;
|
|
this->output_local_dynsym_count_ = dyncount;
|
|
}
|
|
|
|
// Finalize the local symbols. Here we set the final value in
|
|
// THIS->LOCAL_VALUES_ and set their output symbol table indexes.
|
|
// This function is always called from a singleton thread. The actual
|
|
// output of the local symbols will occur in a separate task.
|
|
|
|
template<int size, bool big_endian>
|
|
unsigned int
|
|
Sized_relobj<size, big_endian>::do_finalize_local_symbols(unsigned int index,
|
|
off_t off)
|
|
{
|
|
gold_assert(off == static_cast<off_t>(align_address(off, size >> 3)));
|
|
|
|
const unsigned int loccount = this->local_symbol_count_;
|
|
this->local_symbol_offset_ = off;
|
|
|
|
const std::vector<Map_to_output>& mo(this->map_to_output());
|
|
unsigned int shnum = this->shnum();
|
|
|
|
for (unsigned int i = 1; i < loccount; ++i)
|
|
{
|
|
Symbol_value<size>& lv(this->local_values_[i]);
|
|
|
|
bool is_ordinary;
|
|
unsigned int shndx = lv.input_shndx(&is_ordinary);
|
|
|
|
// Set the output symbol value.
|
|
|
|
if (!is_ordinary)
|
|
{
|
|
if (shndx == elfcpp::SHN_ABS || shndx == elfcpp::SHN_COMMON)
|
|
lv.set_output_value(lv.input_value());
|
|
else
|
|
{
|
|
this->error(_("unknown section index %u for local symbol %u"),
|
|
shndx, i);
|
|
lv.set_output_value(0);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (shndx >= shnum)
|
|
{
|
|
this->error(_("local symbol %u section index %u out of range"),
|
|
i, shndx);
|
|
shndx = 0;
|
|
}
|
|
|
|
Output_section* os = mo[shndx].output_section;
|
|
|
|
if (os == NULL)
|
|
{
|
|
lv.set_output_value(0);
|
|
continue;
|
|
}
|
|
else if (mo[shndx].offset == -1)
|
|
{
|
|
// This is a SHF_MERGE section or one which otherwise
|
|
// requires special handling. We get the output address
|
|
// of the start of the merged section. If this is not a
|
|
// section symbol, we can then determine the final
|
|
// value. If it is a section symbol, we can not, as in
|
|
// that case we have to consider the addend to determine
|
|
// the value to use in a relocation.
|
|
if (!lv.is_section_symbol())
|
|
lv.set_output_value(os->output_address(this, shndx,
|
|
lv.input_value()));
|
|
else
|
|
{
|
|
section_offset_type start =
|
|
os->starting_output_address(this, shndx);
|
|
Merged_symbol_value<size>* msv =
|
|
new Merged_symbol_value<size>(lv.input_value(), start);
|
|
lv.set_merged_symbol_value(msv);
|
|
}
|
|
}
|
|
else if (lv.is_tls_symbol())
|
|
lv.set_output_value(os->tls_offset()
|
|
+ mo[shndx].offset
|
|
+ lv.input_value());
|
|
else
|
|
lv.set_output_value(os->address()
|
|
+ mo[shndx].offset
|
|
+ lv.input_value());
|
|
}
|
|
|
|
if (lv.needs_output_symtab_entry())
|
|
{
|
|
lv.set_output_symtab_index(index);
|
|
++index;
|
|
}
|
|
}
|
|
return index;
|
|
}
|
|
|
|
// Set the output dynamic symbol table indexes for the local variables.
|
|
|
|
template<int size, bool big_endian>
|
|
unsigned int
|
|
Sized_relobj<size, big_endian>::do_set_local_dynsym_indexes(unsigned int index)
|
|
{
|
|
const unsigned int loccount = this->local_symbol_count_;
|
|
for (unsigned int i = 1; i < loccount; ++i)
|
|
{
|
|
Symbol_value<size>& lv(this->local_values_[i]);
|
|
if (lv.needs_output_dynsym_entry())
|
|
{
|
|
lv.set_output_dynsym_index(index);
|
|
++index;
|
|
}
|
|
}
|
|
return index;
|
|
}
|
|
|
|
// Set the offset where local dynamic symbol information will be stored.
