mirror of
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d1bddd3c4b
2014-05-02 Cary Coutant <ccoutant@google.com> * defstd.cc (in_segment): Define __ehdr_start here... * layout.cc (Layout::finalize): ...Instead of here. Set the output segment when known. * resolve.cc (Symbol::override_base_with_special): Remember the original binding. * symtab.cc (Symbol::set_output_segment): New function. (Symbol::set_undefined): New function. * symtab.h (Symbol::is_weak_undefined): Check original undef binding. (Symbol::is_strong_undefined): New function. (Symbol::set_output_segment): New function. (Symbol::set_undefined): New function. * target-reloc.h (is_strong_undefined): Remove. (issue_undefined_symbol_error): Call Symbol::is_weak_undefined. Check for hidden undefs. (relocate_section): Call Symbol::is_strong_undefined. * testsuite/Makefile.am (ehdr_start_test_1) (ehdr_start_test_2, ehdr_start_test_3) (ehdr_start_test_4, ehdr_start_test_5): New test cases. * testsuite/Makefile.in: Regenerate. * testsuite/ehdr_start_def.cc: New source file. * testsuite/ehdr_start_test.cc: New source file. * testsuite/ehdr_start_test.t: New linker script. * testsuite/ehdr_start_test_4.sh: New shell script.
833 lines
27 KiB
C++
833 lines
27 KiB
C++
// target-reloc.h -- target specific relocation support -*- C++ -*-
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// Copyright (C) 2006-2014 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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#ifndef GOLD_TARGET_RELOC_H
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#define GOLD_TARGET_RELOC_H
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#include "elfcpp.h"
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#include "symtab.h"
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#include "object.h"
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#include "reloc.h"
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#include "reloc-types.h"
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namespace gold
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{
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// This function implements the generic part of reloc scanning. The
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// template parameter Scan must be a class type which provides two
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// functions: local() and global(). Those functions implement the
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// machine specific part of scanning. We do it this way to
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// avoid making a function call for each relocation, and to avoid
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// repeating the generic code for each target.
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template<int size, bool big_endian, typename Target_type, int sh_type,
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typename Scan>
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inline void
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scan_relocs(
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Symbol_table* symtab,
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Layout* layout,
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Target_type* target,
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Sized_relobj_file<size, big_endian>* object,
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unsigned int data_shndx,
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const unsigned char* prelocs,
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size_t reloc_count,
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Output_section* output_section,
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bool needs_special_offset_handling,
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size_t local_count,
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const unsigned char* plocal_syms)
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{
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typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
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const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
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const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
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Scan scan;
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for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
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{
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Reltype reloc(prelocs);
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if (needs_special_offset_handling
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&& !output_section->is_input_address_mapped(object, data_shndx,
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reloc.get_r_offset()))
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continue;
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typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
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unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
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unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
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if (r_sym < local_count)
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{
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gold_assert(plocal_syms != NULL);
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typename elfcpp::Sym<size, big_endian> lsym(plocal_syms
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+ r_sym * sym_size);
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unsigned int shndx = lsym.get_st_shndx();
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bool is_ordinary;
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shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
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// If RELOC is a relocation against a local symbol in a
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// section we are discarding then we can ignore it. It will
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// eventually become a reloc against the value zero.
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//
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// FIXME: We should issue a warning if this is an
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// allocated section; is this the best place to do it?
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//
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// FIXME: The old GNU linker would in some cases look
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// for the linkonce section which caused this section to
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// be discarded, and, if the other section was the same
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// size, change the reloc to refer to the other section.
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// That seems risky and weird to me, and I don't know of
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// any case where it is actually required.
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bool is_discarded = (is_ordinary
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&& shndx != elfcpp::SHN_UNDEF
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&& !object->is_section_included(shndx)
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&& !symtab->is_section_folded(object, shndx));
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scan.local(symtab, layout, target, object, data_shndx,
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output_section, reloc, r_type, lsym, is_discarded);
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}
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else
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{
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Symbol* gsym = object->global_symbol(r_sym);
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gold_assert(gsym != NULL);
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if (gsym->is_forwarder())
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gsym = symtab->resolve_forwards(gsym);
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scan.global(symtab, layout, target, object, data_shndx,
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output_section, reloc, r_type, gsym);
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}
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}
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}
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// Behavior for relocations to discarded comdat sections.
