From cc5277b173701364c10204f316db28198f2c683b Mon Sep 17 00:00:00 2001 From: Martin Liska Date: Thu, 4 Jul 2019 16:39:08 +0200 Subject: [PATCH] Support .gnu.lto_.lto section in ELF files (PR 24768). bfd/ChangeLog: 2019-07-22 Martin Liska PR 24768 * archive.c (_bfd_compute_and_write_armap): Come up with report_plugin_err variable. * bfd-in2.h (struct bfd): Add lto_slim_object flag. * elf.c (struct lto_section): New. (_bfd_elf_make_section_from_shdr): Parse content of .gnu_lto_.lto section. * elflink.c: Report error for a missing LTO plugin. * linker.c (_bfd_generic_link_add_one_symbol): Likewise. binutils/ChangeLog: 2019-07-22 Martin Liska PR 24768 * nm.c (filter_symbols): Set report_plugin_err if error is reported. (display_rel_file): Report error for a missing LTO plugin. gold/ChangeLog: 2019-07-22 Martin Liska PR 24768 * layout.h (class Layout): Add is_lto_slim_object and set_lto_slim_object. * object.cc (struct lto_section): Add lto_slim_object_. (big_endian>::do_layout): Parse content of .gnu_lto_.lto section. (big_endian>::do_add_symbols): Report error for a missing LTO plugin. --- bfd/ChangeLog | 12 ++++++++++++ bfd/archive.c | 21 +++++++++++++++++---- bfd/bfd-in2.h | 3 +++ bfd/elf.c | 23 +++++++++++++++++++++++ bfd/elflink.c | 6 ++++++ bfd/linker.c | 24 ++++++++++++++++++------ binutils/ChangeLog | 7 +++++++ binutils/nm.c | 23 ++++++++++++++++++++--- gold/ChangeLog | 11 +++++++++++ gold/layout.h | 10 ++++++++++ gold/object.cc | 31 ++++++++++++++++++++++++++++++- 11 files changed, 157 insertions(+), 14 deletions(-) diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 13649040c08..42583517926 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,15 @@ +2019-07-29 Martin Liska + + PR 24768 + * archive.c (_bfd_compute_and_write_armap): Come up with + report_plugin_err variable. + * bfd-in2.h (struct bfd): Add lto_slim_object flag. + * elf.c (struct lto_section): New. + (_bfd_elf_make_section_from_shdr): Parse content of + .gnu_lto_.lto section. + * elflink.c: Report error for a missing LTO plugin. + * linker.c (_bfd_generic_link_add_one_symbol): Likewise. + 2019-07-28 Alan Modra PR 24857 diff --git a/bfd/archive.c b/bfd/archive.c index 68a92a3e363..0a7da3a0cb9 100644 --- a/bfd/archive.c +++ b/bfd/archive.c @@ -2236,6 +2236,7 @@ _bfd_compute_and_write_armap (bfd *arch, unsigned int elength) long syms_max = 0; bfd_boolean ret; bfd_size_type amt; + static bfd_boolean report_plugin_err = TRUE; /* Dunno if this is the best place for this info... */ if (elength != 0) @@ -2270,6 +2271,14 @@ _bfd_compute_and_write_armap (bfd *arch, unsigned int elength) long symcount; long src_count; + if (current->lto_slim_object && report_plugin_err) + { + report_plugin_err = FALSE; + _bfd_error_handler + (_("%pB: plugin needed to handle lto object"), + current); + } + storage = bfd_get_symtab_upper_bound (current); if (storage < 0) goto error_return; @@ -2322,10 +2331,14 @@ _bfd_compute_and_write_armap (bfd *arch, unsigned int elength) && syms[src_count]->name[1] == '_' && strcmp (syms[src_count]->name + (syms[src_count]->name[2] == '_'), - "__gnu_lto_slim") == 0) - _bfd_error_handler - (_("%pB: plugin needed to handle lto object"), - current); + "__gnu_lto_slim") == 0 + && report_plugin_err) + { + report_plugin_err = FALSE; + _bfd_error_handler + (_("%pB: plugin needed to handle lto object"), + current); + } namelen = strlen (syms[src_count]->name); amt = sizeof (char *); map[orl_count].name = (char **) bfd_alloc (arch, amt); diff --git a/bfd/bfd-in2.h b/bfd/bfd-in2.h index 8374390e60a..7e6dad78d45 100644 --- a/bfd/bfd-in2.h +++ b/bfd/bfd-in2.h @@ -7196,6 +7196,9 @@ struct bfd /* Set if this is a plugin output file. */ unsigned int lto_output : 1; + /* Set if this is a slim LTO object not loaded with a compiler plugin. */ + unsigned int