|
|
// Returns the count of local symbols contributed to the symbol table by
|
|
// this object.
|
|
|
|
template<int size, bool big_endian>
|
|
unsigned int
|
|
Sized_relobj<size, big_endian>::do_set_local_dynsym_offset(off_t off)
|
|
{
|
|
gold_assert(off == static_cast<off_t>(align_address(off, size >> 3)));
|
|
this->local_dynsym_offset_ = off;
|
|
return this->output_local_dynsym_count_;
|
|
}
|
|
|
|
// Write out the local symbols.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj<size, big_endian>::write_local_symbols(
|
|
Output_file* of,
|
|
const Stringpool* sympool,
|
|
const Stringpool* dynpool,
|
|
Output_symtab_xindex* symtab_xindex,
|
|
Output_symtab_xindex* dynsym_xindex)
|
|
{
|
|
if (parameters->options().strip_all()
|
|
&& this->output_local_dynsym_count_ == 0)
|
|
return;
|
|
|
|
gold_assert(this->symtab_shndx_ != -1U);
|
|
if (this->symtab_shndx_ == 0)
|
|
{
|
|
// This object has no symbols. Weird but legal.
|
|
return;
|
|
}
|
|
|
|
// Read the symbol table section header.
|
|
const unsigned int symtab_shndx = this->symtab_shndx_;
|
|
typename This::Shdr symtabshdr(this,
|
|
this->elf_file_.section_header(symtab_shndx));
|
|
gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
|
|
const unsigned int loccount = this->local_symbol_count_;
|
|
gold_assert(loccount == symtabshdr.get_sh_info());
|
|
|
|
// Read the local symbols.
|
|
const int sym_size = This::sym_size;
|
|
off_t locsize = loccount * sym_size;
|
|
const unsigned char* psyms = this->get_view(symtabshdr.get_sh_offset(),
|
|
locsize, true, false);
|
|
|
|
// Read the symbol names.
|
|
const unsigned int strtab_shndx =
|
|
this->adjust_shndx(symtabshdr.get_sh_link());
|
|
section_size_type strtab_size;
|
|
const unsigned char* pnamesu = this->section_contents(strtab_shndx,
|
|
&strtab_size,
|
|
false);
|
|
const char* pnames = reinterpret_cast<const char*>(pnamesu);
|
|
|
|
// Get views into the output file for the portions of the symbol table
|
|
// and the dynamic symbol table that we will be writing.
|
|
off_t output_size = this->output_local_symbol_count_ * sym_size;
|
|
unsigned char* oview = NULL;
|
|
if (output_size > 0)
|
|
oview = of->get_output_view(this->local_symbol_offset_, output_size);
|
|
|
|
off_t dyn_output_size = this->output_local_dynsym_count_ * sym_size;
|
|
unsigned char* dyn_oview = NULL;
|
|
if (dyn_output_size > 0)
|
|
dyn_oview = of->get_output_view(this->local_dynsym_offset_,
|
|
dyn_output_size);
|
|
|
|
const std::vector<Map_to_output>& mo(this->map_to_output());
|
|
|
|
gold_assert(this->local_values_.size() == loccount);
|
|
|
|
unsigned char* ov = oview;
|
|
unsigned char* dyn_ov = dyn_oview;
|
|
psyms += sym_size;
|
|
for (unsigned int i = 1; i < loccount; ++i, psyms += sym_size)
|
|
{
|
|
elfcpp::Sym<size, big_endian> isym(psyms);
|
|
|
|
Symbol_value<size>& lv(this->local_values_[i]);
|
|
|
|
bool is_ordinary;
|
|
unsigned int st_shndx = this->adjust_sym_shndx(i, isym.get_st_shndx(),
|
|
&is_ordinary);
|
|
if (is_ordinary)
|
|
{
|
|
gold_assert(st_shndx < mo.size());
|
|
if (mo[st_shndx].output_section == NULL)
|
|
continue;
|
|
st_shndx = mo[st_shndx].output_section->out_shndx();
|
|
if (st_shndx >= elfcpp::SHN_LORESERVE)
|
|
{
|
|
if (lv.needs_output_symtab_entry())
|
|
symtab_xindex->add(lv.output_symtab_index(), st_shndx);
|
|
if (lv.needs_output_dynsym_entry())
|
|
dynsym_xindex->add(lv.output_dynsym_index(), st_shndx);
|
|
st_shndx = elfcpp::SHN_XINDEX;
|
|
}
|
|
}
|
|
|
|
// Write the symbol to the output symbol table.
