Re: [PATCH 20/30] meson: prepare move of QEMU_CFLAGS to meson

[Marc-André Lureau]

On Fri, Dec 9, 2022 at 3:34 PM Paolo Bonzini <pbonzini@redhat.com> wrote:
>
> Clean up the handling of compiler flags in meson.build, splitting
> the general flags that should be included in subprojects as well,
> from warning flags that only apply to QEMU itself.  The two were
> mixed in both configure tests and meson tests.
>
> This split makes it easier to move the compiler tests piecewise
> from configure to Meson.
>
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>

> ---
>  meson.build | 53 +++++++++++++++++++++++++++++------------------------
>  1 file changed, 29 insertions(+), 24 deletions(-)
>
> diff --git a/meson.build b/meson.build
> index 99c1bde4d154..dac343d14797 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -190,10 +190,23 @@ endif
>  # Compiler flags #
>  ##################
>
> -qemu_cflags = config_host['QEMU_CFLAGS'].split()
> +qemu_common_flags = []
> +qemu_cflags = []
> +foreach arg : config_host['QEMU_CFLAGS'].split()
> +  if arg.startswith('-W')
> +    qemu_cflags += arg
> +  else
> +    qemu_common_flags += arg
> +  endif
> +endforeach
>  qemu_objcflags = config_host['QEMU_OBJCFLAGS'].split()
>  qemu_ldflags = config_host['QEMU_LDFLAGS'].split()
>
> +if get_option('gprof')
> +  qemu_common_flags += ['-p']
> +  qemu_ldflags += ['-p']
> +endif
> +
>  if get_option('prefer_static')
>    qemu_ldflags += get_option('b_pie') ? '-static-pie' : '-static'
>  endif
> @@ -207,10 +220,9 @@ if targetos == 'windows'
>    qemu_ldflags += cc.get_supported_link_arguments('-Wl,--dynamicbase', 
> '-Wl,--high-entropy-va')
>  endif
>
> -if get_option('gprof')
> -  qemu_cflags += ['-p']
> -  qemu_objcflags += ['-p']
> -  qemu_ldflags += ['-p']
> +# Exclude --warn-common with TSan to suppress warnings from the TSan 
> libraries.
> +if targetos != 'sunos' and not config_host.has_key('CONFIG_TSAN')
> +  qemu_ldflags += cc.get_supported_link_arguments('-Wl,--warn-common')
>  endif
>
>  # Specify linker-script with add_project_link_arguments so that it is not 
> placed
> @@ -230,8 +242,7 @@ if get_option('fuzzing')
>                    name: '-fsanitize-coverage-allowlist=/dev/null',
>                   args: ['-fsanitize-coverage-allowlist=/dev/null',
>                          '-fsanitize-coverage=trace-pc'] )
> -    
> add_global_arguments('-fsanitize-coverage-allowlist=instrumentation-filter',
> -                         native: false, language: all_languages)
> +    qemu_common_flags += 
> ['-fsanitize-coverage-allowlist=instrumentation-filter']
>    endif
>
>    if get_option('fuzzing_engine') == ''
> @@ -239,10 +250,8 @@ if get_option('fuzzing')
>      # compiled code.  To build non-fuzzer binaries with --enable-fuzzing, 
> link
>      # everything with fsanitize=fuzzer-no-link. Otherwise, the linker will be
>      # unable to bind the fuzzer-related callbacks added by instrumentation.
> -    add_global_arguments('-fsanitize=fuzzer-no-link',
> -                         native: false, language: all_languages)
> -    add_global_link_arguments('-fsanitize=fuzzer-no-link',
> -                              native: false, language: all_languages)
> +    qemu_common_flags += ['-fsanitize=fuzzer-no-link']
> +    qemu_ldflags += ['-fsanitize=fuzzer-no-link']
>      # For the actual fuzzer binaries, we need to link against the libfuzzer
>      # library. They need to be configurable, to support OSS-Fuzz
>      fuzz_exe_ldflags = ['-fsanitize=fuzzer']
> @@ -253,6 +262,9 @@ if get_option('fuzzing')
>    endif
>  endif
>
> +add_global_arguments(qemu_common_flags, native: false, language: 
> all_languages)
> +add_global_link_arguments(qemu_ldflags, native: false, language: 
> all_languages)
> +
>  # Check that the C++ compiler exists and works with the C compiler.
>  link_language = 'c'
>  linker = cc
> @@ -276,16 +288,9 @@ if 'cpp' in all_languages
>    endif
>  endif
>
> -# Exclude --warn-common with TSan to suppress warnings from the TSan 
> libraries.
> -if targetos != 'sunos' and not config_host.has_key('CONFIG_TSAN')
> -  qemu_ldflags += linker.get_supported_link_arguments('-Wl,--warn-common')
> -endif
> -
> -add_global_link_arguments(qemu_ldflags, native: false, language: 
> all_languages)
> -
> -add_global_arguments(qemu_cflags, native: false, language: 'c')
> -add_global_arguments(qemu_cxxflags, native: false, language: 'cpp')
> -add_global_arguments(qemu_objcflags, native: false, language: 'objc')
> +add_project_arguments(qemu_cflags, native: false, language: 'c')
> +add_project_arguments(qemu_cxxflags, native: false, language: 'cpp')
> +add_project_arguments(qemu_objcflags, native: false, language: 'objc')
>  if targetos == 'linux'
>    add_project_arguments('-isystem', meson.current_source_dir() / 
> 'linux-headers',
>                          '-isystem', 'linux-headers',
> @@ -3778,12 +3783,12 @@ link_args = get_option(link_language + '_link_args')
>  if link_args.length() > 0
>    summary_info += {'LDFLAGS':         ' '.join(link_args)}
>  endif
> -summary_info += {'QEMU_CFLAGS':       ' '.join(qemu_cflags)}
> +summary_info += {'QEMU_CFLAGS':       ' '.join(qemu_common_flags + 
> qemu_cflags)}
>  if 'cpp' in all_languages
> -  summary_info += {'QEMU_CXXFLAGS':     ' '.join(qemu_cxxflags)}
> +  summary_info += {'QEMU_CXXFLAGS':     ' '.join(qemu_common_flags + 
> qemu_cxxflags)}
>  endif
>  if 'objc' in all_languages
> -  summary_info += {'QEMU_OBJCFLAGS':    ' '.join(qemu_objcflags)}
> +  summary_info += {'QEMU_OBJCFLAGS':    ' '.join(qemu_common_flags + 
> qemu_objcflags)}
>  endif
>  summary_info += {'QEMU_LDFLAGS':      ' '.join(qemu_ldflags)}
>  summary_info += {'profiler':          get_option('profiler')}
> --
> 2.38.1
>
>


-- 
Marc-André Lureau