3128 lines
96 KiB
C++
3128 lines
96 KiB
C++
// object.cc -- support for an object file for linking in gold
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// Copyright 2006, 2007, 2008, 2009, 2010, 2011 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 "gc.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 "cref.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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#include "plugin.h"
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#include "compressed_output.h"
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#include "incremental.h"
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namespace gold
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{
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// Struct Read_symbols_data.
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// Destroy any remaining File_view objects.
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Read_symbols_data::~Read_symbols_data()
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{
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if (this->section_headers != NULL)
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delete this->section_headers;
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if (this->section_names != NULL)
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delete this->section_names;
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if (this->symbols != NULL)
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delete this->symbols;
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if (this->symbol_names != NULL)
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delete this->symbol_names;
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if (this->versym != NULL)
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delete this->versym;
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if (this->verdef != NULL)
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delete this->verdef;
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if (this->verneed != NULL)
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delete this->verneed;
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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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// 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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if (*plen == 0)
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{
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static const unsigned char empty[1] = { '\0' };
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return empty;
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}
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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_file
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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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if (len == 0)
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{
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const char* warning = name + warn_prefix_len;
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contents = reinterpret_cast<const unsigned char*>(warning);
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len = strlen(warning);
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}
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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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// If NAME is the name of the special section which indicates that
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// this object was compiled with -fsplit-stack, mark it accordingly.
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bool
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Object::handle_split_stack_section(const char* name)
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{
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if (strcmp(name, ".note.GNU-split-stack") == 0)
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{
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this->uses_split_stack_ = true;
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return true;
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}
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if (strcmp(name, ".note.GNU-no-split-stack") == 0)
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{
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this->has_no_split_stack_ = true;
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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 Relobj
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// To copy the symbols data read from the file to a local data structure.
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// This function is called from do_layout only while doing garbage
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// collection.
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void
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Relobj::copy_symbols_data(Symbols_data* gc_sd, Read_symbols_data* sd,
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unsigned int section_header_size)
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{
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gc_sd->section_headers_data =
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new unsigned char[(section_header_size)];
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memcpy(gc_sd->section_headers_data, sd->section_headers->data(),
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section_header_size);
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gc_sd->section_names_data =
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new unsigned char[sd->section_names_size];
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memcpy(gc_sd->section_names_data, sd->section_names->data(),
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sd->section_names_size);
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gc_sd->section_names_size = sd->section_names_size;
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if (sd->symbols != NULL)
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{
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gc_sd->symbols_data =
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new unsigned char[sd->symbols_size];
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memcpy(gc_sd->symbols_data, sd->symbols->data(),
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sd->symbols_size);
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}
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else
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{
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gc_sd->symbols_data = NULL;
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}
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gc_sd->symbols_size = sd->symbols_size;
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gc_sd->external_symbols_offset = sd->external_symbols_offset;
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if (sd->symbol_names != NULL)
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{
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gc_sd->symbol_names_data =
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new unsigned char[sd->symbol_names_size];
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memcpy(gc_sd->symbol_names_data, sd->symbol_names->data(),
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sd->symbol_names_size);
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}
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else
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{
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gc_sd->symbol_names_data = NULL;
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}
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gc_sd->symbol_names_size = sd->symbol_names_size;
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}
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// This function determines if a particular section name must be included
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// in the link. This is used during garbage collection to determine the
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// roots of the worklist.
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bool
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Relobj::is_section_name_included(const char* name)
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{
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if (is_prefix_of(".ctors", name)
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|| is_prefix_of(".dtors", name)
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|| is_prefix_of(".note", name)
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|| is_prefix_of(".init", name)
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|| is_prefix_of(".fini", name)
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|| is_prefix_of(".gcc_except_table", name)
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|| is_prefix_of(".jcr", name)
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|| is_prefix_of(".preinit_array", name)
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|| (is_prefix_of(".text", name)
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&& strstr(name, "personality"))
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|| (is_prefix_of(".data", name)
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&& strstr(name, "personality"))
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|| (is_prefix_of(".gnu.linkonce.d", name)
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&& strstr(name, "personality")))
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{
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return true;
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}
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return false;
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}
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// Finalize the incremental relocation information. Allocates a block
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// of relocation entries for each symbol, and sets the reloc_bases_
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// array to point to the first entry in each block. If CLEAR_COUNTS
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// is TRUE, also clear the per-symbol relocation counters.
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void
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Relobj::finalize_incremental_relocs(Layout* layout, bool clear_counts)
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{
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unsigned int nsyms = this->get_global_symbols()->size();
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this->reloc_bases_ = new unsigned int[nsyms];
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gold_assert(this->reloc_bases_ != NULL);
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gold_assert(layout->incremental_inputs() != NULL);
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unsigned int rindex = layout->incremental_inputs()->get_reloc_count();
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for (unsigned int i = 0; i < nsyms; ++i)
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{
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this->reloc_bases_[i] = rindex;
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rindex += this->reloc_counts_[i];
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if (clear_counts)
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this->reloc_counts_[i] = 0;
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}
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layout->incremental_inputs()->set_reloc_count(rindex);
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}
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// Class Sized_relobj.
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// Iterate over local symbols, calling a visitor class V for each GOT offset
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// associated with a local symbol.
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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_for_all_local_got_entries(
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Got_offset_list::Visitor* v) const
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{
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unsigned int nsyms = this->local_symbol_count();
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for (unsigned int i = 0; i < nsyms; i++)
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{
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Local_got_offsets::const_iterator p = this->local_got_offsets_.find(i);
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if (p != this->local_got_offsets_.end())
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{
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const Got_offset_list* got_offsets = p->second;
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got_offsets->for_all_got_offsets(v);
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}
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}
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}
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// Class Sized_relobj_file.
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template<int size, bool big_endian>
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Sized_relobj_file<size, big_endian>::Sized_relobj_file(
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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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: Sized_relobj<size, big_endian>(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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defined_count_(0),
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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_plt_offsets_(),
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kept_comdat_sections_(),
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has_eh_frame_(false),
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discarded_eh_frame_shndx_(-1U),
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deferred_layout_(),
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deferred_layout_relocs_(),
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compressed_sections_()
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{
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this->e_type_ = ehdr.get_e_type();
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}
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template<int size, bool big_endian>
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Sized_relobj_file<size, big_endian>::~Sized_relobj_file()
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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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// section information.
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template<int size, bool big_endian>
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void
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Sized_relobj_file<size, big_endian>::do_setup()
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{
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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_file<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_file<size, big_endian>::do_initialize_xindex()
|
|
{
|
|
gold_assert(this->symtab_shndx_ != -1U);
|
|
Xindex* xindex = new Xindex(this->elf_file_.large_shndx_offset());
|
|
xindex->initialize_symtab_xindex<size, big_endian>(this, this->symtab_shndx_);
|
|
return xindex;
|
|
}
|
|
|
|
// Return whether SHDR has the right type and flags to be a GNU
|
|
// .eh_frame section.
|
|
|
|
template<int size, bool big_endian>
|
|
bool
|
|
Sized_relobj_file<size, big_endian>::check_eh_frame_flags(
|
|
const elfcpp::Shdr<size, big_endian>* shdr) const
|
|
{
|
|
elfcpp::Elf_Word sh_type = shdr->get_sh_type();
|
|
return ((sh_type == elfcpp::SHT_PROGBITS
|
|
|| sh_type == elfcpp::SHT_X86_64_UNWIND)
|
|
&& (shdr->get_sh_flags() & elfcpp::SHF_ALLOC) != 0);
|
|
}
|
|
|
|
// Return whether there is a GNU .eh_frame section, given the section
|
|
// headers and the section names.
|
|
|
|
template<int size, bool big_endian>
|
|
bool
|
|
Sized_relobj_file<size, big_endian>::find_eh_frame(
|
|
const unsigned char* pshdrs,
|
|
const char* names,
|
|
section_size_type names_size) const
|
|
{
|
|
const unsigned int shnum = this->shnum();
|
|
const unsigned char* p = pshdrs + This::shdr_size;
|
|
for (unsigned int i = 1; i < shnum; ++i, p += This::shdr_size)
|
|
{
|
|
typename This::Shdr shdr(p);
|
|
if (this->check_eh_frame_flags(&shdr))
|
|
{
|
|
if (shdr.get_sh_name() >= names_size)
|
|
{
|
|
this->error(_("bad section name offset for section %u: %lu"),
|
|
i, static_cast<unsigned long>(shdr.get_sh_name()));
|
|
continue;
|
|
}
|
|
|
|
const char* name = names + shdr.get_sh_name();
|
|
if (strcmp(name, ".eh_frame") == 0)
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
#ifdef ENABLE_THREADS
|
|
|
|
// Return TRUE if this is a section whose contents will be needed in the
|
|
// Add_symbols task.
|
|
|
|
static bool
|
|
need_decompressed_section(const char* name)
|
|
{
|
|
// We will need .zdebug_str if this is not an incremental link
|
|
// (i.e., we are processing string merge sections).
|
|
if (!parameters->incremental() && strcmp(name, ".zdebug_str") == 0)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
#endif
|
|
|
|
// Build a table for any compressed debug sections, mapping each section index
|
|
// to the uncompressed size and (if needed) the decompressed contents.
