* object.cc (Sized_relobj::do_layout): Use constant invalid_address
instead of -1U.
(Sized_relobj::do_finalize_local_symbols): Likewise.
(Sized_relobj::map_to_kept_section): Likewise.
* object.h (Sized_relobj::invalid_address): New constant.
(Sized_relobj::do_output_section_offset): Check for invalid_address
and return -1ULL.
* output.cc (Output_reloc::local_section_offset): Use constant
invalid_address instead of -1U.
(Output_reloc::get_address): Likewise.
(Output_section::output_address): Change -1U to -1ULL.
* output.h (Output_reloc::invalid_address): New constant.
* reloc.cc (Sized_relobj::write_sections): Use constant
invalid_address instead of -1U.
(Sized_relobj::relocate_sections): Likewise.
* symtab.cc (Symbol_table::sized_finalize_symbol): Handle symbol
values for merge sections.
* target-reloc.h (relocate_for_relocatable): Use constant
invalid_address instead of -1U.
include/:
* plugin-api.h: New file.
gold/:
* configure.ac (plugins): Add --enable-plugins option.
* configure: Regenerate.
* config.in: Regenerate.
* Makefile.am (LIBDL): New variable.
(CCFILES): Add plugin.cc.
(HFILES): Add plugin.h.
(ldadd_var): Add LIBDL.
* Makefile.in: Regenerate.
* archive.cc: Include "plugin.h".
(Archive::setup): Don't preread archive symbols when using a plugin.
(Archive::get_file_and_offset): Add memsize parameter. Change callers.
(Archive::get_elf_object_for_member): Call plugin hooks for claiming
files.
(Archive::include_member): Add symbols from plugin objects.
* archive.h (Archive::get_file_and_offset): Add memsize parameter.
* descriptors.cc (Descriptors::open): Check for file descriptors
abandoned by plugins.
(Descriptors::claim_for_plugin): New function.
* descriptors.h (Descriptors::claim_for_plugin): New function.
(Open_descriptor::is_claimed): New field.
(claim_descriptor_for_plugin): New function.
* fileread.cc (File_read::claim_for_plugin): New function.
* fileread.h (File_read::claim_for_plugin): New function.
(File_read::descriptor): New function.
* gold.cc: Include "plugin.h".
(queue_initial_tasks): Add task to call plugin hooks for generating
new object files.
* main.cc: Include "plugin.h".
(main): Load plugin libraries.
* object.h (Pluginobj): Declare.
(Object::pluginobj): New function.
(Object::do_pluginobj): New function.
(Object::set_target): New function.
* options.cc: Include "plugin.h".
(General_options::parse_plugin): New function.
(General_options::General_options): Initialize plugins_ field.
(General_options::add_plugin): New function.
* options.h (Plugin_manager): Declare.
(General_options): Add --plugin option.
(General_options::has_plugins): New function.
(General_options::plugins): New function.
(General_options::add_plugin): New function.
(General_options::plugins_): New field.
* plugin.cc: New file.
* plugin.h: New file.
* readsyms.cc: Include "plugin.h".
(Read_symbols::do_read_symbols): Check for archive before checking
for ELF file. Call plugin hooks to claim files.
* resolve.cc (Symbol_table::resolve): Record when symbol is referenced
from a real object file; force override when processing replacement
files.
* symtab.cc (Symbol::init_fields): Initialize in_real_elf_ field.
(Symbol::init_base_object): Likewise.
(Symbol::init_base_output_data): Likewise.
(Symbol::init_base_output_segment): Likewise.
(Symbol::init_base_constant): Likewise.
(Symbol::init_base_undefined): Likewise.
(Symbol::output_section): Assert that object is not a plugin.
(Symbol_table::add_from_pluginobj): New function.
(Symbol_table::sized_finalize_symbol): Treat symbols from plugins as
undefined.
(Symbol_table::sized_write_globals): Likewise.
(Symbol_table::add_from_pluginobj): Instantiate template.
* symtab.h (Sized_pluginobj): Declare.
(Symbol::in_real_elf): New function.
(Symbol::set_in_real_elf): New function.
(Symbol::in_real_elf_): New field.
(Symbol_table::add_from_pluginobj): New function.