|
|
if (!parameters->options().strip_all()
|
|
&& lv.needs_output_symtab_entry())
|
|
{
|
|
elfcpp::Sym_write<size, big_endian> osym(ov);
|
|
|
|
gold_assert(isym.get_st_name() < strtab_size);
|
|
const char* name = pnames + isym.get_st_name();
|
|
osym.put_st_name(sympool->get_offset(name));
|
|
osym.put_st_value(this->local_values_[i].value(this, 0));
|
|
osym.put_st_size(isym.get_st_size());
|
|
osym.put_st_info(isym.get_st_info());
|
|
osym.put_st_other(isym.get_st_other());
|
|
osym.put_st_shndx(st_shndx);
|
|
|
|
ov += sym_size;
|
|
}
|
|
|
|
// Write the symbol to the output dynamic symbol table.
|
|
if (lv.needs_output_dynsym_entry())
|
|
{
|
|
gold_assert(dyn_ov < dyn_oview + dyn_output_size);
|
|
elfcpp::Sym_write<size, big_endian> osym(dyn_ov);
|
|
|
|
gold_assert(isym.get_st_name() < strtab_size);
|
|
const char* name = pnames + isym.get_st_name();
|
|
osym.put_st_name(dynpool->get_offset(name));
|
|
osym.put_st_value(this->local_values_[i].value(this, 0));
|
|
osym.put_st_size(isym.get_st_size());
|
|
osym.put_st_info(isym.get_st_info());
|
|
osym.put_st_other(isym.get_st_other());
|
|
osym.put_st_shndx(st_shndx);
|
|
|
|
dyn_ov += sym_size;
|
|
}
|
|
}
|
|
|
|
|
|
if (output_size > 0)
|
|
{
|
|
gold_assert(ov - oview == output_size);
|
|
of->write_output_view(this->local_symbol_offset_, output_size, oview);
|
|
}
|
|
|
|
if (dyn_output_size > 0)
|
|
{
|
|
gold_assert(dyn_ov - dyn_oview == dyn_output_size);
|
|
of->write_output_view(this->local_dynsym_offset_, dyn_output_size,
|
|
dyn_oview);
|
|
}
|
|
}
|
|
|
|
// Set *INFO to symbolic information about the offset OFFSET in the
|
|
// section SHNDX. Return true if we found something, false if we
|
|
// found nothing.
|
|
|
|
template<int size, bool big_endian>
|
|
bool
|
|
Sized_relobj<size, big_endian>::get_symbol_location_info(
|
|
unsigned int shndx,
|
|
off_t offset,
|
|
Symbol_location_info* info)
|
|
{
|
|
if (this->symtab_shndx_ == 0)
|
|
return false;
|
|
|
|
section_size_type symbols_size;
|
|
const unsigned char* symbols = this->section_contents(this->symtab_shndx_,
|
|
&symbols_size,
|
|
false);
|
|
|
|
unsigned int symbol_names_shndx =
|
|
this->adjust_shndx(this->section_link(this->symtab_shndx_));
|
|
section_size_type names_size;
|
|
const unsigned char* symbol_names_u =
|
|
this->section_contents(symbol_names_shndx, &names_size, false);
|
|
const char* symbol_names = reinterpret_cast<const char*>(symbol_names_u);
|
|
|
|
const int sym_size = This::sym_size;
|
|
const size_t count = symbols_size / sym_size;
|
|
|
|
const unsigned char* p = symbols;
|
|
for (size_t i = 0; i < count; ++i, p += sym_size)
|
|
{
|
|
elfcpp::Sym<size, big_endian> sym(p);
|
|
|
|
if (sym.get_st_type() == elfcpp::STT_FILE)
|
|
{
|
|
if (sym.get_st_name() >= names_size)
|
|
info->source_file = "(invalid)";
|
|
else
|
|
info->source_file = symbol_names + sym.get_st_name();
|
|
continue;
|
|
}
|
|
|
|
bool is_ordinary;
|
|
unsigned int st_shndx = this->adjust_sym_shndx(i, sym.get_st_shndx(),
|
|
&is_ordinary);
|
|
if (is_ordinary
|
|
&& st_shndx == shndx
|
|
&& static_cast<off_t>(sym.get_st_value()) <= offset
|
|
&& (static_cast<off_t>(sym.get_st_value() + sym.get_st_size())
|
|
> offset))
|
|
{
|
|
if (sym.get_st_name() > names_size)