|
|
|
|
template<int size, bool big_endian>
|
|
Compressed_section_map*
|
|
build_compressed_section_map(
|
|
const unsigned char* pshdrs,
|
|
unsigned int shnum,
|
|
const char* names,
|
|
section_size_type names_size,
|
|
Sized_relobj_file<size, big_endian>* obj)
|
|
{
|
|
Compressed_section_map* uncompressed_map = new Compressed_section_map();
|
|
const unsigned int shdr_size = elfcpp::Elf_sizes<size>::shdr_size;
|
|
const unsigned char* p = pshdrs + shdr_size;
|
|
|
|
for (unsigned int i = 1; i < shnum; ++i, p += shdr_size)
|
|
{
|
|
typename elfcpp::Shdr<size, big_endian> shdr(p);
|
|
if (shdr.get_sh_type() == elfcpp::SHT_PROGBITS
|
|
&& (shdr.get_sh_flags() & elfcpp::SHF_ALLOC) == 0)
|
|
{
|
|
if (shdr.get_sh_name() >= names_size)
|
|
{
|
|
obj->error(_("bad section name offset for section %u: %lu"),
|
|
i, static_cast<unsigned long>(shdr.get_sh_name()));
|
|
continue;
|
|
}
|
|
|
|
const char* name = names + shdr.get_sh_name();
|
|
if (is_compressed_debug_section(name))
|
|
{
|
|
section_size_type len;
|
|
const unsigned char* contents =
|
|
obj->section_contents(i, &len, false);
|
|
uint64_t uncompressed_size = get_uncompressed_size(contents, len);
|
|
if (uncompressed_size != -1ULL)
|
|
{
|
|
Compressed_section_info info;
|
|
info.size = convert_to_section_size_type(uncompressed_size);
|
|
info.contents = NULL;
|
|
|
|
#ifdef ENABLE_THREADS
|
|
// If we're multi-threaded, it will help to decompress
|
|
// any sections that will be needed during the Add_symbols
|
|
// task, so that several decompressions can run in
|
|
// parallel.
|
|
if (parameters->options().threads())
|
|
{
|
|
unsigned char* uncompressed_data = NULL;
|
|
if (need_decompressed_section(name))
|
|
{
|
|
uncompressed_data = new unsigned char[uncompressed_size];
|
|
if (decompress_input_section(contents, len,
|
|
uncompressed_data,
|
|
uncompressed_size))
|
|
info.contents = uncompressed_data;
|
|
else
|
|
delete[] uncompressed_data;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
(*uncompressed_map)[i] = info;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return uncompressed_map;
|
|
}
|
|
|
|
// Read the sections and symbols from an object file.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_read_symbols(Read_symbols_data* sd)
|
|
{
|
|
this->read_section_data(&this->elf_file_, sd);
|
|
|
|
const unsigned char* const pshdrs = sd->section_headers->data();
|
|
|
|
this->find_symtab(pshdrs);
|
|
|
|
const unsigned char* namesu = sd->section_names->data();
|
|
const char* names = reinterpret_cast<const char*>(namesu);
|
|
if (memmem(names, sd->section_names_size, ".eh_frame", 10) != NULL)
|
|
{
|
|
if (this->find_eh_frame(pshdrs, names, sd->section_names_size))
|
|
this->has_eh_frame_ = true;
|
|
}
|
|
if (memmem(names, sd->section_names_size, ".zdebug_", 8) != NULL)
|
|
this->compressed_sections_ =
|
|
build_compressed_section_map(pshdrs, this->shnum(), names,
|
|
sd->section_names_size, this);
|
|
|
|
sd->symbols = NULL;
|
|
sd->symbols_size = 0;
|
|
sd->external_symbols_offset = 0;
|
|
sd->symbol_names = NULL;
|
|
sd->symbol_names_size = 0;
|
|
|
|
if (this->symtab_shndx_ == 0)
|
|
{
|
|
// No symbol table. Weird but legal.
|
|
return;
|
|
}
|
|
|
|
// Get the symbol table section header.
|
|
typename This::Shdr symtabshdr(pshdrs
|
|
+ this->symtab_shndx_ * This::shdr_size);
|
|
gold_assert(symtabshdr.get_sh_type() == elfcpp::SHT_SYMTAB);
|
|
|
|
// If this object has a .eh_frame section, we need all the symbols.
|
|
// Otherwise we only need the external symbols. While it would be
|
|
// simpler to just always read all the symbols, I've seen object
|
|
// files with well over 2000 local symbols, which for a 64-bit
|
|
// object file format is over 5 pages that we don't need to read
|
|
// now.
|
|
|
|
const int sym_size = This::sym_size;
|
|
const unsigned int loccount = symtabshdr.get_sh_info();
|
|
this->local_symbol_count_ = loccount;
|
|
this->local_values_.resize(loccount);
|
|
section_offset_type locsize = loccount * sym_size;
|
|
off_t dataoff = symtabshdr.get_sh_offset();
|
|
section_size_type datasize =
|
|
convert_to_section_size_type(symtabshdr.get_sh_size());
|
|
off_t extoff = dataoff + locsize;
|
|
section_size_type extsize = datasize - locsize;
|
|
|
|
off_t readoff = this->has_eh_frame_ ? dataoff : extoff;
|
|
section_size_type readsize = this->has_eh_frame_ ? datasize : extsize;
|
|
|
|
if (readsize == 0)
|
|
{
|
|
// No external symbols. Also weird but also legal.
|
|
return;
|
|
}
|
|
|
|
File_view* fvsymtab = this->get_lasting_view(readoff, readsize, true, false);
|
|
|
|
// Read the section header for the symbol names.
|
|
unsigned int strtab_shndx = this->adjust_shndx(symtabshdr.get_sh_link());
|
|
if (strtab_shndx >= this->shnum())
|
|
{
|
|
this->error(_("invalid symbol table name index: %u"), strtab_shndx);
|
|
return;
|
|
}
|
|
typename This::Shdr strtabshdr(pshdrs + strtab_shndx * This::shdr_size);
|
|
if (strtabshdr.get_sh_type() != elfcpp::SHT_STRTAB)
|
|
{
|
|
this->error(_("symbol table name section has wrong type: %u"),
|
|
static_cast<unsigned int>(strtabshdr.get_sh_type()));
|
|
return;
|
|
}
|
|
|
|
// Read the symbol names.
|
|
File_view* fvstrtab = this->get_lasting_view(strtabshdr.get_sh_offset(),
|
|
strtabshdr.get_sh_size(),
|
|
false, true);
|
|
|
|
sd->symbols = fvsymtab;
|
|
sd->symbols_size = readsize;
|
|
sd->external_symbols_offset = this->has_eh_frame_ ? locsize : 0;
|
|
sd->symbol_names = fvstrtab;
|
|
sd->symbol_names_size =
|
|
convert_to_section_size_type(strtabshdr.get_sh_size());
|
|
}
|
|
|
|
// Return the section index of symbol SYM. Set *VALUE to its value in
|
|
// the object file. Set *IS_ORDINARY if this is an ordinary section
|
|
// index, not a special code between SHN_LORESERVE and SHN_HIRESERVE.
|
|
// Note that for a symbol which is not defined in this object file,
|
|
// this will set *VALUE to 0 and return SHN_UNDEF; it will not return
|
|
// the final value of the symbol in the link.
|
|
|
|
template<int size, bool big_endian>
|
|
unsigned int
|
|
Sized_relobj_file<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_file<size, big_endian>::include_section_group(
|
|
Symbol_table* symtab,
|
|
Layout* layout,
|
|
unsigned int index,
|
|
const char* name,
|
|
const unsigned char* shdrs,
|
|
const char* section_names,
|
|
section_size_type section_names_size,
|
|
std::vector<bool>* omit)
|
|
{
|
|
// Read the section contents.
|
|
typename This::Shdr shdr(shdrs + index * This::shdr_size);
|
|
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. ELF
|
|
// uses a symbol name because some group signatures are long, and
|
|
// the name is generally already in the symbol table, so it makes
|
|
// sense to put the long string just once in .strtab rather than in
|
|
// both .strtab and .shstrtab.
|
|
|
|
// 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;
|
|
}
|
|
|
|
std::string 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.
|
|
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;
|
|
}
|
|
typename This::Shdr member_shdr(shdrs + sym_shndx * This::shdr_size);
|
|
if (member_shdr.get_sh_name() < section_names_size)
|
|
signature = section_names + member_shdr.get_sh_name();
|
|
}
|
|
|
|
// Record this section group in the layout, and see whether we've already
|
|
// seen one with the same signature.
|
|
bool include_group;
|
|
bool is_comdat;
|
|
Kept_section* kept_section = NULL;
|
|
|
|
if ((flags & elfcpp::GRP_COMDAT) == 0)
|
|
{
|
|
include_group = true;
|
|
is_comdat = false;
|
|
}
|
|
else
|
|
{
|
|
include_group = layout->find_or_add_kept_section(signature,
|
|
this, index, true,
|
|
true, &kept_section);
|
|
is_comdat = true;
|
|
}
|
|
|
|
if (is_comdat && include_group)
|
|
{
|
|
Incremental_inputs* incremental_inputs = layout->incremental_inputs();
|
|
if (incremental_inputs != NULL)
|
|
incremental_inputs->report_comdat_group(this, signature.c_str());
|
|
}
|
|
|
|
size_t count = shdr.get_sh_size() / sizeof(elfcpp::Elf_Word);
|
|
|
|
std::vector<unsigned int> shndxes;
|
|
bool relocate_group = include_group && parameters->options().relocatable();
|
|
if (relocate_group)
|
|
shndxes.reserve(count - 1);
|
|
|
|
for (size_t i = 1; i < count; ++i)
|
|
{
|
|
elfcpp::Elf_Word shndx =
|
|
this->adjust_shndx(elfcpp::Swap<32, big_endian>::readval(pword + i));
|
|
|
|
if (relocate_group)
|
|
shndxes.push_back(shndx);
|
|
|
|
if (shndx >= this->shnum())
|
|
{
|
|
this->error(_("section %u in section group %u out of range"),
|
|
shndx, 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 (shndx < index)
|
|
this->error(_("invalid section group %u refers to earlier section %u"),
|
|
index, shndx);
|
|
|
|
// Get the name of the member section.