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enum Comdat_behavior
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{
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CB_UNDETERMINED, // Not yet determined -- need to look at section name.
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CB_PRETEND, // Attempt to map to the corresponding kept section.
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CB_IGNORE, // Ignore the relocation.
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CB_WARNING // Print a warning.
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};
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class Default_comdat_behavior
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{
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public:
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// Decide what the linker should do for relocations that refer to
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// discarded comdat sections. This decision is based on the name of
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// the section being relocated.
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inline Comdat_behavior
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get(const char* name)
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{
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if (Layout::is_debug_info_section(name))
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return CB_PRETEND;
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if (strcmp(name, ".eh_frame") == 0
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|| strcmp(name, ".gcc_except_table") == 0)
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return CB_IGNORE;
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return CB_WARNING;
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}
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};
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// Give an error for a symbol with non-default visibility which is not
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// defined locally.
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inline void
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visibility_error(const Symbol* sym)
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{
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const char* v;
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switch (sym->visibility())
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{
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case elfcpp::STV_INTERNAL:
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v = _("internal");
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break;
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case elfcpp::STV_HIDDEN:
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v = _("hidden");
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break;
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case elfcpp::STV_PROTECTED:
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v = _("protected");
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break;
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default:
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gold_unreachable();
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}
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gold_error(_("%s symbol '%s' is not defined locally"),
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v, sym->name());
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}
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// Return true if we are should issue an error saying that SYM is an
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// undefined symbol. This is called if there is a relocation against
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// SYM.
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inline bool
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issue_undefined_symbol_error(const Symbol* sym)
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{
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// We only report global symbols.
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if (sym == NULL)
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return false;
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// We only report undefined symbols.
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if (!sym->is_undefined() && !sym->is_placeholder())
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return false;
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// We don't report weak symbols.
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if (sym->is_weak_undefined())
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return false;
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// We don't report symbols defined in discarded sections.
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if (sym->is_defined_in_discarded_section())
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return false;
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// If the target defines this symbol, don't report it here.
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if (parameters->target().is_defined_by_abi(sym))
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return false;
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// See if we've been told to ignore whether this symbol is
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// undefined.
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const char* const u = parameters->options().unresolved_symbols();
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if (u != NULL)
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{
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if (strcmp(u, "ignore-all") == 0)
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return false;
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if (strcmp(u, "report-all") == 0)
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return true;
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if (strcmp(u, "ignore-in-object-files") == 0 && !sym->in_dyn())
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return false;
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if (strcmp(u, "ignore-in-shared-libs") == 0 && !sym->in_reg())
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return false;
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}
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// If the symbol is hidden, report it.
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if (sym->visibility() == elfcpp::STV_HIDDEN)
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return true;
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// When creating a shared library, only report unresolved symbols if
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// -z defs was used.
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if (parameters->options().shared() && !parameters->options().defs())
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return false;
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// Otherwise issue a warning.
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return true;
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}
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// This function implements the generic part of relocation processing.
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// The template parameter Relocate must be a class type which provides
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// a single function, relocate(), which implements the machine
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// specific part of a relocation.
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// The template parameter Relocate_comdat_behavior is a class type
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// which provides a single function, get(), which determines what the
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// linker should do for relocations that refer to discarded comdat
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// sections.
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// SIZE is the ELF size: 32 or 64. BIG_ENDIAN is the endianness of
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// the data. SH_TYPE is the section type: SHT_REL or SHT_RELA.
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// RELOCATE implements operator() to do a relocation.
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// PRELOCS points to the relocation data. RELOC_COUNT is the number
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// of relocs. OUTPUT_SECTION is the output section.
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// NEEDS_SPECIAL_OFFSET_HANDLING is true if input offsets need to be
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// mapped to output offsets.
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// VIEW is the section data, VIEW_ADDRESS is its memory address, and
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// VIEW_SIZE is the size. These refer to the input section, unless
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// NEEDS_SPECIAL_OFFSET_HANDLING is true, in which case they refer to
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// the output section.
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// RELOC_SYMBOL_CHANGES is used for -fsplit-stack support. If it is
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// not NULL, it is a vector indexed by relocation index. If that
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// entry is not NULL, it points to a global symbol which used as the
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// symbol for the relocation, ignoring the symbol index in the
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// relocation.
