Hi Philippe,
On Fri, Feb 27, 2026 at 11:43:14AM +0100, Philippe Mathieu-Daudé wrote:
> gdb_static_features[] only contains strings, nothing target-specific.
> Instead of generating one file per target, generate a single file
> with a single gdb_static_features[] array.
>
> Signed-off-by: Philippe Mathieu-Daudé <[email protected]>
> ---
> meson.build | 14 --------------
> stubs/gdbstub.c => gdbstub/gdb-xml-stub.c | 0
> gdbstub/meson.build | 21 +++++++++++++++++++++
> stubs/meson.build | 2 --
> 4 files changed, 21 insertions(+), 16 deletions(-)
> rename stubs/gdbstub.c => gdbstub/gdb-xml-stub.c (100%)
>
> diff --git a/meson.build b/meson.build
> index 56a746fed00..875a0bb1999 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -4221,7 +4221,6 @@ if have_rust
> endif
>
>
> -feature_to_c = find_program('scripts/feature_to_c.py')
> rust_root_crate = find_program('scripts/rust/rust_root_crate.sh')
>
> if host_os == 'darwin'
> @@ -4301,19 +4300,6 @@ foreach target : target_dirs
> endif
> endif
>
> - if 'TARGET_XML_FILES' in config_target
> - gdbstub_xml_files = []
> - foreach gdbstub_xml : config_target['TARGET_XML_FILES'].split()
> - gdbstub_xml_files += 'gdbstub/gdb-xml/' + gdbstub_xml
> - endforeach
> - gdbstub_xml = custom_target(target + '-gdbstub-xml.c',
> - output: target + '-gdbstub-xml.c',
> - input: files(gdbstub_xml_files),
> - command: [feature_to_c, '@INPUT@'],
> - capture: true)
> - arch_srcs += gdbstub_xml
> - endif
> -
> if target in config_target_info
> arch_srcs += config_target_info[target]
> else
> diff --git a/stubs/gdbstub.c b/gdbstub/gdb-xml-stub.c
> similarity index 100%
> rename from stubs/gdbstub.c
> rename to gdbstub/gdb-xml-stub.c
> diff --git a/gdbstub/meson.build b/gdbstub/meson.build
> index 15c666f5752..a25a5ae9fbf 100644
> --- a/gdbstub/meson.build
> +++ b/gdbstub/meson.build
> @@ -4,6 +4,27 @@
> # types such as hwaddr.
> #
>
> +gdbstub_xml_files = []
> +foreach target : target_dirs
> + config_target = config_target_mak[target]
> + if 'TARGET_XML_FILES' in config_target
> + foreach gdbstub_xml : config_target['TARGET_XML_FILES'].split()
> + gdbstub_xml_files += 'gdb-xml/' + gdbstub_xml
Many XML files are shared across multiple targets. For example,
arm-core.xml appears in 5 targets (arm-softmmu, arm-linux-user,
arm-bsd-user, armeb-linux-user, arm-softmmu), riscv-64bit-fpu.xml
in 5 targets, etc.
Since there is no deduplication here, feature_to_c.py will receive
duplicate input files and generate duplicate GDBFeature entries in
gdb_static_features[]. While gdb_find_static_feature() does a
first-match linear scan so it won't break, it unnecessarily bloats
the binary.
Consider adding a dedup check:
```
if not gdbstub_xml_files.contains('gdb-xml/' + gdbstub_xml)
gdbstub_xml_files += 'gdb-xml/' + gdbstub_xml
endif
```
I tested this by actually running feature_to_c.py with the collected
XML files:
==Without deduplication:==
- Total references: 171
- Unique files: 60
- Duplicates: 111 (64.91%)
- Generated file: 669 KB, 17,777 lines
- Example: arm-core.xml appears 5 times at lines 1527, 2705, 3276, 3847, 4418
(each occurrence is 2400 bytes of identical code)
==With deduplication:==
- Generated file: 244 KB, 6,243 lines
- Space saved: 425 KB (63.57% reduction)
- No duplicate entries
---
Everything else looks good to me.
Reviewed-by: Chao Liu <[email protected]>
Thanks,
Chao
> + endforeach
> + endif
> +endforeach
> +if gdbstub_xml_files.length() > 0
> + feature_to_c = find_program('../scripts/feature_to_c.py')
> + gdbstub_xml = custom_target('gdbstub-xml.c',
> + output: 'gdbstub-xml.c',
> + input: files(gdbstub_xml_files),
> + command: [feature_to_c, '@INPUT@'],
> + capture: true)
> +else
> + gdbstub_xml = files('gdb-xml-stub.c')
> +endif
> +common_ss.add(gdbstub_xml)
> +
> # We build two versions of gdbstub, one for each mode
> user_ss.add(files(
> 'gdbstub.c',
> diff --git a/stubs/meson.build b/stubs/meson.build
> index 8a07059500d..1e0f6f47377 100644
> --- a/stubs/meson.build
> +++ b/stubs/meson.build
> @@ -89,8 +89,6 @@ if have_system
> endif
>
> if have_system or have_user
> - stub_ss.add(files('gdbstub.c'))
> -
> # Also included in have_system for --disable-tcg builds
> stub_ss.add(files('replay.c'))
>
> --
> 2.52.0
>
>
