Re: [PATCH v2] meson: Use -fno-sanitize=function when available

[Thomas Huth <thuth@redhat.com>]

On 29/07/2024 01.54, Richard Henderson wrote:
> On 7/29/24 01:44, Akihiko Odaki wrote:
>> Commit 23ef50ae2d0c (".gitlab-ci.d/buildtest.yml: Use
>> -fno-sanitize=function in the clang-system job") adds
>> -fno-sanitize=function for the CI but doesn't add the flag in the
>> other context. Add it to meson.build for such. It is not removed from
>> .gitlab-ci.d/buildtest.yml because -fno-sanitize=function in meson.build
>> does not affect --extra-cflags due to argument ordering.
>>
>> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
>> ---
>> Changes in v2:
>> - Dropped the change of: .gitlab-ci.d/buildtest.yml
>> - Link to v1: 
>> https://lore.kernel.org/r/20240714-function-v1-1-cc2acb4171ba@daynix.com
>> ---
>>   meson.build                | 1 +
>>   .gitlab-ci.d/buildtest.yml | 1 -
>>   2 files changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/meson.build b/meson.build
>> index 5613b62a4f42..a4169c572ba9 100644
>> --- a/meson.build
>> +++ b/meson.build
>> @@ -609,6 +609,7 @@ if host_os != 'openbsd' and \
>>   endif
>>   qemu_common_flags += cc.get_supported_arguments(hardening_flags)
>> +qemu_common_flags += cc.get_supported_arguments('-fno-sanitize=function')
>>   add_global_arguments(qemu_common_flags, native: false, language: 
>> all_languages)
>>   add_global_link_arguments(qemu_ldflags, native: false, language: 
>> all_languages)
>> diff --git a/.gitlab-ci.d/buildtest.yml b/.gitlab-ci.d/buildtest.yml
>> index aa327824052d..d83e50abd933 100644
>> --- a/.gitlab-ci.d/buildtest.yml
>> +++ b/.gitlab-ci.d/buildtest.yml
>> @@ -430,7 +430,6 @@ clang-system:
>>       IMAGE: fedora
>>       CONFIGURE_ARGS: --cc=clang --cxx=clang++
>>         --extra-cflags=-fsanitize=undefined 
>> --extra-cflags=-fno-sanitize-recover=undefined
>> -      --extra-cflags=-fno-sanitize=function
>>       TARGETS: alpha-softmmu arm-softmmu m68k-softmmu mips64-softmmu 
>> s390x-softmmu
>>       MAKE_CHECK_ARGS: check-qtest check-tcg
>>
>> ---
>> base-commit: 93b799fafd9170da3a79a533ea6f73a18de82e22
>> change-id: 20240714-function-7d32c723abbc
>>
>> Best regards,
> 
> Doesn't work, because --extra-cflags comes last and overrides it.
> 
> I think we need to drop -fsanitize=undefined from --extra-cflags as well, 
> and use --enable-sanitizers.  I think it should be ok to leave 
> -fno-sanitize-recover=undefined in extra.

That could be a solution, too, but I think the change in meson.build should 
then also be moved to the spot where -fsanitize=undefined is added.

  Thomas