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template<int size, bool big_endian, typename Target_type, int sh_type,
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typename Relocate,
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typename Relocate_comdat_behavior>
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inline void
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relocate_section(
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const Relocate_info<size, big_endian>* relinfo,
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Target_type* target,
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const unsigned char* prelocs,
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size_t reloc_count,
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Output_section* output_section,
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bool needs_special_offset_handling,
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unsigned char* view,
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typename elfcpp::Elf_types<size>::Elf_Addr view_address,
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section_size_type view_size,
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const Reloc_symbol_changes* reloc_symbol_changes)
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{
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typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
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const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
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Relocate relocate;
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Relocate_comdat_behavior relocate_comdat_behavior;
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Sized_relobj_file<size, big_endian>* object = relinfo->object;
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unsigned int local_count = object->local_symbol_count();
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Comdat_behavior comdat_behavior = CB_UNDETERMINED;
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for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
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{
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Reltype reloc(prelocs);
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section_offset_type offset =
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convert_to_section_size_type(reloc.get_r_offset());
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if (needs_special_offset_handling)
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{
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offset = output_section->output_offset(relinfo->object,
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relinfo->data_shndx,
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offset);
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if (offset == -1)
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continue;
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}
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typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
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unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
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unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
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const Sized_symbol<size>* sym;
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Symbol_value<size> symval;
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const Symbol_value<size> *psymval;
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bool is_defined_in_discarded_section;
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unsigned int shndx;
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if (r_sym < local_count
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&& (reloc_symbol_changes == NULL
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|| (*reloc_symbol_changes)[i] == NULL))
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{
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sym = NULL;
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psymval = object->local_symbol(r_sym);
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// If the local symbol belongs to a section we are discarding,
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// and that section is a debug section, try to find the
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// corresponding kept section and map this symbol to its
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// counterpart in the kept section. The symbol must not
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// correspond to a section we are folding.
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bool is_ordinary;
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shndx = psymval->input_shndx(&is_ordinary);
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is_defined_in_discarded_section =
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(is_ordinary
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&& shndx != elfcpp::SHN_UNDEF
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&& !object->is_section_included(shndx)
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&& !relinfo->symtab->is_section_folded(object, shndx));
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}
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else
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{
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const Symbol* gsym;
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if (reloc_symbol_changes != NULL
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&& (*reloc_symbol_changes)[i] != NULL)
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gsym = (*reloc_symbol_changes)[i];
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else
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{
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gsym = object->global_symbol(r_sym);
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gold_assert(gsym != NULL);
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if (gsym->is_forwarder())
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gsym = relinfo->symtab->resolve_forwards(gsym);
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}
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sym = static_cast<const Sized_symbol<size>*>(gsym);
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if (sym->has_symtab_index() && sym->symtab_index() != -1U)
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symval.set_output_symtab_index(sym->symtab_index());
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else
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symval.set_no_output_symtab_entry();
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symval.set_output_value(sym->value());
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if (gsym->type() == elfcpp::STT_TLS)
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symval.set_is_tls_symbol();
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else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
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symval.set_is_ifunc_symbol();
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psymval = &symval;
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is_defined_in_discarded_section =
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(gsym->is_defined_in_discarded_section()
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&& gsym->is_undefined());
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shndx = 0;
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}
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Symbol_value<size> symval2;
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if (is_defined_in_discarded_section)
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{
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if (comdat_behavior == CB_UNDETERMINED)
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{
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std::string name = object->section_name(relinfo->data_shndx);
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comdat_behavior = relocate_comdat_behavior.get(name.c_str());
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}
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if (comdat_behavior == CB_PRETEND)
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{
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// FIXME: This case does not work for global symbols.
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// We have no place to store the original section index.
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// Fortunately this does not matter for comdat sections,
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// only for sections explicitly discarded by a linker
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// script.
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bool found;
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typename elfcpp::Elf_types<size>::Elf_Addr value =
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object->map_to_kept_section(shndx, &found);
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if (found)
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symval2.set_output_value(value + psymval->input_value());
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else
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symval2.set_output_value(0);
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}
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else
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{
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if (comdat_behavior == CB_WARNING)
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gold_warning_at_location(relinfo, i, offset,
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_("relocation refers to discarded "
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"section"));
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symval2.set_output_value(0);
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}
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symval2.set_no_output_symtab_entry();
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psymval = &symval2;
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}
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// If OFFSET is out of range, still let the target decide to
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// ignore the relocation. Pass in NULL as the VIEW argument so
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// that it can return quickly without trashing an invalid memory
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// address.