* testsuite/Makefile.am (AM_CFLAGS): New variable.
(LIBDL): New variable.
(LDADD): Add LIBDL.
(check_PROGRAMS): Add plugin_test_1 and plugin_test_2.
(check_SCRIPTS): Add plugin_test_1.sh and plugin_test_2.sh.
(check_DATA): Add plugin_test_1.err and plugin_test_2.err.
(MOSTLYCLEANFILES): Likewise.
* testsuite/Makefile.in: Regenerate.
* testsuite/plugin_test.c: New file.
* testsuite/plugin_test_1.sh: New file.
* testsuite/plugin_test_2.sh: New file.
* descriptors.cc: New file.
* descriptors.h: New file.
* gold-threads.h (class Hold_optional_lock): New class.
* fileread.cc: Include "descriptors.h".
(File_read::~File_read): Release descriptor rather than closing
it.
(File_read::open) [file]: Call open_descriptor rather than open.
Set is_descriptor_opened_.
(File_read::open) [memory]: Assert that descriptor is not open.
(File_read::reopen_descriptor): New function.
(File_read::release): Release descriptor.
(File_read::do_read): Make non-const. Reopen descriptor.
(File_read::read): Make non-const.
(File_read::make_view): Reopen descriptor.
(File_read::do_readv): Likewise.
* fileread.h (class File_read): Add is_descriptor_opened_ field.
Update declarations.
* layout.cc: Include "descriptors.h".
(Layout::create_build_id): Use open_descriptor rather than open.
* output.cc: Include "descriptors.h".
(Output_file::open): Use open_descriptor rather than open.
* archive.cc (Archive::const_iterator): Change Archive to be
non-const.
(Archive::begin, Archive::end): Make non-const.
(Archive::count_members): Likewise.
* archive.h (class Archive): Update declarations.
* object.h (Object::read): Make non-const.
* Makefile.am (CCFILES): Add descriptors.cc.
(HFILES): Add descriptors.h.
* Makefile.in: Rebuild.
* object.h (class Relobj): Change map_to_output_ to
output_sections_, and just keep a section pointer. Change all
uses. Move comdat group support to Sized_relobj.
(Relobj::is_section_specially_mapped): Remove.
(Relobj::output_section): Remove poff parameter. Change all
callers.
(Relobj::output_section_offset): New function.
(Relobj::set_section_offset): Rewrite.
(Relobj::map_to_output): Remove.
(Relobj::output_sections): New function.
(Relobj::do_output_section_offset): New pure virtual function.
(Relobj::do_set_section_offset): Likewise.
(class Sized_relobj): Add section_offsets_ field. Add comdat
group support from Relobj. Update declarations.
(Sized_relobj::get_output_section_offset): New function.
(Sized_relobj::do_output_section_offset): New function.
(Sized_relobj::do_set_section_offset): New function.
* object.cc (Relobj::output_section_address): Remove.
(Sized_relobj::Sized_relobj): Initialize new fields.
(Sized_relobj::include_section_group): Cast find_kept_object to
Sized_relobj.
(Sized_relobj::include_linkonce_section): Likewise.
(Sized_relobj::do_layout): Use separate arrays for output section
and output offset.
(Sized_relobj::do_count_local_symbols): Change map_to_output to
output_sections.
(Sized_relobj::do_finalize_local_symbols): Change map_to_output to
output_sections and section_offsets.
(Sized_relobj::write_local_symbols): Likewise.
(map_to_kept_section): Compute output address directly.
* reloc.cc (Sized_relobj::do_read_relocs): Change map_to_output to
output_sections and section_offsets.
(Sized_relobj::write_sections): Likewise.
(Sized_relobj::relocate_sections): Likewise.
* symtab.cc (sized_finalize_symbol): Use output_section_offset.
* output.h (class Output_reloc): Update declarations. Change
u2_.relobj to Sized_relobj*.
(class Output_data_reloc): Change add functions to use
Sized_relobj*.
* output.cc (Output_reloc::Output_reloc): Change relobj to
Sized_relobj*.
(Output_reloc::local_section_offset): Change return type to
Elf_Addr. Use get_output_section_offset.
(Output_reloc::get_address): Likewise.
