| Message ID | 20210817002109.2736222-8-ndesaulniers@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | kbuild: remove cc-option-yn | expand |
On 8/16/2021 5:21 PM, 'Nick Desaulniers' via Clang Built Linux wrote: > cc-option-yn can be replaced with cc-option. ie. > Checking for support: > ifeq ($(call cc-option-yn,$(FLAG)),y) > becomes: > ifneq ($(call cc-option,$(FLAG)),) > > Checking for lack of support: > ifeq ($(call cc-option-yn,$(FLAG)),n) > becomes: > ifeq ($(call cc-option,$(FLAG)),) > > This allows us to remove cc-option-yn. Do so and update the docs with > examples. > > Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> > --- > Documentation/kbuild/makefiles.rst | 22 +++++++++------------- > scripts/Makefile.compiler | 5 ----- > 2 files changed, 9 insertions(+), 18 deletions(-) > > diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst > index db3af0b45baf..4538c36d8df0 100644 > --- a/Documentation/kbuild/makefiles.rst > +++ b/Documentation/kbuild/makefiles.rst > @@ -650,24 +650,20 @@ more details, with real examples. > -march=pentium-mmx if supported by $(CC), otherwise -march=i586. > The second argument to cc-option is optional, and if omitted, > cflags-y will be assigned no value if first option is not supported. > - Note: cc-option uses KBUILD_CFLAGS for $(CC) options > + Note: cc-option uses KBUILD_CFLAGS for $(CC) options. > > - cc-option-yn > - cc-option-yn is used to check if gcc supports a given option > - and return 'y' if supported, otherwise 'n'. > + cc-option can be combined with conditionals to perform actions based on tool > + support. > > Example:: > > - #arch/ppc/Makefile > - biarch := $(call cc-option-yn, -m32) > - aflags-$(biarch) += -a32 > - cflags-$(biarch) += -m32 > + ifneq ($(call cc-option,$(FLAG)),) > + # $(FLAG) is supported > > - In the above example, $(biarch) is set to y if $(CC) supports the -m32 > - option. When $(biarch) equals 'y', the expanded variables $(aflags-y) > - and $(cflags-y) will be assigned the values -a32 and -m32, > - respectively. > - Note: cc-option-yn uses KBUILD_CFLAGS for $(CC) options > + Or:: > + > + ifeq ($(call cc-option,$(FLAG)),) > + # $(FLAG) is not supported > > cc-disable-warning > cc-disable-warning checks if gcc supports a given warning and returns > diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler > index 86ecd2ac874c..c19c0b544c0f 100644 > --- a/scripts/Makefile.compiler > +++ b/scripts/Makefile.compiler > @@ -51,11 +51,6 @@ __cc-option = $(call try-run,\ > cc-option = $(call __cc-option, $(CC),\ > $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2)) > > -# cc-option-yn > -# Usage: flag := $(call cc-option-yn,-march=winchip-c6) > -cc-option-yn = $(call try-run,\ > - $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) > - > # cc-disable-warning > # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) > cc-disable-warning = $(call try-run,\ >
diff --git a/Documentation/kbuild/makefiles.rst b/Documentation/kbuild/makefiles.rst index db3af0b45baf..4538c36d8df0 100644 --- a/Documentation/kbuild/makefiles.rst +++ b/Documentation/kbuild/makefiles.rst @@ -650,24 +650,20 @@ more details, with real examples. -march=pentium-mmx if supported by $(CC), otherwise -march=i586. The second argument to cc-option is optional, and if omitted, cflags-y will be assigned no value if first option is not supported. - Note: cc-option uses KBUILD_CFLAGS for $(CC) options + Note: cc-option uses KBUILD_CFLAGS for $(CC) options. - cc-option-yn - cc-option-yn is used to check if gcc supports a given option - and return 'y' if supported, otherwise 'n'. + cc-option can be combined with conditionals to perform actions based on tool + support. Example:: - #arch/ppc/Makefile - biarch := $(call cc-option-yn, -m32) - aflags-$(biarch) += -a32 - cflags-$(biarch) += -m32 + ifneq ($(call cc-option,$(FLAG)),) + # $(FLAG) is supported - In the above example, $(biarch) is set to y if $(CC) supports the -m32 - option. When $(biarch) equals 'y', the expanded variables $(aflags-y) - and $(cflags-y) will be assigned the values -a32 and -m32, - respectively. - Note: cc-option-yn uses KBUILD_CFLAGS for $(CC) options + Or:: + + ifeq ($(call cc-option,$(FLAG)),) + # $(FLAG) is not supported cc-disable-warning cc-disable-warning checks if gcc supports a given warning and returns diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler index 86ecd2ac874c..c19c0b544c0f 100644 --- a/scripts/Makefile.compiler +++ b/scripts/Makefile.compiler @@ -51,11 +51,6 @@ __cc-option = $(call try-run,\ cc-option = $(call __cc-option, $(CC),\ $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2)) -# cc-option-yn -# Usage: flag := $(call cc-option-yn,-march=winchip-c6) -cc-option-yn = $(call try-run,\ - $(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n) - # cc-disable-warning # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable) cc-disable-warning = $(call try-run,\
cc-option-yn can be replaced with cc-option. ie. Checking for support: ifeq ($(call cc-option-yn,$(FLAG)),y) becomes: ifneq ($(call cc-option,$(FLAG)),) Checking for lack of support: ifeq ($(call cc-option-yn,$(FLAG)),n) becomes: ifeq ($(call cc-option,$(FLAG)),) This allows us to remove cc-option-yn. Do so and update the docs with examples. Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> --- Documentation/kbuild/makefiles.rst | 22 +++++++++------------- scripts/Makefile.compiler | 5 ----- 2 files changed, 9 insertions(+), 18 deletions(-)