[Bug target/114679] New: .file directive missing on MIPS ports when debug symbols are enabled.

[Bug target/114679] New: .file directive missing on MIPS ports when debug symbols are enabled.

[jan.smets at nokia dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114679

            Bug ID: 114679
           Summary: .file directive missing on MIPS ports when debug
                    symbols are enabled.
           Product: gcc
           Version: 12.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jan.smets at nokia dot com
  Target Milestone: ---

I noticed that the .file directive prints differently on targets (mips vs x86)
when (dwarf) debug symbols are enabled.

output_file_directive() strips the directories and calls
output_source_filename()
For most targets (that do not define a TARGET_ASM_OUTPUT_SOURCE_FILENAME) that
is default_asm_output_source_filename(), which prints the directory stripped
filename. 
(.file X.c , without a number)

For MIPS, TARGET_ASM_OUTPUT_SOURCE_FILENAME is mips_output_filename().
mips_output_filename() defers the writing of .file to dwarf2out when debug
symbols are enabled, otherwise it prints the directory stripped file as ".file
N X.c"

Essentially we're missing the ".file" on MIPS when debug symbols are enabled.


gcc version 12.2.0 (Debian 12.2.0-14)


mkdir -p /tmp/a/b/c
echo 'void test(void){}' > /tmp/a/b/c/test.c
$GCC \
 -o /tmp/out -S \
  -g0 (or -g)  \
 -ffile-prefix-map=/tmp/a/= \
  -c /tmp/a/b/c/test.c \
head -n1 /tmp/out



X86 vs MIPS , -g0 
<       .file   "test.c"
---
>       .file   1 "test.c"

X86 vs MIPS, -g

<       .file   "test.c"
---
>       <MISSING>

Can we have MIPS behave similar to other targets? 

Ideally I would like .file to have "b/c/test.c" instead of just "test.c", but
that's perhaps a different discussion.

diff --git a/gcc/config/mips/mips.cc b/gcc/config/mips/mips.cc
index ce764a5cb35..210b87a85d8 100644
--- a/gcc/config/mips/mips.cc
+++ b/gcc/config/mips/mips.cc
@@ -9756,11 +9756,7 @@ mips_output_external (FILE *file, tree decl, const char
*name)
 static void
 mips_output_filename (FILE *stream, const char *name)
 {
-  /* If we are emitting DWARF-2, let dwarf2out handle the ".file"
-     directives.  */
-  if (dwarf_debuginfo_p ())
-    return;
-  else if (mips_output_filename_first_time)
+  if (mips_output_filename_first_time)
     {
       mips_output_filename_first_time = 0;
       num_source_filenames += 1;