Re: [PATCH v2 3/5] Makefile.compiler: replace cc-ifversion with compiler-specific macros
On Thu, Sep 1, 2022 at 3:44 AM Nick Desaulniers wrote: > > cc-ifversion is GCC specific. Replace it with compiler specific > variants. Update the users of cc-ifversion to use these new macros. > Provide a helper for checking compiler versions for GCC and Clang > simultaneously, that will be used in a follow up patch. > > Cc: Jonathan Corbet > Cc: linux-...@vger.kernel.org > Cc: amd-gfx@lists.freedesktop.org > Cc: dri-de...@lists.freedesktop.org > Link: https://github.com/ClangBuiltLinux/linux/issues/350 > Link: > https://lore.kernel.org/llvm/CAGG=3QWSAUakO42kubrCap8fp-gm1ERJJAYXTnP1iHk_wrH=b...@mail.gmail.com/ > Suggested-by: Bill Wendling > Signed-off-by: Nick Desaulniers > --- > Changes v1 -> v2: > * New patch. > > Documentation/kbuild/makefiles.rst | 44 +++-- > Makefile| 4 +- > drivers/gpu/drm/amd/display/dc/dml/Makefile | 12 ++ > scripts/Makefile.compiler | 15 +-- > 4 files changed, 49 insertions(+), 26 deletions(-) > > diff --git a/Documentation/kbuild/makefiles.rst > b/Documentation/kbuild/makefiles.rst > index 11a296e52d68..e46f5b45c422 100644 > --- a/Documentation/kbuild/makefiles.rst > +++ b/Documentation/kbuild/makefiles.rst > @@ -682,22 +682,42 @@ more details, with real examples. > In the above example, -Wno-unused-but-set-variable will be added to > KBUILD_CFLAGS only if gcc really accepts it. > > -cc-ifversion > - cc-ifversion tests the version of $(CC) and equals the fourth > parameter > - if version expression is true, or the fifth (if given) if the version > - expression is false. > +gcc-min-version > + gcc-min-version tests if the value of $(CONFIG_GCC_VERSION) is > greater than > + or equal to the provided value and evaluates to y if so. > > Example:: > > - #fs/reiserfs/Makefile > - ccflags-y := $(call cc-ifversion, -lt, 0402, -O1) > + cflags-$(call gcc-min-version, 70100) := -foo > > - In this example, ccflags-y will be assigned the value -O1 if the > - $(CC) version is less than 4.2. > - cc-ifversion takes all the shell operators: > - -eq, -ne, -lt, -le, -gt, and -ge > - The third parameter may be a text as in this example, but it may also > - be an expanded variable or a macro. > + In this example, cflags-y will be assigned the value -foo if $(CC) is > gcc and > + $(CONFIG_GCC_VERSION) is >= 7.1. > + > +clang-min-version > + clang-min-version tests if the value of $(CONFIG_CLANG_VERSION) is > greater > + than or equal to the provided value and evaluates to y if so. > + > + Example:: > + > + cflags-$(call clang-min-version, 11) := -foo > + > + In this example, cflags-y will be assigned the value -foo if $(CC) is > clang > + and $(CONFIG_CLANG_VERSION) is >= 11.0.0. > + > +cc-min-version > + cc-min-version tests if the value of $(CONFIG_GCC_VERSION) is greater > + than or equal to the first value provided, or if the value of > + $(CONFIG_CLANG_VERSION) is greater than or equal to the second value > + provided, and evaluates > + to y if so. > + > + Example:: > + > + cflags-$(call cc-min-version, 70100, 11) := -foo > + > + In this example, cflags-y will be assigned the value -foo if $(CC) is > gcc and > + $(CONFIG_GCC_VERSION) is >= 7.1, or if $(CC) is clang and > + $(CONFIG_CLANG_VERSION) is >= 11.0.0. > > cc-cross-prefix > cc-cross-prefix is used to check if there exists a $(CC) in path with > diff --git a/Makefile b/Makefile > index 952d354069a4..caa39ecb1136 100644 > --- a/Makefile > +++ b/Makefile > @@ -972,7 +972,7 @@ ifdef CONFIG_CC_IS_GCC > KBUILD_CFLAGS += -Wno-maybe-uninitialized > endif > > -ifdef CONFIG_CC_IS_GCC > +ifeq ($(call gcc-min-version, 90100),y) > # The allocators already balk at large sizes, so silence the compiler > # warnings for bounds checks involving those possible values. While > # -Wno-alloc-size-larger-than would normally be used here, earlier versions > @@ -984,7 +984,7 @@ ifdef CONFIG_CC_IS_GCC > # ignored, continuing to default to PTRDIFF_MAX. So, left with no other > # choice, we must perform a versioned check to disable this warning. > # https://lore.kernel.org/lkml/20210824115859.187f2...@canb.auug.org.au > -KBUILD_CFLAGS += $(call cc-ifversion, -ge, 0901, -Wno-alloc-size-larger-than) > +KBUILD_CFLAGS += -Wno-alloc-size-larger-than > endif > > # disable invalid "can't wrap" optimizations for signed / pointers > diff --git a/drivers/gpu/drm/amd/display/dc/dml/Makefile > b/drivers/gpu/drm/amd/display/dc/dml/Makefile > index 86a3b5bfd699..d8ee4743b2e3 100644 > --- a/drivers/gpu/drm/amd/display/dc/dml/Makefile > +++ b/drivers/gpu/drm/amd/display/dc/dml/Makefile > @@ -33,20 +33,14 @@ ifdef CONFIG_PPC64 > dml_ccflags := -mhard-float -maltivec > endif > >