|
|
info->enclosing_symbol_name = "(invalid)";
|
|
else
|
|
{
|
|
info->enclosing_symbol_name = symbol_names + sym.get_st_name();
|
|
if (parameters->options().do_demangle())
|
|
{
|
|
char* demangled_name = cplus_demangle(
|
|
info->enclosing_symbol_name.c_str(),
|
|
DMGL_ANSI | DMGL_PARAMS);
|
|
if (demangled_name != NULL)
|
|
{
|
|
info->enclosing_symbol_name.assign(demangled_name);
|
|
free(demangled_name);
|
|
}
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
// Input_objects methods.
|
|
|
|
// Add a regular relocatable object to the list. Return false if this
|
|
// object should be ignored.
|
|
|
|
bool
|
|
Input_objects::add_object(Object* obj)
|
|
{
|
|
// Set the global target from the first object file we recognize.
|
|
Target* target = obj->target();
|
|
if (!parameters->target_valid())
|
|
set_parameters_target(target);
|
|
else if (target != ¶meters->target())
|
|
{
|
|
obj->error(_("incompatible target"));
|
|
return false;
|
|
}
|
|
|
|
// Print the filename if the -t/--trace option is selected.
|
|
if (parameters->options().trace())
|
|
gold_info("%s", obj->name().c_str());
|
|
|
|
if (!obj->is_dynamic())
|
|
this->relobj_list_.push_back(static_cast<Relobj*>(obj));
|
|
else
|
|
{
|
|
// See if this is a duplicate SONAME.
|
|
Dynobj* dynobj = static_cast<Dynobj*>(obj);
|
|
const char* soname = dynobj->soname();
|
|
|
|
std::pair<Unordered_set<std::string>::iterator, bool> ins =
|
|
this->sonames_.insert(soname);
|
|
if (!ins.second)
|
|
{
|
|
// We have already seen a dynamic object with this soname.
|
|
return false;
|
|
}
|
|
|
|
this->dynobj_list_.push_back(dynobj);
|
|
|
|
// If this is -lc, remember the directory in which we found it.
|
|
// We use this when issuing warnings about undefined symbols: as
|
|
// a heuristic, we don't warn about system libraries found in
|
|
// the same directory as -lc.
|
|
if (strncmp(soname, "libc.so", 7) == 0)
|
|
{
|
|
const char* object_name = dynobj->name().c_str();
|
|
const char* base = lbasename(object_name);
|
|
if (base != object_name)
|
|
this->system_library_directory_.assign(object_name,
|
|
base - 1 - object_name);
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
// Return whether an object was found in the system library directory.
|
|
|
|
bool
|
|
Input_objects::found_in_system_library_directory(const Object* object) const
|
|
{
|
|
return (!this->system_library_directory_.empty()
|
|
&& object->name().compare(0,
|
|
this->system_library_directory_.size(),
|
|
this->system_library_directory_) == 0);
|
|
}
|
|
|
|
// For each dynamic object, record whether we've seen all of its
|
|
// explicit dependencies.
|
|
|
|
void
|
|
Input_objects::check_dynamic_dependencies() const
|
|
{
|
|
for (Dynobj_list::const_iterator p = this->dynobj_list_.begin();
|
|
p != this->dynobj_list_.end();
|
|
++p)
|
|
{
|
|
const Dynobj::Needed& needed((*p)->needed());
|
|
bool found_all = true;
|
|
for (Dynobj::Needed::const_iterator pneeded = needed.begin();
|
|
pneeded != needed.end();
|
|
++pneeded)
|
|
{
|
|
if (this->sonames_.find(*pneeded) == this->sonames_.end())
|
|
{
|
|
found_all = false;
|
|
break;
|
|
}
|
|
}
|
|
(*p)->set_has_unknown_needed_entries(!found_all);
|
|
}
|
|
}
|
|
|
|
// Relocate_info methods.
