From 3a9e6ee42acf1e3d00e4391ab1b1a56bb0b32ad2 Mon Sep 17 00:00:00 2001 From: Mark Wielaard Date: Tue, 6 Oct 2020 17:41:19 +0200 Subject: [PATCH] debug: Make sure to output .file 0 when generating DWARF5. When gas outputs DWARF5 .debug_line[_str] then we have to tell it the comp_dir and main file name for the zero entry line table. Otherwise gas has to guess at the CU compilation directory and file. Before a gcc -gdwarf-5 ../src/hello.c line table looked like: Directory table: 0 ../src (24) 1 ../src (24) 2 /usr/include (31) File name table: 0 hello.c (16), 0 1 hello.c (16), 1 2 stdio.h (44), 2 With this patch it looks like: Directory table: 0 /tmp/obj (0) 1 ../src (24) 2 /usr/include (31) File name table: 0 ../src/hello.c (9), 0 1 hello.c (16), 1 2 stdio.h (44), 2 gcc/ChangeLog: * dwarf2out.c (dwarf2out_finish): Emit .file 0 entry when generating DWARF5 .debug_line table through gas. --- gcc/dwarf2out.c | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c index 30367443ad6..ba93a6c3d81 100644 --- a/gcc/dwarf2out.c +++ b/gcc/dwarf2out.c @@ -31768,6 +31768,27 @@ dwarf2out_finish (const char *filename) ASM_OUTPUT_LABEL (asm_out_file, debug_line_section_label); if (! output_asm_line_debug_info ()) output_line_info (false); + else if (asm_outputs_debug_line_str ()) + { + /* When gas outputs DWARF5 .debug_line[_str] then we have to + tell it the comp_dir and main file name for the zero entry + line table. */ + const char *comp_dir, *filename0; + + comp_dir = comp_dir_string (); + if (comp_dir == NULL) + comp_dir = ""; + + filename0 = get_AT_string (comp_unit_die (), DW_AT_name); + if (filename0 == NULL) + filename0 = ""; + + fprintf (asm_out_file, "\t.file 0 "); + output_quoted_string (asm_out_file, remap_debug_filename (comp_dir)); + fputc (' ', asm_out_file); + output_quoted_string (asm_out_file, remap_debug_filename (filename0)); + fputc ('\n', asm_out_file); + } if (dwarf_split_debug_info && info_section_emitted) { -- 2.30.2