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unsigned char *v = view + offset;
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if (offset < 0 || static_cast<section_size_type>(offset) >= view_size)
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v = NULL;
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if (!relocate.relocate(relinfo, target, output_section, i, reloc,
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r_type, sym, psymval, v, view_address + offset,
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view_size))
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continue;
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if (v == NULL)
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{
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gold_error_at_location(relinfo, i, offset,
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_("reloc has bad offset %zu"),
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static_cast<size_t>(offset));
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continue;
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}
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if (issue_undefined_symbol_error(sym))
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gold_undefined_symbol_at_location(sym, relinfo, i, offset);
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else if (sym != NULL
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&& sym->visibility() != elfcpp::STV_DEFAULT
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&& (sym->is_strong_undefined() || sym->is_from_dynobj()))
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visibility_error(sym);
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if (sym != NULL && sym->has_warning())
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relinfo->symtab->issue_warning(sym, relinfo, i, offset);
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}
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}
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// Apply an incremental relocation.
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template<int size, bool big_endian, typename Target_type,
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typename Relocate>
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void
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apply_relocation(const Relocate_info<size, big_endian>* relinfo,
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Target_type* target,
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typename elfcpp::Elf_types<size>::Elf_Addr r_offset,
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unsigned int r_type,
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typename elfcpp::Elf_types<size>::Elf_Swxword r_addend,
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const Symbol* gsym,
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unsigned char* view,
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typename elfcpp::Elf_types<size>::Elf_Addr address,
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section_size_type view_size)
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{
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// Construct the ELF relocation in a temporary buffer.
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const int reloc_size = elfcpp::Elf_sizes<size>::rela_size;
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unsigned char relbuf[reloc_size];
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elfcpp::Rela<size, big_endian> rel(relbuf);
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elfcpp::Rela_write<size, big_endian> orel(relbuf);
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orel.put_r_offset(r_offset);
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orel.put_r_info(elfcpp::elf_r_info<size>(0, r_type));
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orel.put_r_addend(r_addend);
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// Setup a Symbol_value for the global symbol.
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const Sized_symbol<size>* sym = static_cast<const Sized_symbol<size>*>(gsym);
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Symbol_value<size> symval;
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gold_assert(sym->has_symtab_index() && sym->symtab_index() != -1U);
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symval.set_output_symtab_index(sym->symtab_index());
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symval.set_output_value(sym->value());
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if (gsym->type() == elfcpp::STT_TLS)
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symval.set_is_tls_symbol();
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else if (gsym->type() == elfcpp::STT_GNU_IFUNC)
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symval.set_is_ifunc_symbol();
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|
Relocate relocate;
|
|
relocate.relocate(relinfo, target, NULL, -1U, rel, r_type, sym, &symval,
|
|
view + r_offset, address + r_offset, view_size);
|
|
}
|
|
|
|
// This class may be used as a typical class for the
|
|
// Scan_relocatable_reloc parameter to scan_relocatable_relocs. The
|
|
// template parameter Classify_reloc must be a class type which
|
|
// provides a function get_size_for_reloc which returns the number of
|
|
// bytes to which a reloc applies. This class is intended to capture
|
|
// the most typical target behaviour, while still permitting targets
|
|
// to define their own independent class for Scan_relocatable_reloc.
|
|
|
|
template<int sh_type, typename Classify_reloc>
|
|
class Default_scan_relocatable_relocs
|
|
{
|
|
public:
|
|
// Return the strategy to use for a local symbol which is not a
|
|
// section symbol, given the relocation type.
|
|
inline Relocatable_relocs::Reloc_strategy
|
|
local_non_section_strategy(unsigned int r_type, Relobj*, unsigned int r_sym)
|
|
{
|
|
// We assume that relocation type 0 is NONE. Targets which are
|
|
// different must override.
|
|
if (r_type == 0 && r_sym == 0)
|
|
return Relocatable_relocs::RELOC_DISCARD;
|
|
return Relocatable_relocs::RELOC_COPY;
|
|
}
|
|
|
|
// Return the strategy to use for a local symbol which is a section
|
|
// symbol, given the relocation type.