|
|
|
|
// Return a string describing the location of a relocation. This is
|
|
// only used in error messages.
|
|
|
|
template<int size, bool big_endian>
|
|
std::string
|
|
Relocate_info<size, big_endian>::location(size_t, off_t offset) const
|
|
{
|
|
// See if we can get line-number information from debugging sections.
|
|
std::string filename;
|
|
std::string file_and_lineno; // Better than filename-only, if available.
|
|
|
|
Sized_dwarf_line_info<size, big_endian> line_info(this->object);
|
|
// This will be "" if we failed to parse the debug info for any reason.
|
|
file_and_lineno = line_info.addr2line(this->data_shndx, offset);
|
|
|
|
std::string ret(this->object->name());
|
|
ret += ':';
|
|
Symbol_location_info info;
|
|
if (this->object->get_symbol_location_info(this->data_shndx, offset, &info))
|
|
{
|
|
ret += " in function ";
|
|
ret += info.enclosing_symbol_name;
|
|
ret += ":";
|
|
filename = info.source_file;
|
|
}
|
|
|
|
if (!file_and_lineno.empty())
|
|
ret += file_and_lineno;
|
|
else
|
|
{
|
|
if (!filename.empty())
|
|
ret += filename;
|
|
ret += "(";
|
|
ret += this->object->section_name(this->data_shndx);
|
|
char buf[100];
|
|
// Offsets into sections have to be positive.
|
|
snprintf(buf, sizeof(buf), "+0x%lx", static_cast<long>(offset));
|
|
ret += buf;
|
|
ret += ")";
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
} // End namespace gold.
|
|
|
|
namespace
|
|
{
|
|
|
|
using namespace gold;
|
|
|
|
// Read an ELF file with the header and return the appropriate
|
|
// instance of Object.
|
|
|
|
template<int size, bool big_endian>
|
|
Object*
|
|
make_elf_sized_object(const std::string& name, Input_file* input_file,
|
|
off_t offset, const elfcpp::Ehdr<size, big_endian>& ehdr)
|
|
{
|
|
int et = ehdr.get_e_type();
|
|
if (et == elfcpp::ET_REL)
|
|
{
|
|
Sized_relobj<size, big_endian>* obj =
|
|
new Sized_relobj<size, big_endian>(name, input_file, offset, ehdr);
|
|
obj->setup(ehdr);
|
|
return obj;
|
|
}
|
|
else if (et == elfcpp::ET_DYN)
|
|
{
|
|
Sized_dynobj<size, big_endian>* obj =
|
|
new Sized_dynobj<size, big_endian>(name, input_file, offset, ehdr);
|
|
obj->setup(ehdr);
|
|
return obj;
|
|
}
|
|
else
|
|
{
|
|
gold_error(_("%s: unsupported ELF file type %d"),
|
|
name.c_str(), et);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
} // End anonymous namespace.
|
|
|
|
namespace gold
|
|
{
|
|
|
|
// Read an ELF file and return the appropriate instance of Object.
