From 263ad5cc818ef8f7700c82f2aecd2a929dbd3be5 Mon Sep 17 00:00:00 2001 From: Tom de Vries Date: Fri, 22 Jul 2022 23:50:48 +0200 Subject: [PATCH] [gdb/symtab] Fix duplicate CUs in all_comp_units When running test-case gdb.cp/cpexprs-debug-types.exp with target board cc-with-debug-names on a system with gcc 12.1.1 (defaulting to dwarf 5), I run into: ... (gdb) file cpexprs-debug-types^M Reading symbols from cpexprs-debug-types...^M warning: Section .debug_aranges in cpexprs-debug-types has duplicate \ debug_info_offset 0x0, ignoring .debug_aranges.^M gdb/dwarf2/read.h:309: internal-error: set_length: \ Assertion `m_length == length' failed.^M ... The exec contains a .debug_names section, which gdb rejects due to .debug_names containing a list of TUs, while the exec doesn't contain a .debug_types section (which is what you'd expect for dwarf 4). Gdb then falls back onto the cooked index, which calls create_all_comp_units to create all_comp_units. However, the failed index reading left some elements in all_comp_units, so we end up with duplicates in all_comp_units, which causes the misleading complaint and the assert. Fix this by: - asserting at the start of create_all_comp_units that all_comp_units is empty, as we do in create_cus_from_index and create_cus_from_debug_names, and - cleaning up all_comp_units when failing in dwarf2_read_debug_names. Add a similar cleanup in dwarf2_read_gdb_index. Tested on x86_64-linux. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29381 --- gdb/dwarf2/read.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c index 42230607fe0..f7e55af3e86 100644 --- a/gdb/dwarf2/read.c +++ b/gdb/dwarf2/read.c @@ -2696,7 +2696,10 @@ dwarf2_read_gdb_index /* We can only handle a single .debug_types when we have an index. */ if (per_bfd->types.size () != 1) - return 0; + { + per_bfd->all_comp_units.clear (); + return 0; + } dwarf2_section_info *section = &per_bfd->types[0]; @@ -4701,7 +4704,10 @@ dwarf2_read_debug_names (dwarf2_per_objfile *per_objfile) /* We can only handle a single .debug_types when we have an index. */ if (per_bfd->types.size () != 1) - return false; + { + per_bfd->all_comp_units.clear (); + return false; + } dwarf2_section_info *section = &per_bfd->types[0]; @@ -7214,6 +7220,7 @@ static void create_all_comp_units (dwarf2_per_objfile *per_objfile) { htab_up types_htab; + gdb_assert (per_objfile->per_bfd->all_comp_units.empty ()); read_comp_units_from_section (per_objfile, &per_objfile->per_bfd->info, &per_objfile->per_bfd->abbrev, 0, -- 2.30.2