|
|
typename This::Shdr member_shdr(shdrs + shndx * This::shdr_size);
|
|
if (member_shdr.get_sh_name() >= section_names_size)
|
|
{
|
|
// This is an error, but it will be diagnosed eventually
|
|
// in do_layout, so we don't need to do anything here but
|
|
// ignore it.
|
|
continue;
|
|
}
|
|
std::string mname(section_names + member_shdr.get_sh_name());
|
|
|
|
if (include_group)
|
|
{
|
|
if (is_comdat)
|
|
kept_section->add_comdat_section(mname, shndx,
|
|
member_shdr.get_sh_size());
|
|
}
|
|
else
|
|
{
|
|
(*omit)[shndx] = true;
|
|
|
|
if (is_comdat)
|
|
{
|
|
Relobj* kept_object = kept_section->object();
|
|
if (kept_section->is_comdat())
|
|
{
|
|
// Find the corresponding kept section, and store
|
|
// that info in the discarded section table.
|
|
unsigned int kept_shndx;
|
|
uint64_t kept_size;
|
|
if (kept_section->find_comdat_section(mname, &kept_shndx,
|
|
&kept_size))
|
|
{
|
|
// We don't keep a mapping for this section if
|
|
// it has a different size. The mapping is only
|
|
// used for relocation processing, and we don't
|
|
// want to treat the sections as similar if the
|
|
// sizes are different. Checking the section
|
|
// size is the approach used by the GNU linker.
|
|
if (kept_size == member_shdr.get_sh_size())
|
|
this->set_kept_comdat_section(shndx, kept_object,
|
|
kept_shndx);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
// The existing section is a linkonce section. Add
|
|
// a mapping if there is exactly one section in the
|
|
// group (which is true when COUNT == 2) and if it
|
|
// is the same size.
|
|
if (count == 2
|
|
&& (kept_section->linkonce_size()
|
|
== member_shdr.get_sh_size()))
|
|
this->set_kept_comdat_section(shndx, kept_object,
|
|
kept_section->shndx());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (relocate_group)
|
|
layout->layout_group(symtab, this, index, name, signature.c_str(),
|
|
shdr, flags, &shndxes);
|
|
|
|
return include_group;
|
|
}
|
|
|
|
// 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_file<size, big_endian>::include_linkonce_section(
|
|
Layout* layout,
|
|
unsigned int index,
|
|
const char* name,
|
|
const elfcpp::Shdr<size, big_endian>& shdr)
|
|
{
|
|
typename elfcpp::Elf_types<size>::Elf_WXword sh_size = shdr.get_sh_size();
|
|
// 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;
|
|
std::string sig1(symname);
|
|
std::string sig2(name);
|
|
Kept_section* kept1;
|
|
Kept_section* kept2;
|
|
bool include1 = layout->find_or_add_kept_section(sig1, this, index, false,
|
|
false, &kept1);
|
|
bool include2 = layout->find_or_add_kept_section(sig2, this, index, false,
|
|
true, &kept2);
|
|
|
|
if (!include2)
|
|
{
|
|
// We are not including this section because we already saw the
|
|
// name of the section as a signature. This normally implies
|
|
// that the kept section is another linkonce section. If it is
|
|
// the same size, record it as the section which corresponds to
|
|
// this one.
|
|
if (kept2->object() != NULL
|
|
&& !kept2->is_comdat()
|
|
&& kept2->linkonce_size() == sh_size)
|
|
this->set_kept_comdat_section(index, kept2->object(), kept2->shndx());
|
|
}
|
|
else if (!include1)
|
|
{
|
|
// The section is being discarded on the basis of its symbol
|
|
// name. This means that the corresponding kept section was
|
|
// part of a comdat group, and it will be difficult to identify
|
|
// the specific section within that group that corresponds to
|
|
// this linkonce section. We'll handle the simple case where
|
|
// the group has only one member section. Otherwise, it's not
|
|
// worth the effort.
|
|
unsigned int kept_shndx;
|
|
uint64_t kept_size;
|
|
if (kept1->object() != NULL
|
|
&& kept1->is_comdat()
|
|
&& kept1->find_single_comdat_section(&kept_shndx, &kept_size)
|
|
&& kept_size == sh_size)
|
|
this->set_kept_comdat_section(index, kept1->object(), kept_shndx);
|
|
}
|
|
else
|
|
{
|
|
kept1->set_linkonce_size(sh_size);
|
|
kept2->set_linkonce_size(sh_size);
|
|
}
|
|
|
|
return include1 && include2;
|
|
}
|
|
|
|
// Layout an input section.
|
|
|
|
template<int size, bool big_endian>
|
|
inline void
|
|
Sized_relobj_file<size, big_endian>::layout_section(
|
|
Layout* layout,
|
|
unsigned int shndx,
|
|
const char* name,
|
|
const typename This::Shdr& shdr,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type)
|
|
{
|
|
off_t offset;
|
|
Output_section* os = layout->layout(this, shndx, name, shdr,
|
|
reloc_shndx, reloc_type, &offset);
|
|
|
|
this->output_sections()[shndx] = os;
|
|
if (offset == -1)
|
|
this->section_offsets()[shndx] = invalid_address;
|
|
else
|
|
this->section_offsets()[shndx] = convert_types<Address, off_t>(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 != 0)
|
|
this->set_relocs_must_follow_section_writes();
|
|
}
|
|
|
|
// Layout an input .eh_frame section.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::layout_eh_frame_section(
|
|
Layout* layout,
|
|
const unsigned char* symbols_data,
|
|
section_size_type symbols_size,
|
|
const unsigned char* symbol_names_data,
|
|
section_size_type symbol_names_size,
|
|
unsigned int shndx,
|
|
const typename This::Shdr& shdr,
|
|
unsigned int reloc_shndx,
|
|
unsigned int reloc_type)
|
|
{
|
|
gold_assert(this->has_eh_frame_);
|
|
|
|
off_t offset;
|
|
Output_section* os = layout->layout_eh_frame(this,
|
|
symbols_data,
|
|
symbols_size,
|
|
symbol_names_data,
|
|
symbol_names_size,
|
|
shndx,
|
|
shdr,
|
|
reloc_shndx,
|
|
reloc_type,
|
|
&offset);
|
|
this->output_sections()[shndx] = os;
|
|
if (os == NULL || offset == -1)
|
|
{
|
|
// An object can contain at most one section holding exception
|
|
// frame information.
|
|
gold_assert(this->discarded_eh_frame_shndx_ == -1U);
|
|
this->discarded_eh_frame_shndx_ = shndx;
|
|
this->section_offsets()[shndx] = invalid_address;
|
|
}
|
|
else
|
|
this->section_offsets()[shndx] = convert_types<Address, off_t>(offset);
|
|
|
|
// If this section requires special handling, and if there are
|
|
// relocs that aply to it, then we must do the special handling
|
|
// before we apply the relocs.
|
|
if (os != NULL && offset == -1 && reloc_shndx != 0)
|
|
this->set_relocs_must_follow_section_writes();
|
|
}
|
|
|
|
// 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.
|
|
// During garbage collection (--gc-sections) and identical code folding
|
|
// (--icf), this function is called twice. When it is called the first
|
|
// time, it is for setting up some sections as roots to a work-list for
|
|
// --gc-sections and to do comdat processing. Actual layout happens the
|
|
// second time around after all the relevant sections have been determined.
|
|
// The first time, is_worklist_ready or is_icf_ready is false. It is then
|
|
// set to true after the garbage collection worklist or identical code
|
|
// folding is processed and the relevant sections to be kept are
|
|
// determined. Then, this function is called again to layout the sections.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_layout(Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_symbols_data* sd)
|
|
{
|
|
const unsigned int shnum = this->shnum();
|
|
bool is_gc_pass_one = ((parameters->options().gc_sections()
|
|
&& !symtab->gc()->is_worklist_ready())
|
|
|| (parameters->options().icf_enabled()
|
|
&& !symtab->icf()->is_icf_ready()));
|
|
|
|
bool is_gc_pass_two = ((parameters->options().gc_sections()
|
|
&& symtab->gc()->is_worklist_ready())
|
|
|| (parameters->options().icf_enabled()
|
|
&& symtab->icf()->is_icf_ready()));
|
|
|
|
bool is_gc_or_icf = (parameters->options().gc_sections()
|
|
|| parameters->options().icf_enabled());
|
|
|
|
// Both is_gc_pass_one and is_gc_pass_two should not be true.
|
|
gold_assert(!(is_gc_pass_one && is_gc_pass_two));
|
|
|
|
if (shnum == 0)
|
|
return;
|
|
Symbols_data* gc_sd = NULL;
|
|
if (is_gc_pass_one)
|
|
{
|
|
// During garbage collection save the symbols data to use it when
|
|
// re-entering this function.