lto_slim_object: 1; + /* Set to dummy BFD created when claimed by a compiler plug-in library. */ bfd *plugin_dummy_bfd; diff --git a/bfd/elf.c b/bfd/elf.c index f47e88b2ac5..6b5d12c0443 100644 --- a/bfd/elf.c +++ b/bfd/elf.c @@ -999,6 +999,18 @@ convert_zdebug_to_debug (bfd *abfd, const char *name) return new_name; } +/* This a copy of lto_section defined in GCC (lto-streamer.h). */ + +struct lto_section +{ + int16_t major_version; + int16_t minor_version; + unsigned char slim_object; + + /* Flags is a private field that is not defined publicly. */ + uint16_t flags; +}; + /* Make a BFD section from an ELF section. We store a pointer to the BFD section in the bfd_section field of the header. */ @@ -1275,6 +1287,17 @@ _bfd_elf_make_section_from_shdr (bfd *abfd, newsect->flags |= SEC_ELF_RENAME; } + /* GCC uses .gnu.lto_.lto. as a LTO bytecode information + section. */ + const char *lto_section_name = ".gnu.lto_.lto."; + if (strncmp (name, lto_section_name, strlen (lto_section_name)) == 0) + { + struct lto_section lsection; + if (bfd_get_section_contents (abfd, newsect, &lsection, 0, + sizeof (struct lto_section))) + abfd->lto_slim_object = lsection.slim_object; + } + return TRUE; } diff --git a/bfd/elflink.c b/bfd/elflink.c index ad146d48fc9..597184582f3 100644 --- a/bfd/elflink.c +++ b/bfd/elflink.c @@ -4401,6 +4401,12 @@ error_free_dyn: goto error_free_vers; } + if (abfd->lto_slim_object) + { + _bfd_error_handler + (_("%pB: plugin needed to handle lto object"), abfd); + } + for (isym = isymbuf, isymend = isymbuf + extsymcount; isym < isymend; isym++, sym_hash++, ever = (ever != NULL ? ever + 1 : NULL)) diff --git a/bfd/linker.c b/bfd/linker.c index 1b71fcf8f0d..edbd0a7df46 100644 --- a/bfd/linker.c +++ b/bfd/linker.c @@ -1421,12 +1421,24 @@ _bfd_generic_link_add_one_symbol (struct bfd_link_info *info, else if (bfd_is_com_section (section)) { row = COMMON_ROW; - if (!bfd_link_relocatable (info) - && name[0] == '_' - && name[1] == '_' - && strcmp (name + (name[2] == '_'), "__gnu_lto_slim") == 0) - _bfd_error_handler - (_("%pB: plugin needed to handle lto object"), abfd); + static bfd_boolean report_plugin_err = TRUE; + if (!bfd_link_relocatable (info) && report_plugin_err) + { + if (abfd->lto_slim_object) + { + report_plugin_err = FALSE; + _bfd_error_handler + (_("%pB: plugin needed to handle lto object"), abfd); + } + else if (name[0] == '_' + && name[1] == '_' + && strcmp (name + (name[2] == '_'), "__gnu_lto_slim") == 0) + { + report_plugin_err = FALSE; + _bfd_error_handler + (_("%pB: plugin needed to handle lto object"), abfd); + } + } } else row = DEF_ROW; diff --git a/binutils/ChangeLog b/binutils/ChangeLog index 91955402828..f3be2641f15 100644 --- a/binutils/ChangeLog +++ b/binutils/ChangeLog @@ -1,3 +1,10 @@ +2019-07-29 Martin Liska + + PR 24768 + * nm.c (filter_symbols): Set report_plugin_err if + error is reported. + (display_rel_file): Report error for a missing LTO plugin. + 2019-07-26 Alan Modra PR 24798 diff --git a/binutils/nm.c b/binutils/nm.c index fd3f73167e0..5d3d6478434 100644 --- a/binutils/nm.c +++ b/binutils/nm.c @@ -438,6 +438,10 @@ print_symdef_entry (bfd *abfd) } } + +/* True when we can report missing plugin error. */ +bfd_boolean report_plugin_err = TRUE; + /* Choose which symbol entries to print; compact them downward to get rid of the rest. Return the number of symbols to be printed. */ @@ -470,9 +474,13 @@ filter_symbols (bfd *abfd, bfd_boolean is_dynamic, void *minisyms, if (sym->name[0] == '_' && sym->name[1] == '_' - && strcmp (sym->name + (sym->name[2] == '_'), "__gnu_lto_slim") == 0) - non_fatal (_("%s: plugin needed to handle lto object"), - bfd_get_filename (abfd)); + && strcmp (sym->name + (sym->name[2] == '_'), "__gnu_lto_slim") == 0 + && report_plugin_err) + { + report_plugin_err = FALSE; + non_fatal (_("%s: plugin needed to handle lto object"), + bfd_get_filename (abfd)); + } if (undefined_only) keep = bfd_is_und_section (sym->section); @@ -1164,6 +1172,15 @@ display_rel_file (bfd *abfd, bfd *archive_bfd) } } + /* lto_slim_object is set to false when a bfd is loaded with a compiler + LTO plugin. */ + if (abfd->lto_slim_object) + { + report_plugin_err = FALSE; + non_fatal (_("%s: plugin needed to handle lto object"), + bfd_get_filename (abfd)); + } + /* Discard the symbols we don't want to print. It's OK to do this in place; we'll free the storage anyway (after printing). */ diff --git a/gold/ChangeLog b/gold/ChangeLog index 67f908885dd..754d0e3eb20 100644 --- a/gold/ChangeLog +++ b/gold/ChangeLog @@ -1,3 +1,14 @@ +2019-07-29 Martin Liska + + PR 24768 + * layout.h (class Layout): Add is_lto_slim_object and + set_lto_slim_object. + * object.cc (struct lto_section): Add lto_slim_object_. + (big_endian>::do_layout): Parse content of + .gnu_lto_.lto section. + (big_endian>::do_add_symbols): Report error for a missing + LTO plugin. + 2019-07-13 Alan Modra * powerpc.cc (xlate_pcrel_opt): New function. diff --git a/gold/layout.h b/gold/layout.h index bfd44e13077..b9b75816e8e 100644 --- a/gold/layout.h +++ b/gold/layout.h @@ -593,6 +593,14 @@ class Layout set_unique_segment_for_sections_specified() { this->unique_segment_for_sections_specified_ = true; } + bool + is_lto_slim_object () const + { return this->lto_slim_object_; } + + void + set_lto_slim_object () + { this->lto_slim_object_ = true; } + // For incremental updates, allocate a block of memory from the // free list. Find a block starting at or after MINOFF. off_t @@ -1480,6 +1488,8 @@ class Layout Incremental_inputs* incremental_inputs_; // Whether we record output section data created in script bool record_output_section_data_from_script_; + // Set if this is a slim LTO object not loaded with a compiler plugin + bool lto_slim_object_; // List of output data that needs to be removed at relaxation clean up. Output_section_data_list script_output_section_data_list_; // Structure to save segment states before entering the relaxation loop. diff --git a/gold/object.cc b/gold/object.cc index 689448f50c8..86c519acf72 100644 --- a/gold/object.cc +++ b/gold/object.cc @@ -1380,6 +1380,18 @@ Sized_relobj_file::layout_gnu_property_section( } } +// This a copy of lto_section defined in GCC (lto-streamer.h) + +struct lto_section +{ + int16_t major_version; + int16_t minor_version; + unsigned char slim_object; + + /* Flags is a private field that is not defined publicly. */ + uint16_t flags; +}; + // 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 @@ -1865,6 +1877,19 @@ Sized_relobj_file::do_layout(Symbol_table* symtab, debug_types_sections.push_back(i); } } + + /* GCC uses .gnu.lto_.lto. as a LTO bytecode information + section. */ + const char *lto_section_name = ".gnu.lto_.lto."; + if (strncmp (name, lto_section_name, strlen (lto_section_name)) == 0) + { + section_size_type contents_len; + const unsigned char* pcontents = this->section_contents(i, &contents_len, false); + struct lto_section lsection = *(const lto_section*)pcontents; + if (lsection.slim_object) + gold_info(_("%s: plugin needed to handle lto object"), + this->name().c_str()); + } } if (!is_pass_two) @@ -2083,7 +2108,7 @@ template void Sized_relobj_file::do_add_symbols(Symbol_table* symtab, Read_symbols_data* sd, - Layout*) + Layout* layout) { if (sd->symbols == NULL) { @@ -2102,6 +2127,10 @@ Sized_relobj_file::do_add_symbols(Symbol_table* symtab, this->symbols_.resize(symcount); + if (layout->is_lto_slim_object ()) + gold_info(_("%s: plugin needed to handle lto object"), + this->name().c_str()); + const char* sym_names = reinterpret_cast(sd->symbol_names->data()); symtab->add_from_relobj(this, -- 2.30.2