RE: [PATCH] test: basename filenames in dwarf2 frame checks

Filipovic, Bratislav
2026-04-02T13:02:17Z

[AMD Official Use Only - AMD Internal Distribution Only]

Hello Andrew,

I still don't have write-after-approval yet. Can you get it pushed?

Regards Bratislav

-----Original Message-----
From: Andrew Burgess <aburgess@redhat.com>
Sent: Thursday, April 2, 2026 2:53 PM
To: Filipovic, Bratislav <Bratislav.Filipovic@amd.com>
Cc: Filipovic, Bratislav <Bratislav.Filipovic@amd.com>; gdb-patches@sourceware.org; simon.marchi@efficios.com
Subject: Re: [PATCH] test: basename filenames in dwarf2 frame checks

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Bratislav Filipovic <bfilipov@amd.com> writes:

> Some gdb.dwarf2 tests match the output of commands like frame and
> expect to see locations printed as fission-base.c:LINE (no directory
> prefix). When the test programs are built with clang as
> CC_FOR_TARGET, GDB can print an absolute source path instead, causing FAILs.
>
> For example, with clang:
>
> (gdb) PASS: gdb.dwarf2/fission-base.exp: ptype func
> (gdb) frame
> #0 main () at /path/to/gdb/testsuite/fission-base.c:27
> 27 return func (-1);
> (gdb) FAIL: gdb.dwarf2/fission-base.exp: frame in main
>
> With gcc:
>
> (gdb) PASS: gdb.dwarf2/fission-base.exp: ptype func
> (gdb) frame
> #0 main () at fission-base.c:27
> 27 return func (-1);
> (gdb) PASS: gdb.dwarf2/fission-base.exp: frame in main
>
> The difference comes from the DWARF line table contents. With clang,
> the .debug_line directory table can contain an absolute directory that
> the file table entries reference:
>
> The Directory Table:
> 0 /path/to/gdb/testsuite
>
> The File Name Table:
> 0 Dir=0 Name=fission-base.c
> 1 Dir=0 Name=fission-base.c
>
> Whereas with gcc the directory table is empty and only the bare
> filename is present:
>
> The Directory Table is empty.
>
> The File Name Table:
> 1 Name=fission-base.c
>
> This difference reflects toolchain/assembler behavior in how
> .file/.loc are translated into .debug_line and is orthogonal to what
> these tests aim to validate.
>
> Force set filename-display basename in the affected tests so the
> output is stable across toolchains.
>
> Test: gdb.dwarf2/fission-base.exp (CC_FOR_TARGET=clang, gcc)
> Test: gdb.dwarf2/dw2-undefined-ret-addr.exp (CC_FOR_TARGET=clang, gcc)
> ---
>
> Thanks for the review Andrew. Fixed the comments.

Looks good. Feel free to push this patch.

Approved-By: Andrew Burgess <aburgess@redhat.com>

Thanks,
Andrew

>
> Regards Bratislav
>
>
> gdb/testsuite/gdb.dwarf2/dw2-undefined-ret-addr.exp | 5 +++++
> gdb/testsuite/gdb.dwarf2/fission-base.exp | 5 +++++
> 2 files changed, 10 insertions(+)
>
> diff --git a/gdb/testsuite/gdb.dwarf2/dw2-undefined-ret-addr.exp
> b/gdb/testsuite/gdb.dwarf2/dw2-undefined-ret-addr.exp
> index 32ddaf4a..88765d4f 100644
> --- a/gdb/testsuite/gdb.dwarf2/dw2-undefined-ret-addr.exp
> +++ b/gdb/testsuite/gdb.dwarf2/dw2-undefined-ret-addr.exp
> @@ -30,6 +30,11 @@ if {![runto "stop_frame"]} {
> return -1
> }
>
> +# If test is compiled with clang, GDB would display absolute path.
> +# This command keeps output consistent across toolchains.
> +
> +gdb_test_no_output "set filename-display basename"
> +
> # stop_frame should be the outermost frame.
>
> # Check that backtrace shows only frame #0.
> diff --git a/gdb/testsuite/gdb.dwarf2/fission-base.exp
> b/gdb/testsuite/gdb.dwarf2/fission-base.exp
> index 035fe731..d1abf6c9 100644
> --- a/gdb/testsuite/gdb.dwarf2/fission-base.exp
> +++ b/gdb/testsuite/gdb.dwarf2/fission-base.exp
> @@ -46,6 +46,11 @@ if {![runto_main]} { gdb_test "ptype main" "type =
> int \\(\\)"
> gdb_test "ptype func" "type = int \\(int\\)"
>
> +# If test is compiled with clang, GDB would display absolute path.
> +# This command keeps output consistent across toolchains.
> +
> +gdb_test_no_output "set filename-display basename"
> +
> gdb_test "frame" "#0 *main \\(\\) at $testfile\\.c:$decimal.*" \
> "frame in main"
>
> --
> 2.43.0