From: Tom de Vries Date: Wed, 20 Sep 2023 14:05:55 +0000 (+0200) Subject: [gdb/symtab] Error out for .debug_types section in dwz file X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=973db6fae304c2bcafff5f169610f663adc9e817;p=binutils-gdb.git [gdb/symtab] Error out for .debug_types section in dwz file There are two methods to factor out type information in a dwarf4 executable: - use -fdebug-info-types to generate type units in a .debug_types section, and - use dwz to create partial units. The dwz method has an extra benefit: it also allows to factor out information between executables into a newly created .dwz file, pointed to by a .gnu_debugaltlink section. There is nothing prohibiting a .gnu_debugaltlink file to contain a .debug_types section. It's just not generated by dwz or any other tool atm, and consequently gdb has no support for it. Enhancement PR symtab/30838 is open about the lack of support. Make the current situation explicit by emitting a dwarf error: ... (gdb) file struct-with-sig-2^M Reading symbols from struct-with-sig-2...^M Dwarf Error: .debug_types section not supported in dwz file^M ... and add an assert in write_gdbindex: ... + /* See enhancement PR symtab/30838. */ + gdb_assert (!(per_cu->is_dwz && per_cu->is_debug_types)); ... to clarify why we can use: ... data_buf &cu_list = (per_cu->is_debug_types ? types_cu_list : per_cu->is_dwz ? dwz_cu_list : objfile_cu_list); ... The test-case is a modified copy from gdb.dwarf2/struct-with-sig.exp, so it keeps the copyright years range. Tested on x86_64-linux. Tested-By: Guinevere Larsen Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30838 --- diff --git a/gdb/dwarf2/dwz.c b/gdb/dwarf2/dwz.c index 447c942da6a..bd2bcb91d83 100644 --- a/gdb/dwarf2/dwz.c +++ b/gdb/dwarf2/dwz.c @@ -91,6 +91,11 @@ locate_dwz_sections (bfd *abfd, asection *sectp, dwz_file *dwz_file) dwz_file->debug_names.s.section = sectp; dwz_file->debug_names.size = bfd_section_size (sectp); } + else if (dwarf2_elf_names.types.matches (sectp->name)) + { + dwz_file->types.s.section = sectp; + dwz_file->types.size = bfd_section_size (sectp); + } } /* Attempt to find a .dwz file (whose full path is represented by diff --git a/gdb/dwarf2/dwz.h b/gdb/dwarf2/dwz.h index 232b4dbce01..5f61b5e1216 100644 --- a/gdb/dwarf2/dwz.h +++ b/gdb/dwarf2/dwz.h @@ -48,6 +48,7 @@ struct dwz_file struct dwarf2_section_info macro {}; struct dwarf2_section_info gdb_index {}; struct dwarf2_section_info debug_names {}; + struct dwarf2_section_info types {}; /* The dwz's BFD. */ gdb_bfd_ref_ptr dwz_bfd; diff --git a/gdb/dwarf2/index-write.c b/gdb/dwarf2/index-write.c index 1b5d4c10b0c..3acff266ab3 100644 --- a/gdb/dwarf2/index-write.c +++ b/gdb/dwarf2/index-write.c @@ -1221,6 +1221,9 @@ write_gdbindex (dwarf2_per_bfd *per_bfd, cooked_index *table, const auto insertpair = cu_index_htab.emplace (per_cu, counter); gdb_assert (insertpair.second); + /* See enhancement PR symtab/30838. */ + gdb_assert (!(per_cu->is_dwz && per_cu->is_debug_types)); + /* The all_units list contains CUs read from the objfile as well as from the eventual dwz file. We need to place the entry in the corresponding index. */ diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c index 8757bee51fe..7fc017eae9e 100644 --- a/gdb/dwarf2/read.c +++ b/gdb/dwarf2/read.c @@ -5314,6 +5314,12 @@ create_all_units (dwarf2_per_objfile *per_objfile) dwz->line.read (objfile); read_comp_units_from_section (per_objfile, &dwz->info, &dwz->abbrev, 1, types_htab, rcuh_kind::COMPILE); + + if (!dwz->types.empty ()) + { + /* See enhancement PR symtab/30838. */ + error (_("Dwarf Error: .debug_types section not supported in dwz file")); + } } per_objfile->per_bfd->signatured_types = std::move (types_htab); diff --git a/gdb/testsuite/gdb.dwarf2/struct-with-sig-2.exp b/gdb/testsuite/gdb.dwarf2/struct-with-sig-2.exp new file mode 100644 index 00000000000..f6877fc6a17 --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/struct-with-sig-2.exp @@ -0,0 +1,128 @@ +# Copyright 2020-2023 Free Software Foundation, Inc. + +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 3 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program. If not, see . + +# Variant of struct-with-sig.exp where TUs are in .gnu_debugaltlink file. + +load_lib dwarf.exp + +# This test can only be run on targets which support DWARF-2 and use gas. +require dwarf2_support + +standard_testfile main-foo.c .S .S + +set build_id [string repeat ff 20] + +# Make some DWARF for the dwz file. +set asm_file [standard_output_file $srcfile2] +Dwarf::assemble $asm_file { + build_id $::build_id + + tu {} 0x0000000000000001 the_type_i { + type_unit {} { + declare_labels int_type + + the_type_i: structure_type { + {name s} + {byte_size 4 sdata} + } { + member { + {name i} + {type :$int_type} + } + } + int_type: base_type { + {name int} + {encoding @DW_ATE_signed} + {byte_size 4 sdata} + } + } + } + + tu {} 0x0000000000000002 the_type_j { + type_unit {} { + declare_labels int_type + + the_type_j: structure_type { + {name s} + {byte_size 4 sdata} + } { + member { + {name j} + {type :$int_type} + } + } + int_type: base_type { + {name int} + {encoding @DW_ATE_signed} + {byte_size 4 sdata} + } + } + } +} + +# We're using an object instead of executable here to keep cc-with-tweaks.sh +# from modifying it. It also means we can set the build-id, rather than +# having to extract it. +if { [gdb_compile $asm_file $binfile.dwz object {nodebug}] != "" } { + return -1 +} + +set host_dwz_file [gdb_remote_download host $binfile.dwz] + +# Make some DWARF for the executable. +set asm_file [standard_output_file $srcfile3] +Dwarf::assemble $asm_file { + gnu_debugaltlink $::host_dwz_file $::build_id + + cu {} { + compile_unit { + {DW_AT_language @DW_LANG_C} + {DW_AT_name main.c} + } { + structure_type { + {name s} + {signature 0x0000000000000001 ref_sig8} + {declaration 1 flag} + } + DW_TAG_subprogram { + {MACRO_AT_func {main}} + } + } + } + + cu {} { + compile_unit { + {DW_AT_language @DW_LANG_C} + {DW_AT_name foo.c} + } { + structure_type { + {name s} + {signature 0x0000000000000002 ref_sig8} + {declaration 1 flag} + } + DW_TAG_subprogram { + {MACRO_AT_func {foo}} + } + } + } +} + +if { [prepare_for_testing "failed to prepare" ${testfile} \ + [list $srcfile $asm_file] {nodebug}] } { + return -1 +} + +set re "Dwarf Error: .debug_types section not supported in dwz file" +gdb_assert { [regexp $re $gdb_file_cmd_msg] } "Dwarf Error message"