(Output_section::is_input_address_mapped): Don't call
is_section_specially_mapped.
(Output_section::output_offset): Likewise.
(Output_section::output_address): Likewise.
(Output_section::starting_output_address): Likewise.
* copy-relocs.cc (Copy_relocs::copy_reloc): Change object
parameter to Sized_relobj*.
(Copy_relocs::need_copy_reloc): Likewise.
(Copy_relocs::save): Likewise.
* copy-relocs.h (class Copy_relocs): Update declarations.
(class Copy_relocs::Copy_reloc_entry): Change constructor to use
Sized_relobj*. Change relobj_ field to Sized_relobj*.
* target-reloc.h (relocate_for_relocatable): Change
offset_in_output_section type to Elf_Addr. Change code that uses
it as well.
* layout.cc (Layout::layout): Always set *off.
* mapfile.cc (Mapfile::print_input_section): Use
output_section_offset.
* i386.cc (Target_i386::copy_reloc): Change object parameter to
Sized_relobj*.
* powerpc.cc (Target_powerpc::copy_reloc): Likewise.
* sparc.cc (Target_sparc::copy_reloc): Likewise.
* x86_64.cc (Target_x86_64::copy_reloc): Likewise.
info section.
(Layout::add_comdat): Add new parameters. Change type
of signature parameter. Add object and shndx to signatures table.
(Layout::find_kept_object): New function.
* layout.h: Include <cstring>.
(Layout::is_debug_info_section): New function.
(Layout::add_comdat): Add new parameters.
(Layout::find_kept_object): New function.
(Layout::Kept_section): New struct.
(Layout::Signatures): Change type of map range.
* object.cc (Relobj::output_section_address): New function.
(Sized_relobj::include_section_group): Add new parameters. Change
calls to Layout::add_comdat. Change to build table of kept comdat
groups and table mapping discarded sections to kept sections.
(Sized_relobj::include_linkonce_section): Likewise. Add new parameter.
(Sized_relobj::do_layout): Change calls to include_section_group and
include_linkonce_section.
(Sized_relobj::do_finalize_local_symbols): Do not set local symbol
value to zero when section is discarded.
(Sized_relobj::map_to_kept_section): New function.
* object.h (Relobj::output_section_address): New function.
(Relobj::Comdat_group): New type.
(Relobj::find_comdat_group): New function.
(Relobj::Comdat_group_table): New type.
(Relobj::Kept_comdat_section): New type.
(Relobj::Kept_comdat_section_table): New type.
(Relobj::add_comdat_group): New function.
(Relobj::set_kept_comdat_section): New function.
(Relobj::get_kept_comdat_section): New function.
(Relobj::comdat_groups_): New field.
(Relobj::kept_comdat_sections_): New field.
(Symbol_value::input_value): Update comment.
(Sized_relobj::map_to_kept_section) New function.
(Sized_relobj::include_linkonce_section): Add new parameter.
* target-reloc.h (Comdat_behavior): New type.
(get_comdat_behavior): New function.
(relocate_section): Add code to map a discarded section to the
corresponding kept section when applying a relocation.
parameters. Update for new key type to views_. Change all
callers.
(File_read::read): Adjust for byteshift in returned view.
(File_read::add_view): New function, broken out of
find_and_make_view.
(File_read::make_view): New function, broken out of
find_and_make_view.
(File_read::find_or_make_view): Add offset and aligned
parameters. Rewrite accordingly. Change all callers.
(File_read::get_view): Add offset and aligned parameters. Adjust
for byteshift in return value.
(File_read::get_lasting_view): Likewise.
* fileread.h (class File_read): Update declarations.
(class File_read::View): Add byteshift_ field. Add byteshift to
constructor. Add byteshift method.
* archive.h (Archive::clear_uncached_views): New function.
(Archive::get_view): Add aligned parameter. Change all callers.
* object.h (Object::get_view): Add aligned parameter. Change all
callers.
(Object::get_lasting_view): Likewise.
* fileread.cc (File_read::release): Don't call clear_views if
there are multiple objects.
* fileread.h (File_read::clear_uncached_views): New function.
* archive.cc (Add_archive_symbols::run): Call clear_uncached_views
on the archive.