|
|
gc_sd = new Symbols_data;
|
|
this->copy_symbols_data(gc_sd, sd, This::shdr_size * shnum);
|
|
this->set_symbols_data(gc_sd);
|
|
}
|
|
else if (is_gc_pass_two)
|
|
{
|
|
gc_sd = this->get_symbols_data();
|
|
}
|
|
|
|
const unsigned char* section_headers_data = NULL;
|
|
section_size_type section_names_size;
|
|
const unsigned char* symbols_data = NULL;
|
|
section_size_type symbols_size;
|
|
const unsigned char* symbol_names_data = NULL;
|
|
section_size_type symbol_names_size;
|
|
|
|
if (is_gc_or_icf)
|
|
{
|
|
section_headers_data = gc_sd->section_headers_data;
|
|
section_names_size = gc_sd->section_names_size;
|
|
symbols_data = gc_sd->symbols_data;
|
|
symbols_size = gc_sd->symbols_size;
|
|
symbol_names_data = gc_sd->symbol_names_data;
|
|
symbol_names_size = gc_sd->symbol_names_size;
|
|
}
|
|
else
|
|
{
|
|
section_headers_data = sd->section_headers->data();
|
|
section_names_size = sd->section_names_size;
|
|
if (sd->symbols != NULL)
|
|
symbols_data = sd->symbols->data();
|
|
symbols_size = sd->symbols_size;
|
|
if (sd->symbol_names != NULL)
|
|
symbol_names_data = sd->symbol_names->data();
|
|
symbol_names_size = sd->symbol_names_size;
|
|
}
|
|
|
|
// Get the section headers.
|
|
const unsigned char* shdrs = section_headers_data;
|
|
const unsigned char* pshdrs;
|
|
|
|
// Get the section names.
|
|
const unsigned char* pnamesu = (is_gc_or_icf)
|
|
? gc_sd->section_names_data
|
|
: sd->section_names->data();
|
|
|
|
const char* pnames = reinterpret_cast<const char*>(pnamesu);
|
|
|
|
// If any input files have been claimed by plugins, we need to defer
|
|
// actual layout until the replacement files have arrived.
|
|
const bool should_defer_layout =
|
|
(parameters->options().has_plugins()
|
|
&& parameters->options().plugins()->should_defer_layout());
|
|
unsigned int num_sections_to_defer = 0;
|
|
|
|
// 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 = shdrs + This::shdr_size;
|
|
for (unsigned int i = 1; i < shnum; ++i, pshdrs += This::shdr_size)
|
|
{
|
|
typename This::Shdr shdr(pshdrs);
|
|
|
|
// Count the number of sections whose layout will be deferred.
|
|
if (should_defer_layout && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC))
|
|
++num_sections_to_defer;
|
|
|
|
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;
|
|
}
|
|
}
|
|
}
|
|
|
|
Output_sections& out_sections(this->output_sections());
|
|
std::vector<Address>& out_section_offsets(this->section_offsets());
|
|
|
|
if (!is_gc_pass_two)
|
|
{
|
|
out_sections.resize(shnum);
|
|
out_section_offsets.resize(shnum);
|
|
}
|
|
|
|
// If we are only linking for symbols, then there is nothing else to
|
|
// do here.
|
|
if (this->input_file()->just_symbols())
|
|
{
|
|
if (!is_gc_pass_two)
|
|
{
|
|
delete sd->section_headers;
|
|
sd->section_headers = NULL;
|
|
delete sd->section_names;
|
|
sd->section_names = NULL;
|
|
}
|
|
return;
|
|
}
|
|
|
|
if (num_sections_to_defer > 0)
|
|
{
|
|
parameters->options().plugins()->add_deferred_layout_object(this);
|
|
this->deferred_layout_.reserve(num_sections_to_defer);
|
|
}
|
|
|
|
// 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 = shdrs + 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() >= 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 (!is_gc_pass_two)
|
|
{
|
|
if (this->handle_gnu_warning_section(name, i, symtab))
|
|
{
|
|
if (!relocatable && !parameters->options().shared())
|
|
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;
|
|
}
|
|
|
|
// The .note.GNU-split-stack section is also special. It
|
|
// indicates that the object was compiled with
|
|
// -fsplit-stack.
|
|
if (this->handle_split_stack_section(name))
|
|
{
|
|
if (!relocatable && !parameters->options().shared())
|
|
omit[i] = true;
|
|
}
|
|
|
|
// Skip attributes section.
|
|
if (parameters->target().is_attributes_section(name))
|
|
{
|
|
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,
|
|
shdrs, pnames,
|
|
section_names_size,
|
|
&omit))
|
|
discard = true;
|
|
}
|
|
else if ((shdr.get_sh_flags() & elfcpp::SHF_GROUP) == 0
|
|
&& Layout::is_linkonce(name))
|
|
{
|
|
if (!this->include_linkonce_section(layout, i, name, shdr))
|
|
discard = true;
|
|
}
|
|
}
|
|
|
|
// Add the section to the incremental inputs layout.
|
|
Incremental_inputs* incremental_inputs = layout->incremental_inputs();
|
|
if (incremental_inputs != NULL
|
|
&& !discard
|
|
&& can_incremental_update(shdr.get_sh_type()))
|
|
{
|
|
off_t sh_size = shdr.get_sh_size();
|
|
section_size_type uncompressed_size;
|
|
if (this->section_is_compressed(i, &uncompressed_size))
|
|
sh_size = uncompressed_size;
|
|
incremental_inputs->report_input_section(this, i, name, sh_size);
|
|
}
|
|
|
|
if (discard)
|
|
{
|
|
// Do not include this section in the link.
|
|
out_sections[i] = NULL;
|
|
out_section_offsets[i] = invalid_address;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if (is_gc_pass_one && parameters->options().gc_sections())
|
|
{
|
|
if (this->is_section_name_included(name)
|
|
|| shdr.get_sh_type() == elfcpp::SHT_INIT_ARRAY
|
|
|| shdr.get_sh_type() == elfcpp::SHT_FINI_ARRAY)
|
|
{
|
|
symtab->gc()->worklist().push(Section_id(this, i));
|
|
}
|
|
// If the section name XXX can be represented as a C identifier
|
|
// it cannot be discarded if there are references to
|
|
// __start_XXX and __stop_XXX symbols. These need to be
|
|
// specially handled.
|
|
if (is_cident(name))
|
|
{
|
|
symtab->gc()->add_cident_section(name, Section_id(this, i));
|
|
}
|
|
}
|
|
|
|
// 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. Garbage collection is
|
|
// not triggered when relocatable code is desired.
|
|
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))
|
|
{
|
|
if (is_gc_pass_one)
|
|
{
|
|
out_sections[i] = reinterpret_cast<Output_section*>(1);
|
|
out_section_offsets[i] = invalid_address;
|
|
}
|
|
else if (should_defer_layout)
|
|
this->deferred_layout_.push_back(Deferred_layout(i, name,
|
|
pshdrs,
|
|
reloc_shndx[i],
|
|
reloc_type[i]));
|
|
else
|
|
eh_frame_sections.push_back(i);
|
|
continue;
|
|
}
|
|
|
|
if (is_gc_pass_two && parameters->options().gc_sections())
|
|
{
|
|
// This is executed during the second pass of garbage
|
|
// collection. do_layout has been called before and some
|
|
// sections have been already discarded. Simply ignore
|
|
// such sections this time around.
|
|
if (out_sections[i] == NULL)
|
|
{
|
|
gold_assert(out_section_offsets[i] == invalid_address);
|
|
continue;
|
|
}
|
|
if (((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0)
|
|
&& symtab->gc()->is_section_garbage(this, i))
|
|
{
|
|
if (parameters->options().print_gc_sections())
|
|
gold_info(_("%s: removing unused section from '%s'"
|
|
" in file '%s'"),
|
|
program_name, this->section_name(i).c_str(),
|
|
this->name().c_str());
|
|
out_sections[i] = NULL;
|
|
out_section_offsets[i] = invalid_address;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
if (is_gc_pass_two && parameters->options().icf_enabled())
|
|
{
|
|
if (out_sections[i] == NULL)
|
|
{
|
|
gold_assert(out_section_offsets[i] == invalid_address);
|
|
continue;
|
|
}
|
|
if (((shdr.get_sh_flags() & elfcpp::SHF_ALLOC) != 0)
|
|
&& symtab->icf()->is_section_folded(this, i))
|
|
{
|
|
if (parameters->options().print_icf_sections())
|
|
{
|
|
Section_id folded =
|
|
symtab->icf()->get_folded_section(this, i);
|
|
Relobj* folded_obj =
|
|
reinterpret_cast<Relobj*>(folded.first);
|
|
gold_info(_("%s: ICF folding section '%s' in file '%s'"
|
|
"into '%s' in file '%s'"),
|
|
program_name, this->section_name(i).c_str(),
|
|
this->name().c_str(),
|
|
folded_obj->section_name(folded.second).c_str(),
|
|
folded_obj->name().c_str());
|
|
}
|
|
out_sections[i] = NULL;
|
|
out_section_offsets[i] = invalid_address;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
// Defer layout here if input files are claimed by plugins. When gc
|
|
// is turned on this function is called twice. For the second call
|
|
// should_defer_layout should be false.
|
|
if (should_defer_layout && (shdr.get_sh_flags() & elfcpp::SHF_ALLOC))
|
|
{
|
|
gold_assert(!is_gc_pass_two);
|
|
this->deferred_layout_.push_back(Deferred_layout(i, name,
|
|
pshdrs,
|
|
reloc_shndx[i],
|
|
reloc_type[i]));
|
|
// Put dummy values here; real values will be supplied by
|
|
// do_layout_deferred_sections.
|
|
out_sections[i] = reinterpret_cast<Output_section*>(2);
|
|
out_section_offsets[i] = invalid_address;
|
|
continue;
|
|
}
|
|
|
|
// During gc_pass_two if a section that was previously deferred is
|
|
// found, do not layout the section as layout_deferred_sections will
|
|
// do it later from gold.cc.
|
|
if (is_gc_pass_two
|
|
&& (out_sections[i] == reinterpret_cast<Output_section*>(2)))
|
|
continue;
|
|
|
|
if (is_gc_pass_one)
|
|
{
|
|
// This is during garbage collection. The out_sections are
|
|
// assigned in the second call to this function.