|
|
|
|
Object*
|
|
make_elf_object(const std::string& name, Input_file* input_file, off_t offset,
|
|
const unsigned char* p, section_offset_type bytes)
|
|
{
|
|
if (bytes < elfcpp::EI_NIDENT)
|
|
{
|
|
gold_error(_("%s: ELF file too short"), name.c_str());
|
|
return NULL;
|
|
}
|
|
|
|
int v = p[elfcpp::EI_VERSION];
|
|
if (v != elfcpp::EV_CURRENT)
|
|
{
|
|
if (v == elfcpp::EV_NONE)
|
|
gold_error(_("%s: invalid ELF version 0"), name.c_str());
|
|
else
|
|
gold_error(_("%s: unsupported ELF version %d"), name.c_str(), v);
|
|
return NULL;
|
|
}
|
|
|
|
int c = p[elfcpp::EI_CLASS];
|
|
if (c == elfcpp::ELFCLASSNONE)
|
|
{
|
|
gold_error(_("%s: invalid ELF class 0"), name.c_str());
|
|
return NULL;
|
|
}
|
|
else if (c != elfcpp::ELFCLASS32
|
|
&& c != elfcpp::ELFCLASS64)
|
|
{
|
|
gold_error(_("%s: unsupported ELF class %d"), name.c_str(), c);
|
|
return NULL;
|
|
}
|
|
|
|
int d = p[elfcpp::EI_DATA];
|
|
if (d == elfcpp::ELFDATANONE)
|
|
{
|
|
gold_error(_("%s: invalid ELF data encoding"), name.c_str());
|
|
return NULL;
|
|
}
|
|
else if (d != elfcpp::ELFDATA2LSB
|
|
&& d != elfcpp::ELFDATA2MSB)
|
|
{
|
|
gold_error(_("%s: unsupported ELF data encoding %d"), name.c_str(), d);
|
|
return NULL;
|
|
}
|
|
|
|
bool big_endian = d == elfcpp::ELFDATA2MSB;
|
|
|
|
if (c == elfcpp::ELFCLASS32)
|
|
{
|
|
if (bytes < elfcpp::Elf_sizes<32>::ehdr_size)
|
|
{
|
|
gold_error(_("%s: ELF file too short"), name.c_str());
|
|
return NULL;
|
|
}
|
|
if (big_endian)
|
|
{
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
elfcpp::Ehdr<32, true> ehdr(p);
|
|
return make_elf_sized_object<32, true>(name, input_file,
|
|
offset, ehdr);
|
|
#else
|
|
gold_error(_("%s: not configured to support "
|
|
"32-bit big-endian object"),
|
|
name.c_str());
|
|
return NULL;
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
elfcpp::Ehdr<32, false> ehdr(p);
|
|
return make_elf_sized_object<32, false>(name, input_file,
|
|
offset, ehdr);
|
|
#else
|
|
gold_error(_("%s: not configured to support "
|
|
"32-bit little-endian object"),
|
|
name.c_str());
|
|
return NULL;
|
|
#endif
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (bytes < elfcpp::Elf_sizes<64>::ehdr_size)
|
|
{
|
|
gold_error(_("%s: ELF file too short"), name.c_str());
|
|
return NULL;
|
|
}
|
|
if (big_endian)
|
|
{
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
elfcpp::Ehdr<64, true> ehdr(p);
|
|
return make_elf_sized_object<64, true>(name, input_file,
|
|
offset, ehdr);
|
|
#else
|
|
gold_error(_("%s: not configured to support "
|
|
"64-bit big-endian object"),
|
|
name.c_str());
|
|
return NULL;
|
|
#endif
|
|
}
|
|
else
|
|
{
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
elfcpp::Ehdr<64, false> ehdr(p);
|
|
return make_elf_sized_object<64, false>(name, input_file,
|
|
offset, ehdr);
|
|
#else
|
|
gold_error(_("%s: not configured to support "
|
|
"64-bit little-endian object"),
|
|
name.c_str());
|
|
return NULL;
|
|
#endif
|
|
}
|
|
}
|
|
}
|
|
|
|
// Instantiate the templates we need.
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
void
|
|
Object::read_section_data<32, false>(elfcpp::Elf_file<32, false, Object>*,
|
|
Read_symbols_data*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
void
|
|
Object::read_section_data<32, true>(elfcpp::Elf_file<32, true, Object>*,
|
|
Read_symbols_data*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
void
|
|
Object::read_section_data<64, false>(elfcpp::Elf_file<64, false, Object>*,
|
|
Read_symbols_data*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
void
|
|
Object::read_section_data<64, true>(elfcpp::Elf_file<64, true, Object>*,
|
|
Read_symbols_data*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
class Sized_relobj<32, false>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
class Sized_relobj<32, true>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
class Sized_relobj<64, false>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
class Sized_relobj<64, true>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
struct Relocate_info<32, false>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
struct Relocate_info<32, true>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
struct Relocate_info<64, false>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
struct Relocate_info<64, true>;
|
|
#endif
|
|
|
|
} // End namespace gold.
|