|
|
inline Relocatable_relocs::Reloc_strategy
|
|
local_section_strategy(unsigned int r_type, Relobj* object)
|
|
{
|
|
if (sh_type == elfcpp::SHT_RELA)
|
|
return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA;
|
|
else
|
|
{
|
|
Classify_reloc classify;
|
|
switch (classify.get_size_for_reloc(r_type, object))
|
|
{
|
|
case 0:
|
|
return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0;
|
|
case 1:
|
|
return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1;
|
|
case 2:
|
|
return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2;
|
|
case 4:
|
|
return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4;
|
|
case 8:
|
|
return Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8;
|
|
default:
|
|
gold_unreachable();
|
|
}
|
|
}
|
|
}
|
|
|
|
// Return the strategy to use for a global symbol, given the
|
|
// relocation type, the object, and the symbol index.
|
|
inline Relocatable_relocs::Reloc_strategy
|
|
global_strategy(unsigned int, Relobj*, unsigned int)
|
|
{ return Relocatable_relocs::RELOC_COPY; }
|
|
};
|
|
|
|
// Scan relocs during a relocatable link. This is a default
|
|
// definition which should work for most targets.
|
|
// Scan_relocatable_reloc must name a class type which provides three
|
|
// functions which return a Relocatable_relocs::Reloc_strategy code:
|
|
// global_strategy, local_non_section_strategy, and
|
|
// local_section_strategy. Most targets should be able to use
|
|
// Default_scan_relocatable_relocs as this class.
|
|
|
|
template<int size, bool big_endian, int sh_type,
|
|
typename Scan_relocatable_reloc>
|
|
void
|
|
scan_relocatable_relocs(
|
|
Symbol_table*,
|
|
Layout*,
|
|
Sized_relobj_file<size, big_endian>* object,
|
|
unsigned int data_shndx,
|
|
const unsigned char* prelocs,
|
|
size_t reloc_count,
|
|
Output_section* output_section,
|
|
bool needs_special_offset_handling,
|
|
size_t local_symbol_count,
|
|
const unsigned char* plocal_syms,
|
|
Relocatable_relocs* rr)
|
|
{
|
|
typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
|
|
const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
|
|
const int sym_size = elfcpp::Elf_sizes<size>::sym_size;
|
|
Scan_relocatable_reloc scan;
|
|
|
|
for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
|
|
{
|
|
Reltype reloc(prelocs);
|
|
|
|
Relocatable_relocs::Reloc_strategy strategy;
|
|
|
|
if (needs_special_offset_handling
|
|
&& !output_section->is_input_address_mapped(object, data_shndx,
|
|
reloc.get_r_offset()))
|
|
strategy = Relocatable_relocs::RELOC_DISCARD;
|
|
else
|
|
{
|
|
typename elfcpp::Elf_types<size>::Elf_WXword r_info =
|
|
reloc.get_r_info();
|
|
const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
|
|
const unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
|
|
|
|
if (r_sym >= local_symbol_count)
|
|
strategy = scan.global_strategy(r_type, object, r_sym);
|
|
else
|
|
{
|
|
gold_assert(plocal_syms != NULL);
|
|
typename elfcpp::Sym<size, big_endian> lsym(plocal_syms
|
|
+ r_sym * sym_size);
|
|
unsigned int shndx = lsym.get_st_shndx();
|
|
bool is_ordinary;
|
|
shndx = object->adjust_sym_shndx(r_sym, shndx, &is_ordinary);
|
|
if (is_ordinary
|
|
&& shndx != elfcpp::SHN_UNDEF
|
|
&& !object->is_section_included(shndx))
|
|
{
|
|
// RELOC is a relocation against a local symbol
|
|
// defined in a section we are discarding. Discard
|
|
// the reloc. FIXME: Should we issue a warning?
|
|
strategy = Relocatable_relocs::RELOC_DISCARD;
|
|
}
|
|
else if (lsym.get_st_type() != elfcpp::STT_SECTION)
|
|
strategy = scan.local_non_section_strategy(r_type, object,
|
|
r_sym);
|
|
else
|
|
{
|
|
strategy = scan.local_section_strategy(r_type, object);
|
|
if (strategy != Relocatable_relocs::RELOC_DISCARD)
|
|
object->output_section(shndx)->set_needs_symtab_index();
|
|
}
|
|
|
|
if (strategy == Relocatable_relocs::RELOC_COPY)
|
|
object->set_must_have_output_symtab_entry(r_sym);
|
|
}
|
|
}
|
|
|
|
rr->set_next_reloc_strategy(strategy);
|
|
}
|
|
}
|
|
|
|
// Relocate relocs. Called for a relocatable link, and for --emit-relocs.