|
|
out_sections[i] = reinterpret_cast<Output_section*>(1);
|
|
out_section_offsets[i] = invalid_address;
|
|
}
|
|
else
|
|
{
|
|
// When garbage collection is switched on the actual layout
|
|
// only happens in the second call.
|
|
this->layout_section(layout, i, name, shdr, reloc_shndx[i],
|
|
reloc_type[i]);
|
|
}
|
|
}
|
|
|
|
if (!is_gc_pass_two)
|
|
layout->layout_gnu_stack(seen_gnu_stack, gnu_stack_flags, this);
|
|
|
|
// When doing a relocatable link handle the reloc sections at the
|
|
// end. Garbage collection and Identical Code Folding is not
|
|
// turned on for relocatable code.
|
|
if (emit_relocs)
|
|
this->size_relocatable_relocs();
|
|
|
|
gold_assert(!(is_gc_or_icf) || reloc_sections.empty());
|
|
|
|
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 = 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 = out_sections[data_shndx];
|
|
if (data_section == reinterpret_cast<Output_section*>(2))
|
|
{
|
|
// The layout for the data section was deferred, so we need
|
|
// to defer the relocation section, too.
|
|
const char* name = pnames + shdr.get_sh_name();
|
|
this->deferred_layout_relocs_.push_back(
|
|
Deferred_layout(i, name, pshdr, 0, elfcpp::SHT_NULL));
|
|
out_sections[i] = reinterpret_cast<Output_section*>(2);
|
|
out_section_offsets[i] = invalid_address;
|
|
continue;
|
|
}
|
|
if (data_section == NULL)
|
|
{
|
|
out_sections[i] = NULL;
|
|
out_section_offsets[i] = invalid_address;
|
|
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);
|
|
out_sections[i] = os;
|
|
out_section_offsets[i] = invalid_address;
|
|
}
|
|
|
|
// Handle the .eh_frame sections at the end.
|
|
gold_assert(!is_gc_pass_one || eh_frame_sections.empty());
|
|
for (std::vector<unsigned int>::const_iterator p = eh_frame_sections.begin();
|
|
p != eh_frame_sections.end();
|
|
++p)
|
|
{
|
|
unsigned int i = *p;
|
|
const unsigned char* pshdr;
|
|
pshdr = section_headers_data + i * This::shdr_size;
|
|
typename This::Shdr shdr(pshdr);
|
|
|
|
this->layout_eh_frame_section(layout,
|
|
symbols_data,
|
|
symbols_size,
|
|
symbol_names_data,
|
|
symbol_names_size,
|
|
i,
|
|
shdr,
|
|
reloc_shndx[i],
|
|
reloc_type[i]);
|
|
}
|
|
|
|
if (is_gc_pass_two)
|
|
{
|
|
delete[] gc_sd->section_headers_data;
|
|
delete[] gc_sd->section_names_data;
|
|
delete[] gc_sd->symbols_data;
|
|
delete[] gc_sd->symbol_names_data;
|
|
this->set_symbols_data(NULL);
|
|
}
|
|
else
|
|
{
|
|
delete sd->section_headers;
|
|
sd->section_headers = NULL;
|
|
delete sd->section_names;
|
|
sd->section_names = NULL;
|
|
}
|
|
}
|
|
|
|
// Layout sections whose layout was deferred while waiting for
|
|
// input files from a plugin.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_layout_deferred_sections(Layout* layout)
|
|
{
|
|
typename std::vector<Deferred_layout>::iterator deferred;
|
|
|
|
for (deferred = this->deferred_layout_.begin();
|
|
deferred != this->deferred_layout_.end();
|
|
++deferred)
|
|
{
|
|
typename This::Shdr shdr(deferred->shdr_data_);
|
|
// If the section is not included, it is because the garbage collector
|
|
// decided it is not needed. Avoid reverting that decision.
|
|
if (!this->is_section_included(deferred->shndx_))
|
|
continue;
|
|
|
|
if (parameters->options().relocatable()
|
|
|| deferred->name_ != ".eh_frame"
|
|
|| !this->check_eh_frame_flags(&shdr))
|
|
this->layout_section(layout, deferred->shndx_, deferred->name_.c_str(),
|
|
shdr, deferred->reloc_shndx_,
|
|
deferred->reloc_type_);
|
|
else
|
|
{
|
|
// Reading the symbols again here may be slow.
|
|
Read_symbols_data sd;
|
|
this->read_symbols(&sd);
|
|
this->layout_eh_frame_section(layout,
|
|
sd.symbols->data(),
|
|
sd.symbols_size,
|
|
sd.symbol_names->data(),
|
|
sd.symbol_names_size,
|
|
deferred->shndx_,
|
|
shdr,
|
|
deferred->reloc_shndx_,
|
|
deferred->reloc_type_);
|
|
}
|
|
}
|
|
|
|
this->deferred_layout_.clear();
|
|
|
|
// Now handle the deferred relocation sections.
|
|
|
|
Output_sections& out_sections(this->output_sections());
|
|
std::vector<Address>& out_section_offsets(this->section_offsets());
|
|
|
|
for (deferred = this->deferred_layout_relocs_.begin();
|
|
deferred != this->deferred_layout_relocs_.end();
|
|
++deferred)
|
|
{
|
|
unsigned int shndx = deferred->shndx_;
|
|
typename This::Shdr shdr(deferred->shdr_data_);
|
|
unsigned int data_shndx = this->adjust_shndx(shdr.get_sh_info());
|
|
|
|
Output_section* data_section = out_sections[data_shndx];
|
|
if (data_section == NULL)
|
|
{
|
|
out_sections[shndx] = NULL;
|
|
out_section_offsets[shndx] = invalid_address;
|
|
continue;
|
|
}
|
|
|
|
Relocatable_relocs* rr = new Relocatable_relocs();
|
|
this->set_relocatable_relocs(shndx, rr);
|
|
|
|
Output_section* os = layout->layout_reloc(this, shndx, shdr,
|
|
data_section, rr);
|
|
out_sections[shndx] = os;
|
|
out_section_offsets[shndx] = invalid_address;
|
|
}
|
|
}
|
|
|
|
// Add the symbols to the symbol table.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_add_symbols(Symbol_table* symtab,
|
|
Read_symbols_data* sd,
|
|
Layout*)
|
|
{
|
|
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_,
|
|
&this->defined_count_);
|
|
|
|
delete sd->symbols;
|
|
sd->symbols = NULL;
|
|
delete sd->symbol_names;
|
|
sd->symbol_names = NULL;
|
|
}
|
|
|
|
// Find out if this object, that is a member of a lib group, should be included
|
|
// in the link. We check every symbol defined by this object. If the symbol
|
|
// table has a strong undefined reference to that symbol, we have to include
|
|
// the object.
|
|
|
|
template<int size, bool big_endian>
|
|
Archive::Should_include
|
|
Sized_relobj_file<size, big_endian>::do_should_include_member(
|
|
Symbol_table* symtab,
|
|
Layout* layout,
|
|
Read_symbols_data* sd,
|
|
std::string* why)
|
|
{
|
|
char* tmpbuf = NULL;
|
|
size_t tmpbuflen = 0;
|
|
const char* sym_names =
|
|
reinterpret_cast<const char*>(sd->symbol_names->data());
|
|
const unsigned char* syms =
|
|
sd->symbols->data() + sd->external_symbols_offset;
|
|
const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
|
|
size_t symcount = ((sd->symbols_size - sd->external_symbols_offset)
|
|
/ sym_size);
|
|
|
|
const unsigned char* p = syms;
|
|
|
|
for (size_t i = 0; i < symcount; ++i, p += sym_size)
|
|
{
|
|
elfcpp::Sym<size, big_endian> sym(p);
|
|
unsigned int st_shndx = sym.get_st_shndx();
|
|
if (st_shndx == elfcpp::SHN_UNDEF)
|
|
continue;
|
|
|
|
unsigned int st_name = sym.get_st_name();
|
|
const char* name = sym_names + st_name;
|
|
Symbol* symbol;
|
|
Archive::Should_include t = Archive::should_include_member(symtab,
|
|
layout,
|
|
name,
|
|
&symbol, why,
|
|
&tmpbuf,
|
|
&tmpbuflen);
|
|
if (t == Archive::SHOULD_INCLUDE_YES)
|
|
{
|
|
if (tmpbuf != NULL)
|
|
free(tmpbuf);
|
|
return t;
|
|
}
|
|
}
|
|
if (tmpbuf != NULL)
|
|
free(tmpbuf);
|
|
return Archive::SHOULD_INCLUDE_UNKNOWN;
|
|
}
|
|
|
|
// Iterate over global defined symbols, calling a visitor class V for each.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_for_all_global_symbols(
|
|
Read_symbols_data* sd,
|
|
Library_base::Symbol_visitor_base* v)
|
|
{
|
|
const char* sym_names =
|
|
reinterpret_cast<const char*>(sd->symbol_names->data());
|
|
const unsigned char* syms =
|
|
sd->symbols->data() + sd->external_symbols_offset;
|
|
const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
|
|
size_t symcount = ((sd->symbols_size - sd->external_symbols_offset)
|
|
/ sym_size);
|
|
const unsigned char* p = syms;
|
|
|
|
for (size_t i = 0; i < symcount; ++i, p += sym_size)
|
|
{
|
|
elfcpp::Sym<size, big_endian> sym(p);
|
|
if (sym.get_st_shndx() != elfcpp::SHN_UNDEF)
|
|
v->visit(sym_names + sym.get_st_name());
|
|
}
|
|
}
|
|
|
|
// Return whether the local symbol SYMNDX has a PLT offset.
