Consider a hello world, compiled with -gsplit-dwarf and dwarf version 4, and -g3: ... $ gcc -gdwarf-4 -gsplit-dwarf /data/vries/hello.c -g3 -save-temps -dA ...
In section .debug_macro.dwo, we have: ... .Ldebug_macro0: .value 0x4 # DWARF macro version number .byte 0x2 # Flags: 32-bit, lineptr present .long .Lskeleton_debug_line0 .byte 0x3 # Start new file .uleb128 0 # Included from line number 0 .uleb128 0x1 # file /data/vries/hello.c .byte 0x5 # Define macro strp .uleb128 0 # At line number 0 .uleb128 0x1d0 # The macro: "__STDC__ 1" ... Given that we use a DW_MACRO_define_strp, we'd expect 0x1d0 to be an offset into a .debug_str.dwo section. But in fact, 0x1d0 is an index into the string offset table in .debug_str_offsets.dwo: ... .long 0x34f0 # indexed string 0x1d0: __STDC__ 1 ... Add asserts that catch this inconsistency, and fix this by using DW_MACRO_define_strx instead. Tested on x86_64. PR debug/115066 --- gcc/dwarf2out.cc | 20 ++++++++++++++------ gcc/testsuite/gcc.dg/pr115066.c | 8 ++++++++ 2 files changed, 22 insertions(+), 6 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/pr115066.c diff --git a/gcc/dwarf2out.cc b/gcc/dwarf2out.cc index eedb13bb069..70b7f5f42cd 100644 --- a/gcc/dwarf2out.cc +++ b/gcc/dwarf2out.cc @@ -29045,7 +29045,7 @@ output_macinfo_op (macinfo_entry *ref) && !DWARF2_INDIRECT_STRING_SUPPORT_MISSING_ON_TARGET && (debug_str_section->common.flags & SECTION_MERGE) != 0) { - if (dwarf_split_debug_info && dwarf_version >= 5) + if (dwarf_split_debug_info) ref->code = ref->code == DW_MACINFO_define ? DW_MACRO_define_strx : DW_MACRO_undef_strx; else @@ -29097,12 +29097,20 @@ output_macinfo_op (macinfo_entry *ref) HOST_WIDE_INT_PRINT_UNSIGNED, ref->lineno); if (node->form == DW_FORM_strp) - dw2_asm_output_offset (dwarf_offset_size, node->label, - debug_str_section, "The macro: \"%s\"", - ref->info); + { + gcc_assert (ref->code == DW_MACRO_define_strp + || ref->code == DW_MACRO_undef_strp); + dw2_asm_output_offset (dwarf_offset_size, node->label, + debug_str_section, "The macro: \"%s\"", + ref->info); + } else - dw2_asm_output_data_uleb128 (node->index, "The macro: \"%s\"", - ref->info); + { + gcc_assert (ref->code == DW_MACRO_define_strx + || ref->code == DW_MACRO_undef_strx); + dw2_asm_output_data_uleb128 (node->index, "The macro: \"%s\"", + ref->info); + } break; case DW_MACRO_import: dw2_asm_output_data (1, ref->code, "Import"); diff --git a/gcc/testsuite/gcc.dg/pr115066.c b/gcc/testsuite/gcc.dg/pr115066.c new file mode 100644 index 00000000000..645757df209 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr115066.c @@ -0,0 +1,8 @@ +/* { dg-do compile } */ +/* { dg-skip-if "split DWARF unsupported" { hppa*-*-hpux* powerpc*-ibm-aix* *-*-darwin* } } */ +/* { dg-options "-gsplit-dwarf -g3 -dA -gdwarf-4" } */ +/* { dg-final { scan-assembler-times {\.section\t"?\.debug_macro} 1 } } */ +/* { dg-final { scan-assembler-not {\.byte\t0x5\t# Define macro strp} } } */ +/* { dg-final { scan-assembler {\.byte\t0xb\t# Define macro strx} } } */ + +#define foo 1 base-commit: 2d0eeb529d400e61197a09c56011be976dd81ef0 -- 2.35.3