Re: [PATCH] gdb.dwarf2: Fix fission-dw-form-strx.exp workflow

[Simon Marchi <simark@simark.ca>]

On 4/23/26 6:37 AM, Bratislav Filipovic wrote:
> The test was using gdb_compile_shlib to create the .dwo file, which
> runs the linker. This is incorrect for DWARF fission - .dwo files
> should be created by objcopy extraction, not linking.
> 
> Per commit 6a29913eeb9, "it was a bad idea to generate a .dwo file
> using the linker, since the idea behind .dwo files is that they do
> not need to be linked."
> 
> GCC's assembler doesn't set the SHF_EXCLUDE flag on .debug_*.dwo
> sections, so the linker preserves them in the output. Clang's
> assembler sets SHF_EXCLUDE, causing the linker to exclude these
> sections. Both approaches are valid, but only the GCC approach
> happens to work with this test's incorrect use of the linker.
> 
> Rewrite the test to use build_executable_and_dwo_files with the
> split-dwo option, matching all other fission-*.exp tests. This uses
> objcopy to properly extract .dwo sections without involving the
> linker.
> 
> Changes:
> - Use build_executable_and_dwo_files instead of gdb_compile_shlib
> - Generate both skeleton and DWO CUs in single Dwarf::assemble block
> - Add debug_str_offsets section for DW_FORM_strx support
> - Add is_remote host check (required for objcopy-based workflow)
> - Fix DW_AT_dwo_name to match generated filename
> 
> Tested: GCC 13.3.0, Clang-23 (passes)

Thanks, that LGTM.

Approved-By: Simon Marchi <simon.marchi@efficios.com>

Just a nit: when sending a version 2 of a patch or patch series, pass
`-v2` to git-send-email to make it add "v2" in the subject prefix.

However, it seems that you used --in-reply-to to keep the new patch in
the same thread as the original on, that is very nice and thoughtful,
thank you.

Simon