|
|
|
|
template<int size, bool big_endian>
|
|
bool
|
|
Sized_relobj_file<size, big_endian>::local_has_plt_offset(
|
|
unsigned int symndx) const
|
|
{
|
|
typename Local_plt_offsets::const_iterator p =
|
|
this->local_plt_offsets_.find(symndx);
|
|
return p != this->local_plt_offsets_.end();
|
|
}
|
|
|
|
// Get the PLT offset of a local symbol.
|
|
|
|
template<int size, bool big_endian>
|
|
unsigned int
|
|
Sized_relobj_file<size, big_endian>::do_local_plt_offset(
|
|
unsigned int symndx) const
|
|
{
|
|
typename Local_plt_offsets::const_iterator p =
|
|
this->local_plt_offsets_.find(symndx);
|
|
gold_assert(p != this->local_plt_offsets_.end());
|
|
return p->second;
|
|
}
|
|
|
|
// Set the PLT offset of a local symbol.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::set_local_plt_offset(
|
|
unsigned int symndx, unsigned int plt_offset)
|
|
{
|
|
std::pair<typename Local_plt_offsets::iterator, bool> ins =
|
|
this->local_plt_offsets_.insert(std::make_pair(symndx, plt_offset));
|
|
gold_assert(ins.second);
|
|
}
|
|
|
|
// 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_file<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 Output_sections& out_sections(this->output_sections());
|
|
unsigned int shnum = this->shnum();
|
|
unsigned int count = 0;
|
|
unsigned int dyncount = 0;
|
|
// Skip the first, dummy, symbol.
|
|
psyms += sym_size;
|
|
bool strip_all = parameters->options().strip_all();
|
|
bool discard_all = parameters->options().discard_all();
|
|
bool discard_locals = parameters->options().discard_locals();
|
|
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();
|
|
else if (sym.get_st_type() == elfcpp::STT_GNU_IFUNC)
|
|
lv.set_is_ifunc_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 && out_sections[shndx] == NULL)
|
|
|| shndx == this->discarded_eh_frame_shndx_)
|
|
{
|
|
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;
|
|
}
|
|
|
|
const char* name = pnames + sym.get_st_name();
|
|
|
|
// If needed, add the symbol to the dynamic symbol table string pool.
|
|
if (lv.needs_output_dynsym_entry())
|
|
{
|
|
dynpool->add(name, true, NULL);
|
|
++dyncount;
|
|
}
|
|
|
|
if (strip_all
|
|
|| (discard_all && lv.may_be_discarded_from_output_symtab()))
|
|
{
|
|
lv.set_no_output_symtab_entry();
|
|
continue;
|
|
}
|
|
|
|
// If --discard-locals option is used, discard all temporary local
|
|
// symbols. These symbols start with system-specific local label
|
|
// prefixes, typically .L for ELF system. We want to be compatible
|
|
// with GNU ld so here we essentially use the same check in
|
|
// bfd_is_local_label(). The code is different because we already
|
|
// know that:
|
|
//
|
|
// - the symbol is local and thus cannot have global or weak binding.
|
|
// - the symbol is not a section symbol.
|
|
// - the symbol has a name.
|
|
//
|
|
// We do not discard a symbol if it needs a dynamic symbol entry.
|
|
if (discard_locals
|
|
&& sym.get_st_type() != elfcpp::STT_FILE
|
|
&& !lv.needs_output_dynsym_entry()
|
|
&& lv.may_be_discarded_from_output_symtab()
|
|
&& parameters->target().is_local_label_name(name))
|
|
{
|
|
lv.set_no_output_symtab_entry();
|
|
continue;
|
|
}
|
|
|
|
// Discard the local symbol if -retain_symbols_file is specified
|
|
// and the local symbol is not in that file.
|
|
if (!parameters->options().should_retain_symbol(name))
|
|
{
|
|
lv.set_no_output_symtab_entry();
|
|
continue;
|
|
}
|
|
|
|
// Add the symbol to the symbol table string pool.
|
|
pool->add(name, true, NULL);
|
|
++count;
|
|
}
|
|
|
|
this->output_local_symbol_count_ = count;
|
|
this->output_local_dynsym_count_ = dyncount;
|
|
}
|
|
|
|
// Compute the final value of a local symbol.
|
|
|
|
template<int size, bool big_endian>
|
|
typename Sized_relobj_file<size, big_endian>::Compute_final_local_value_status
|
|
Sized_relobj_file<size, big_endian>::compute_final_local_value_internal(
|
|
unsigned int r_sym,
|
|
const Symbol_value<size>* lv_in,
|
|
Symbol_value<size>* lv_out,
|
|
bool relocatable,
|
|
const Output_sections& out_sections,
|
|
const std::vector<Address>& out_offsets,
|
|
const Symbol_table* symtab)
|
|
{
|
|
// We are going to overwrite *LV_OUT, if it has a merged symbol value,
|
|
// we may have a memory leak.
|
|
gold_assert(lv_out->has_output_value());
|
|
|
|
bool is_ordinary;
|
|
unsigned int shndx = lv_in->input_shndx(&is_ordinary);
|
|
|
|
// Set the output symbol value.
|
|
|
|
if (!is_ordinary)
|
|
{
|
|
if (shndx == elfcpp::SHN_ABS || Symbol::is_common_shndx(shndx))
|
|
lv_out->set_output_value(lv_in->input_value());
|
|
else
|
|
{
|
|
this->error(_("unknown section index %u for local symbol %u"),
|
|
shndx, r_sym);
|
|
lv_out->set_output_value(0);
|
|
return This::CFLV_ERROR;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (shndx >= this->shnum())
|
|
{
|
|
this->error(_("local symbol %u section index %u out of range"),
|
|
r_sym, shndx);
|
|
lv_out->set_output_value(0);
|
|
return This::CFLV_ERROR;
|
|
}
|
|
|
|
Output_section* os = out_sections[shndx];
|
|
Address secoffset = out_offsets[shndx];
|
|
if (symtab->is_section_folded(this, shndx))
|
|
{
|
|
gold_assert(os == NULL && secoffset == invalid_address);
|
|
// Get the os of the section it is folded onto.
|
|
Section_id folded = symtab->icf()->get_folded_section(this,
|
|
shndx);
|
|
gold_assert(folded.first != NULL);
|
|
Sized_relobj_file<size, big_endian>* folded_obj = reinterpret_cast
|
|
<Sized_relobj_file<size, big_endian>*>(folded.first);
|
|
os = folded_obj->output_section(folded.second);
|
|
gold_assert(os != NULL);
|
|
secoffset = folded_obj->get_output_section_offset(folded.second);
|
|
|
|
// This could be a relaxed input section.
|
|
if (secoffset == invalid_address)
|
|
{
|
|
const Output_relaxed_input_section* relaxed_section =
|
|
os->find_relaxed_input_section(folded_obj, folded.second);
|
|
gold_assert(relaxed_section != NULL);
|
|
secoffset = relaxed_section->address() - os->address();
|
|
}
|
|
}
|
|
|
|
if (os == NULL)
|
|
{
|
|
// This local symbol belongs to a section we are discarding.
|
|
// In some cases when applying relocations later, we will
|
|
// attempt to match it to the corresponding kept section,
|
|
// so we leave the input value unchanged here.
|
|
return This::CFLV_DISCARDED;
|
|
}
|
|
else if (secoffset == invalid_address)
|
|
{
|
|
uint64_t start;
|
|
|
|
// This is a SHF_MERGE section or one which otherwise
|
|
// requires special handling.
|
|
if (shndx == this->discarded_eh_frame_shndx_)
|
|
{
|
|
// This local symbol belongs to a discarded .eh_frame
|
|
// section. Just treat it like the case in which
|
|
// os == NULL above.
|
|
gold_assert(this->has_eh_frame_);
|
|
return This::CFLV_DISCARDED;
|
|
}
|
|
else if (!lv_in->is_section_symbol())
|
|
{
|
|
// This is not a section symbol. We can determine
|
|
// the final value now.
|
|
lv_out->set_output_value(
|
|
os->output_address(this, shndx, lv_in->input_value()));
|
|
}
|
|
else if (!os->find_starting_output_address(this, shndx, &start))
|
|
{
|
|
// This is a section symbol, but apparently not one in a
|
|
// merged section. First check to see if this is a relaxed
|
|
// input section. If so, use its address. Otherwise just
|
|
// use the start of the output section. This happens with
|
|
// relocatable links when the input object has section
|
|
// symbols for arbitrary non-merge sections.
|
|
const Output_section_data* posd =
|
|
os->find_relaxed_input_section(this, shndx);
|
|
if (posd != NULL)
|
|
{
|
|
Address relocatable_link_adjustment =
|
|
relocatable ? os->address() : 0;
|
|
lv_out->set_output_value(posd->address()
|
|
- relocatable_link_adjustment);
|
|
}
|
|
else
|
|
lv_out->set_output_value(os->address());
|
|
}
|
|
else
|
|
{
|
|
// We have to consider the addend to determine the
|
|
// value to use in a relocation. START is the start
|
|
// of this input section. If we are doing a relocatable
|
|
// link, use offset from start output section instead of
|
|
// address.
|
|
Address adjusted_start =
|
|
relocatable ? start - os->address() : start;
|
|
Merged_symbol_value<size>* msv =
|
|
new Merged_symbol_value<size>(lv_in->input_value(),
|
|
adjusted_start);
|
|
lv_out->set_merged_symbol_value(msv);
|
|
}
|
|
}
|
|
else if (lv_in->is_tls_symbol())
|
|
lv_out->set_output_value(os->tls_offset()
|
|
+ secoffset
|
|
+ lv_in->input_value());
|
|
else
|
|
lv_out->set_output_value((relocatable ? 0 : os->address())
|
|
+ secoffset
|
|
+ lv_in->input_value());
|
|
}
|
|
return This::CFLV_OK;
|
|
}
|
|
|
|
// Compute final local symbol value. R_SYM is the index of a local
|
|
// symbol in symbol table. LV points to a symbol value, which is
|
|
// expected to hold the input value and to be over-written by the
|
|
// final value. SYMTAB points to a symbol table. Some targets may want
|
|
// to know would-be-finalized local symbol values in relaxation.