|
|
// This is a default definition which should work for most targets.
|
|
|
|
template<int size, bool big_endian, int sh_type>
|
|
void
|
|
relocate_relocs(
|
|
const Relocate_info<size, big_endian>* relinfo,
|
|
const unsigned char* prelocs,
|
|
size_t reloc_count,
|
|
Output_section* output_section,
|
|
typename elfcpp::Elf_types<size>::Elf_Off offset_in_output_section,
|
|
const Relocatable_relocs* rr,
|
|
unsigned char* view,
|
|
typename elfcpp::Elf_types<size>::Elf_Addr view_address,
|
|
section_size_type view_size,
|
|
unsigned char* reloc_view,
|
|
section_size_type reloc_view_size)
|
|
{
|
|
typedef typename elfcpp::Elf_types<size>::Elf_Addr Address;
|
|
typedef typename Reloc_types<sh_type, size, big_endian>::Reloc Reltype;
|
|
typedef typename Reloc_types<sh_type, size, big_endian>::Reloc_write
|
|
Reltype_write;
|
|
const int reloc_size = Reloc_types<sh_type, size, big_endian>::reloc_size;
|
|
const Address invalid_address = static_cast<Address>(0) - 1;
|
|
|
|
Sized_relobj_file<size, big_endian>* const object = relinfo->object;
|
|
const unsigned int local_count = object->local_symbol_count();
|
|
|
|
unsigned char* pwrite = reloc_view;
|
|
|
|
for (size_t i = 0; i < reloc_count; ++i, prelocs += reloc_size)
|
|
{
|
|
Relocatable_relocs::Reloc_strategy strategy = rr->strategy(i);
|
|
if (strategy == Relocatable_relocs::RELOC_DISCARD)
|
|
continue;
|
|
|
|
if (strategy == Relocatable_relocs::RELOC_SPECIAL)
|
|
{
|
|
// Target wants to handle this relocation.
|
|
Sized_target<size, big_endian>* target =
|
|
parameters->sized_target<size, big_endian>();
|
|
target->relocate_special_relocatable(relinfo, sh_type, prelocs,
|
|
i, output_section,
|
|
offset_in_output_section,
|
|
view, view_address,
|
|
view_size, pwrite);
|
|
pwrite += reloc_size;
|
|
continue;
|
|
}
|
|
Reltype reloc(prelocs);
|
|
Reltype_write reloc_write(pwrite);
|
|
|
|
typename elfcpp::Elf_types<size>::Elf_WXword r_info = reloc.get_r_info();
|
|
const unsigned int r_sym = elfcpp::elf_r_sym<size>(r_info);
|
|
const unsigned int r_type = elfcpp::elf_r_type<size>(r_info);
|
|
|
|
// Get the new symbol index.
|
|
|
|
unsigned int new_symndx;
|
|
if (r_sym < local_count)
|
|
{
|
|
switch (strategy)
|
|
{
|
|
case Relocatable_relocs::RELOC_COPY:
|
|
if (r_sym == 0)
|
|
new_symndx = 0;
|
|
else
|
|
{
|
|
new_symndx = object->symtab_index(r_sym);
|
|
gold_assert(new_symndx != -1U);
|
|
}
|
|
break;
|
|
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA:
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0:
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1:
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2:
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4:
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8:
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4_UNALIGNED:
|
|
{
|
|
// We are adjusting a section symbol. We need to find
|
|
// the symbol table index of the section symbol for
|
|
// the output section corresponding to input section
|
|
// in which this symbol is defined.
|
|
gold_assert(r_sym < local_count);
|
|
bool is_ordinary;
|
|
unsigned int shndx =
|
|
object->local_symbol_input_shndx(r_sym, &is_ordinary);
|
|
gold_assert(is_ordinary);
|
|
Output_section* os = object->output_section(shndx);
|
|
gold_assert(os != NULL);
|
|
gold_assert(os->needs_symtab_index());
|
|
new_symndx = os->symtab_index();
|
|
}
|
|
break;
|
|
|
|
default:
|
|
gold_unreachable();
|
|
}
|
|
}
|
|
else
|
|
{
|
|
const Symbol* gsym = object->global_symbol(r_sym);
|
|
gold_assert(gsym != NULL);
|
|
if (gsym->is_forwarder())
|
|
gsym = relinfo->symtab->resolve_forwards(gsym);
|
|
|
|
gold_assert(gsym->has_symtab_index());
|
|
new_symndx = gsym->symtab_index();
|
|
}
|
|
|
|
// Get the new offset--the location in the output section where
|
|
// this relocation should be applied.