Re: [PATCH v2 3/5] Makefile.compiler: replace cc-ifversion with compiler-specific macros
On Wed, Aug 31, 2022 at 11:44:06AM -0700, Nick Desaulniers wrote: > cc-ifversion is GCC specific. Replace it with compiler specific > variants. Update the users of cc-ifversion to use these new macros. > Provide a helper for checking compiler versions for GCC and Clang > simultaneously, that will be used in a follow up patch. > > Cc: Jonathan Corbet > Cc: linux-...@vger.kernel.org > Cc: amd-gfx@lists.freedesktop.org > Cc: dri-de...@lists.freedesktop.org > Link: https://github.com/ClangBuiltLinux/linux/issues/350 > Link: > https://lore.kernel.org/llvm/CAGG=3QWSAUakO42kubrCap8fp-gm1ERJJAYXTnP1iHk_wrH=b...@mail.gmail.com/ > Suggested-by: Bill Wendling > Signed-off-by: Nick Desaulniers These are so much nicer. I find the name kind of awkward but the only thing I could come up with that sounded better was 'gcc-is-at-least' or 'clang-is-at-least' and I don't really feel like painting sheds today, it's hot outside :) Reviewed-by: Nathan Chancellor Some comments below. > --- > Changes v1 -> v2: > * New patch. > > Documentation/kbuild/makefiles.rst | 44 +++-- > Makefile| 4 +- > drivers/gpu/drm/amd/display/dc/dml/Makefile | 12 ++ > scripts/Makefile.compiler | 15 +-- > 4 files changed, 49 insertions(+), 26 deletions(-) > > diff --git a/Documentation/kbuild/makefiles.rst > b/Documentation/kbuild/makefiles.rst > index 11a296e52d68..e46f5b45c422 100644 > --- a/Documentation/kbuild/makefiles.rst > +++ b/Documentation/kbuild/makefiles.rst > @@ -682,22 +682,42 @@ more details, with real examples. > In the above example, -Wno-unused-but-set-variable will be added to > KBUILD_CFLAGS only if gcc really accepts it. > > -cc-ifversion > - cc-ifversion tests the version of $(CC) and equals the fourth parameter > - if version expression is true, or the fifth (if given) if the version > - expression is false. > +gcc-min-version > + gcc-min-version tests if the value of $(CONFIG_GCC_VERSION) is greater > than > + or equal to the provided value and evaluates to y if so. > > Example:: > > - #fs/reiserfs/Makefile > - ccflags-y := $(call cc-ifversion, -lt, 0402, -O1) > + cflags-$(call gcc-min-version, 70100) := -foo > > - In this example, ccflags-y will be assigned the value -O1 if the > - $(CC) version is less than 4.2. > - cc-ifversion takes all the shell operators: > - -eq, -ne, -lt, -le, -gt, and -ge > - The third parameter may be a text as in this example, but it may also > - be an expanded variable or a macro. > + In this example, cflags-y will be assigned the value -foo if $(CC) is > gcc and > + $(CONFIG_GCC_VERSION) is >= 7.1. > + > +clang-min-version > + clang-min-version tests if the value of $(CONFIG_CLANG_VERSION) is > greater > + than or equal to the provided value and evaluates to y if so. > + > + Example:: > + > + cflags-$(call clang-min-version, 11) := -foo > + > + In this example, cflags-y will be assigned the value -foo if $(CC) is > clang > + and $(CONFIG_CLANG_VERSION) is >= 11.0.0. > + > +cc-min-version > + cc-min-version tests if the value of $(CONFIG_GCC_VERSION) is greater > + than or equal to the first value provided, or if the value of > + $(CONFIG_CLANG_VERSION) is greater than or equal to the second value > + provided, and evaluates > + to y if so. > + > + Example:: > + > + cflags-$(call cc-min-version, 70100, 11) := -foo > + > + In this example, cflags-y will be assigned the value -foo if $(CC) is > gcc and > + $(CONFIG_GCC_VERSION) is >= 7.1, or if $(CC) is clang and > + $(CONFIG_CLANG_VERSION) is >= 11.0.0. > > cc-cross-prefix > cc-cross-prefix is used to check if there exists a $(CC) in path with > diff --git a/Makefile b/Makefile > index 952d354069a4..caa39ecb1136 100644 > --- a/Makefile > +++ b/Makefile > @@ -972,7 +972,7 @@ ifdef CONFIG_CC_IS_GCC > KBUILD_CFLAGS += -Wno-maybe-uninitialized > endif > > -ifdef CONFIG_CC_IS_GCC > +ifeq ($(call gcc-min-version, 90100),y) > # The allocators already balk at large sizes, so silence the compiler > # warnings for bounds checks involving those possible values. While > # -Wno-alloc-size-larger-than would normally be used here, earlier versions > @@ -984,7 +984,7 @@ ifdef CONFIG_CC_IS_GCC > # ignored, continuing to default to PTRDIFF_MAX. So, left with no other > # choice, we must perform a versioned check to disable this warning. > # https://lore.kernel.org/lkml/20210824115859.187f2...@canb.auug.org.au > -KBUILD_CFLAGS += $(call cc-ifversion, -ge, 0901, -Wno-alloc-size-larger-than) > +KBUILD_CFLAGS += -Wno-alloc-size-larger-than > endif It might be interesting to move this up to where KBUILD_CFLAGS-y is used to make it: KBUILD_CFLAGS-$(call gcc-min-version, 90100) += -Wno-alloc-size-larger-than But the comment