|
|
// Hence we provide this method. Since this method updates *LV, a
|
|
// callee should make a copy of the original local symbol value and
|
|
// use the copy instead of modifying an object's local symbols before
|
|
// everything is finalized. The caller should also free up any allocated
|
|
// memory in the return value in *LV.
|
|
template<int size, bool big_endian>
|
|
typename Sized_relobj_file<size, big_endian>::Compute_final_local_value_status
|
|
Sized_relobj_file<size, big_endian>::compute_final_local_value(
|
|
unsigned int r_sym,
|
|
const Symbol_value<size>* lv_in,
|
|
Symbol_value<size>* lv_out,
|
|
const Symbol_table* symtab)
|
|
{
|
|
// This is just a wrapper of compute_final_local_value_internal.
|
|
const bool relocatable = parameters->options().relocatable();
|
|
const Output_sections& out_sections(this->output_sections());
|
|
const std::vector<Address>& out_offsets(this->section_offsets());
|
|
return this->compute_final_local_value_internal(r_sym, lv_in, lv_out,
|
|
relocatable, out_sections,
|
|
out_offsets, symtab);
|
|
}
|
|
|
|
// 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_file<size, big_endian>::do_finalize_local_symbols(
|
|
unsigned int index,
|
|
off_t off,
|
|
Symbol_table* symtab)
|
|
{
|
|
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 bool relocatable = parameters->options().relocatable();
|
|
const Output_sections& out_sections(this->output_sections());
|
|
const std::vector<Address>& out_offsets(this->section_offsets());
|
|
|
|
for (unsigned int i = 1; i < loccount; ++i)
|
|
{
|
|
Symbol_value<size>* lv = &this->local_values_[i];
|
|
|
|
Compute_final_local_value_status cflv_status =
|
|
this->compute_final_local_value_internal(i, lv, lv, relocatable,
|
|
out_sections, out_offsets,
|
|
symtab);
|
|
switch (cflv_status)
|
|
{
|
|
case CFLV_OK:
|
|
if (!lv->is_output_symtab_index_set())
|
|
{
|
|
lv->set_output_symtab_index(index);
|
|
++index;
|
|
}
|
|
break;
|
|
case CFLV_DISCARDED:
|
|
case CFLV_ERROR:
|
|
// Do nothing.
|
|
break;
|
|
default:
|
|
gold_unreachable();
|
|
}
|
|
}
|
|
return index;
|
|
}
|
|
|
|
// Set the output dynamic symbol table indexes for the local variables.
|
|
|
|
template<int size, bool big_endian>
|
|
unsigned int
|
|
Sized_relobj_file<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_file<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_;
|
|
}
|
|
|
|
// If Symbols_data is not NULL get the section flags from here otherwise
|
|
// get it from the file.
|
|
|
|
template<int size, bool big_endian>
|
|
uint64_t
|
|
Sized_relobj_file<size, big_endian>::do_section_flags(unsigned int shndx)
|
|
{
|
|
Symbols_data* sd = this->get_symbols_data();
|
|
if (sd != NULL)
|
|
{
|
|
const unsigned char* pshdrs = sd->section_headers_data
|
|
+ This::shdr_size * shndx;
|
|
typename This::Shdr shdr(pshdrs);
|
|
return shdr.get_sh_flags();
|
|
}
|
|
// If sd is NULL, read the section header from the file.
|
|
return this->elf_file_.section_flags(shndx);
|
|
}
|
|
|
|
// Get the section's ent size from Symbols_data. Called by get_section_contents
|
|
// in icf.cc
|
|
|
|
template<int size, bool big_endian>
|
|
uint64_t
|
|
Sized_relobj_file<size, big_endian>::do_section_entsize(unsigned int shndx)
|
|
{
|
|
Symbols_data* sd = this->get_symbols_data();
|
|
gold_assert(sd != NULL);
|
|
|
|
const unsigned char* pshdrs = sd->section_headers_data
|
|
+ This::shdr_size * shndx;
|
|
typename This::Shdr shdr(pshdrs);
|
|
return shdr.get_sh_entsize();
|
|
}
|
|
|
|
// Write out the local symbols.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<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,
|
|
off_t symtab_off)
|
|
{
|
|
const bool strip_all = parameters->options().strip_all();
|
|
if (strip_all)
|
|
{
|
|
if (this->output_local_dynsym_count_ == 0)
|
|
return;
|
|
this->output_local_symbol_count_ = 0;
|
|
}
|
|
|
|
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(symtab_off + 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 Output_sections out_sections(this->output_sections());
|
|
|
|
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 < out_sections.size());
|
|
if (out_sections[st_shndx] == NULL)
|
|
continue;
|
|
st_shndx = out_sections[st_shndx]->out_shndx();
|
|
if (st_shndx >= elfcpp::SHN_LORESERVE)
|
|
{
|
|
if (lv.has_output_symtab_entry())
|
|
symtab_xindex->add(lv.output_symtab_index(), st_shndx);
|
|
if (lv.has_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 (lv.has_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.has_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(symtab_off + 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_file<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;
|
|
}
|
|
|
|
// Look for a kept section corresponding to the given discarded section,
|
|
// and return its output address. This is used only for relocations in
|
|
// debugging sections. If we can't find the kept section, return 0.
|
|
|
|
template<int size, bool big_endian>
|
|
typename Sized_relobj_file<size, big_endian>::Address
|
|
Sized_relobj_file<size, big_endian>::map_to_kept_section(
|
|
unsigned int shndx,
|
|
bool* found) const
|
|
{
|
|
Relobj* kept_object;
|
|
unsigned int kept_shndx;
|
|
if (this->get_kept_comdat_section(shndx, &kept_object, &kept_shndx))
|
|
{
|
|
Sized_relobj_file<size, big_endian>* kept_relobj =
|
|
static_cast<Sized_relobj_file<size, big_endian>*>(kept_object);
|
|
Output_section* os = kept_relobj->output_section(kept_shndx);
|
|
Address offset = kept_relobj->get_output_section_offset(kept_shndx);
|
|
if (os != NULL && offset != invalid_address)
|
|
{
|
|
*found = true;
|
|
return os->address() + offset;
|
|
}
|
|
}
|
|
*found = false;
|
|
return 0;
|
|
}
|
|
|
|
// Get symbol counts.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_get_global_symbol_counts(
|
|
const Symbol_table*,
|
|
size_t* defined,
|
|
size_t* used) const
|
|
{
|
|
*defined = this->defined_count_;
|
|
size_t count = 0;
|
|
for (typename Symbols::const_iterator p = this->symbols_.begin();
|
|
p != this->symbols_.end();
|
|
++p)
|
|
if (*p != NULL
|
|
&& (*p)->source() == Symbol::FROM_OBJECT
|
|
&& (*p)->object() == this
|
|
&& (*p)->is_defined())
|
|
++count;
|
|
*used = count;
|
|
}
|
|
|
|
// Return a view of the decompressed contents of a section. Set *PLEN
|
|
// to the size. Set *IS_NEW to true if the contents need to be freed
|
|
// by the caller.
|
|
|
|
template<int size, bool big_endian>
|
|
const unsigned char*
|
|
Sized_relobj_file<size, big_endian>::do_decompressed_section_contents(
|
|
unsigned int shndx,
|
|
section_size_type* plen,
|
|
bool* is_new)
|
|
{
|
|
section_size_type buffer_size;
|
|
const unsigned char* buffer = this->section_contents(shndx, &buffer_size,
|
|
false);
|
|
|
|
if (this->compressed_sections_ == NULL)
|
|
{
|
|
*plen = buffer_size;
|
|
*is_new = false;
|
|
return buffer;
|
|
}
|
|
|
|
Compressed_section_map::const_iterator p =
|
|
this->compressed_sections_->find(shndx);
|
|
if (p == this->compressed_sections_->end())
|
|
{
|
|
*plen = buffer_size;
|
|
*is_new = false;
|
|
return buffer;
|
|
}
|
|
|
|
section_size_type uncompressed_size = p->second.size;
|
|
if (p->second.contents != NULL)
|
|
{
|
|
*plen = uncompressed_size;
|
|
*is_new = false;
|
|
return p->second.contents;
|
|
}
|
|
|
|
unsigned char* uncompressed_data = new unsigned char[uncompressed_size];
|
|
if (!decompress_input_section(buffer,
|
|
buffer_size,
|
|
uncompressed_data,
|
|
uncompressed_size))
|
|
this->error(_("could not decompress section %s"),
|
|
this->do_section_name(shndx).c_str());
|
|
|
|
// We could cache the results in p->second.contents and store
|
|
// false in *IS_NEW, but build_compressed_section_map() would
|
|
// have done so if it had expected it to be profitable. If
|
|
// we reach this point, we expect to need the contents only
|
|
// once in this pass.
|
|
*plen = uncompressed_size;
|
|
*is_new = true;
|
|
return uncompressed_data;
|
|
}
|
|
|
|
// Discard any buffers of uncompressed sections. This is done
|
|
// at the end of the Add_symbols task.