|
|
|
|
Address offset = reloc.get_r_offset();
|
|
Address new_offset;
|
|
if (offset_in_output_section != invalid_address)
|
|
new_offset = offset + offset_in_output_section;
|
|
else
|
|
{
|
|
section_offset_type sot_offset =
|
|
convert_types<section_offset_type, Address>(offset);
|
|
section_offset_type new_sot_offset =
|
|
output_section->output_offset(object, relinfo->data_shndx,
|
|
sot_offset);
|
|
gold_assert(new_sot_offset != -1);
|
|
new_offset = new_sot_offset;
|
|
}
|
|
|
|
// In an object file, r_offset is an offset within the section.
|
|
// In an executable or dynamic object, generated by
|
|
// --emit-relocs, r_offset is an absolute address.
|
|
if (!parameters->options().relocatable())
|
|
{
|
|
new_offset += view_address;
|
|
if (offset_in_output_section != invalid_address)
|
|
new_offset -= offset_in_output_section;
|
|
}
|
|
|
|
reloc_write.put_r_offset(new_offset);
|
|
reloc_write.put_r_info(elfcpp::elf_r_info<size>(new_symndx, r_type));
|
|
|
|
// Handle the reloc addend based on the strategy.
|
|
|
|
if (strategy == Relocatable_relocs::RELOC_COPY)
|
|
{
|
|
if (sh_type == elfcpp::SHT_RELA)
|
|
Reloc_types<sh_type, size, big_endian>::
|
|
copy_reloc_addend(&reloc_write,
|
|
&reloc);
|
|
}
|
|
else
|
|
{
|
|
// The relocation uses a section symbol in the input file.
|
|
// We are adjusting it to use a section symbol in the output
|
|
// file. The input section symbol refers to some address in
|
|
// the input section. We need the relocation in the output
|
|
// file to refer to that same address. This adjustment to
|
|
// the addend is the same calculation we use for a simple
|
|
// absolute relocation for the input section symbol.
|
|
|
|
const Symbol_value<size>* psymval = object->local_symbol(r_sym);
|
|
|
|
unsigned char* padd = view + offset;
|
|
switch (strategy)
|
|
{
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_RELA:
|
|
{
|
|
typename elfcpp::Elf_types<size>::Elf_Swxword addend;
|
|
addend = Reloc_types<sh_type, size, big_endian>::
|
|
get_reloc_addend(&reloc);
|
|
addend = psymval->value(object, addend);
|
|
Reloc_types<sh_type, size, big_endian>::
|
|
set_reloc_addend(&reloc_write, addend);
|
|
}
|
|
break;
|
|
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_0:
|
|
break;
|
|
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_1:
|
|
Relocate_functions<size, big_endian>::rel8(padd, object,
|
|
psymval);
|
|
break;
|
|
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_2:
|
|
Relocate_functions<size, big_endian>::rel16(padd, object,
|
|
psymval);
|
|
break;
|
|
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4:
|
|
Relocate_functions<size, big_endian>::rel32(padd, object,
|
|
psymval);
|
|
break;
|
|
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_8:
|
|
Relocate_functions<size, big_endian>::rel64(padd, object,
|
|
psymval);
|
|
break;
|
|
|
|
case Relocatable_relocs::RELOC_ADJUST_FOR_SECTION_4_UNALIGNED:
|
|
Relocate_functions<size, big_endian>::rel32_unaligned(padd,
|
|
object,
|
|
psymval);
|
|
break;
|
|
|
|
default:
|
|
gold_unreachable();
|
|
}
|
|
}
|
|
|
|
pwrite += reloc_size;
|
|
}
|
|
|
|
gold_assert(static_cast<section_size_type>(pwrite - reloc_view)
|
|
== reloc_view_size);
|
|
}
|
|
|
|
} // End namespace gold.
|
|
|
|
#endif // !defined(GOLD_TARGET_RELOC_H)
|