|
|
|
|
template<int size, bool big_endian>
|
|
void
|
|
Sized_relobj_file<size, big_endian>::do_discard_decompressed_sections()
|
|
{
|
|
if (this->compressed_sections_ == NULL)
|
|
return;
|
|
|
|
for (Compressed_section_map::iterator p = this->compressed_sections_->begin();
|
|
p != this->compressed_sections_->end();
|
|
++p)
|
|
{
|
|
if (p->second.contents != NULL)
|
|
{
|
|
delete[] p->second.contents;
|
|
p->second.contents = NULL;
|
|
}
|
|
}
|
|
}
|
|
|
|
// 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)
|
|
{
|
|
// 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);
|
|
}
|
|
|
|
// Add this object to the cross-referencer if requested.
|
|
if (parameters->options().user_set_print_symbol_counts()
|
|
|| parameters->options().cref())
|
|
{
|
|
if (this->cref_ == NULL)
|
|
this->cref_ = new Cref();
|
|
this->cref_->add_object(obj);
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
// For each dynamic object, record whether we've seen all of its
|
|
// explicit dependencies.
|
|
|
|
void
|
|
Input_objects::check_dynamic_dependencies() const
|
|
{
|
|
bool issued_copy_dt_needed_error = false;
|
|
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;
|
|
Dynobj::Needed::const_iterator pneeded;
|
|
for (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);
|
|
|
|
// --copy-dt-needed-entries aka --add-needed is a GNU ld option
|
|
// that gold does not support. However, they cause no trouble
|
|
// unless there is a DT_NEEDED entry that we don't know about;
|
|
// warn only in that case.
|
|
if (!found_all
|
|
&& !issued_copy_dt_needed_error
|
|
&& (parameters->options().copy_dt_needed_entries()
|
|
|| parameters->options().add_needed()))
|
|
{
|
|
const char* optname;
|
|
if (parameters->options().copy_dt_needed_entries())
|
|
optname = "--copy-dt-needed-entries";
|
|
else
|
|
optname = "--add-needed";
|
|
gold_error(_("%s is not supported but is required for %s in %s"),
|
|
optname, (*pneeded).c_str(), (*p)->name().c_str());
|
|
issued_copy_dt_needed_error = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Start processing an archive.
|
|
|
|
void
|
|
Input_objects::archive_start(Archive* archive)
|
|
{
|
|
if (parameters->options().user_set_print_symbol_counts()
|
|
|| parameters->options().cref())
|
|
{
|
|
if (this->cref_ == NULL)
|
|
this->cref_ = new Cref();
|
|
this->cref_->add_archive_start(archive);
|
|
}
|
|
}
|
|
|
|
// Stop processing an archive.
|
|
|
|
void
|
|
Input_objects::archive_stop(Archive* archive)
|
|
{
|
|
if (parameters->options().user_set_print_symbol_counts()
|
|
|| parameters->options().cref())
|
|
this->cref_->add_archive_stop(archive);
|
|
}
|
|
|
|
// Print symbol counts
|
|
|
|
void
|
|
Input_objects::print_symbol_counts(const Symbol_table* symtab) const
|
|
{
|
|
if (parameters->options().user_set_print_symbol_counts()
|
|
&& this->cref_ != NULL)
|
|
this->cref_->print_symbol_counts(symtab);
|
|
}
|
|
|
|
// Print a cross reference table.
|
|
|
|
void
|
|
Input_objects::print_cref(const Symbol_table* symtab, FILE* f) const
|
|
{
|
|
if (parameters->options().cref() && this->cref_ != NULL)
|
|
this->cref_->print_cref(symtab, f);
|
|
}
|
|
|
|
// Relocate_info methods.
|
|
|
|
// Return a string describing the location of a relocation when file
|
|
// and lineno information is not available. 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
|
|
{
|
|
Sized_dwarf_line_info<size, big_endian> line_info(this->object);
|
|
std::string ret = line_info.addr2line(this->data_shndx, offset, NULL);
|
|
if (!ret.empty())
|
|
return ret;
|
|
|
|
ret = this->object->name();
|
|
|
|
Symbol_location_info info;
|
|
if (this->object->get_symbol_location_info(this->data_shndx, offset, &info))
|
|
{
|
|
if (!info.source_file.empty())
|
|
{
|
|
ret += ":";
|
|
ret += info.source_file;
|
|
}
|
|
size_t len = info.enclosing_symbol_name.length() + 100;
|
|
char* buf = new char[len];
|
|
snprintf(buf, len, _(":function %s"),
|
|
info.enclosing_symbol_name.c_str());
|
|
ret += buf;
|
|
delete[] buf;
|
|
return ret;
|
|
}
|
|
|
|
ret += "(";
|
|
ret += this->object->section_name(this->data_shndx);
|
|
char buf[100];
|
|
snprintf(buf, sizeof buf, "+0x%lx)", static_cast<long>(offset));
|
|
ret += buf;
|
|
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,
|
|
bool* punconfigured)
|
|
{
|
|
Target* target = select_target(ehdr.get_e_machine(), size, big_endian,
|
|
ehdr.get_e_ident()[elfcpp::EI_OSABI],
|
|
ehdr.get_e_ident()[elfcpp::EI_ABIVERSION]);
|
|
if (target == NULL)
|
|
gold_fatal(_("%s: unsupported ELF machine number %d"),
|
|
name.c_str(), ehdr.get_e_machine());
|
|
|
|
if (!parameters->target_valid())
|
|
set_parameters_target(target);
|
|
else if (target != ¶meters->target())
|
|
{
|
|
if (punconfigured != NULL)
|
|
*punconfigured = true;
|
|
else
|
|
gold_error(_("%s: incompatible target"), name.c_str());
|
|
return NULL;
|
|
}
|
|
|
|
return target->make_elf_object<size, big_endian>(name, input_file, offset,
|
|
ehdr);
|
|
}
|
|
|
|
} // End anonymous namespace.
|
|
|
|
namespace gold
|
|
{
|
|
|
|
// Return whether INPUT_FILE is an ELF object.
|
|
|
|
bool
|
|
is_elf_object(Input_file* input_file, off_t offset,
|
|
const unsigned char** start, int* read_size)
|
|
{
|
|
off_t filesize = input_file->file().filesize();
|
|
int want = elfcpp::Elf_recognizer::max_header_size;
|
|
if (filesize - offset < want)
|
|
want = filesize - offset;
|
|
|
|
const unsigned char* p = input_file->file().get_view(offset, 0, want,
|
|
true, false);
|
|
*start = p;
|
|
*read_size = want;
|
|
|
|
return elfcpp::Elf_recognizer::is_elf_file(p, want);
|
|
}
|
|
|
|
// 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,
|
|
bool* punconfigured)
|
|
{
|
|
if (punconfigured != NULL)
|
|
*punconfigured = false;
|
|
|
|
std::string error;
|
|
bool big_endian = false;
|
|
int size = 0;
|
|
if (!elfcpp::Elf_recognizer::is_valid_header(p, bytes, &size,
|
|
&big_endian, &error))
|
|
{
|
|
gold_error(_("%s: %s"), name.c_str(), error.c_str());
|
|
return NULL;
|
|
}
|
|
|
|
if (size == 32)
|
|
{
|
|
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, punconfigured);
|
|
#else
|
|
if (punconfigured != NULL)
|
|
*punconfigured = true;
|
|
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, punconfigured);
|
|
#else
|
|
if (punconfigured != NULL)
|
|
*punconfigured = true;
|
|
else
|
|
gold_error(_("%s: not configured to support "
|
|
"32-bit little-endian object"),
|
|
name.c_str());
|
|
return NULL;
|
|
#endif
|
|
}
|
|
}
|
|
else if (size == 64)
|
|
{
|
|
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, punconfigured);
|
|
#else
|
|
if (punconfigured != NULL)
|
|
*punconfigured = true;
|
|
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, punconfigured);
|
|
#else
|
|
if (punconfigured != NULL)
|
|
*punconfigured = true;
|
|
else
|
|
gold_error(_("%s: not configured to support "
|
|
"64-bit little-endian object"),
|
|
name.c_str());
|
|
return NULL;
|
|
#endif
|
|
}
|
|
}
|
|
else
|
|
gold_unreachable();
|
|
}
|
|
|
|
// 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_file<32, false>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
class Sized_relobj_file<32, true>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
class Sized_relobj_file<64, false>;
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
class Sized_relobj_file<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
|
|
|
|
#ifdef HAVE_TARGET_32_LITTLE
|
|
template
|
|
void
|
|
Xindex::initialize_symtab_xindex<32, false>(Object*, unsigned int);
|
|
|
|
template
|
|
void
|
|
Xindex::read_symtab_xindex<32, false>(Object*, unsigned int,
|
|
const unsigned char*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_32_BIG
|
|
template
|
|
void
|
|
Xindex::initialize_symtab_xindex<32, true>(Object*, unsigned int);
|
|
|
|
template
|
|
void
|
|
Xindex::read_symtab_xindex<32, true>(Object*, unsigned int,
|
|
const unsigned char*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_LITTLE
|
|
template
|
|
void
|
|
Xindex::initialize_symtab_xindex<64, false>(Object*, unsigned int);
|
|
|
|
template
|
|
void
|
|
Xindex::read_symtab_xindex<64, false>(Object*, unsigned int,
|
|
const unsigned char*);
|
|
#endif
|
|
|
|
#ifdef HAVE_TARGET_64_BIG
|
|
template
|
|
void
|
|
Xindex::initialize_symtab_xindex<64, true>(Object*, unsigned int);
|
|
|
|
template
|
|
void
|
|
Xindex::read_symtab_xindex<64, true>(Object*, unsigned int,
|
|
const unsigned char*);
|
|
#endif
|
|
|
|
} // End namespace gold.
|