| Message ID | 1522128575-5326-11-git-send-email-yamada.masahiro@socionext.com |
|---|---|
| State | New |
| Headers | show |
| Series | kconfig: move compiler capability tests to Kconfig | expand |
On Mon, Mar 26, 2018 at 10:29 PM, Masahiro Yamada <yamada.masahiro@socionext.com> wrote: > 'cc-option' will be the most frequently used macro. It evaluates to 'y' > if the given argument is supported by the compiler, or 'n' otherwise. > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Kees Cook <keescook@chromium.org> > --- > > Changes in v2: > - Implement 'success' as a macro > > init/Kconfig | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/init/Kconfig b/init/Kconfig > index 0d6fe20..c456030 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -8,6 +8,12 @@ config DEFCONFIG_LIST > default ARCH_DEFCONFIG > default "arch/$ARCH/defconfig" > > +# expanded to y if the command exits with 0, n otherwise > +macro success $(shell ($(1) && echo y) || echo n) > + > +# expanded to y if the given compiler flag is supported, n otherwise > +macro cc-option $(success $CC -Werror $(1) -c -x c /dev/null -o /dev/null) This should be fine since most cc-option uses are quite simple. The specialized per-arch and other-flag-dependency checks can just continue to live in Makefile if we actually need them. -Kees -- Kees Cook Pixel Security
On Tue, Mar 27, 2018 at 7:29 AM, Masahiro Yamada <yamada.masahiro@socionext.com> wrote: > 'cc-option' will be the most frequently used macro. It evaluates to 'y' > if the given argument is supported by the compiler, or 'n' otherwise. > > Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> > --- > > Changes in v2: > - Implement 'success' as a macro > > init/Kconfig | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/init/Kconfig b/init/Kconfig > index 0d6fe20..c456030 100644 > --- a/init/Kconfig > +++ b/init/Kconfig > @@ -8,6 +8,12 @@ config DEFCONFIG_LIST > default ARCH_DEFCONFIG > default "arch/$ARCH/defconfig" > > +# expanded to y if the command exits with 0, n otherwise > +macro success $(shell ($(1) && echo y) || echo n) > + > +# expanded to y if the given compiler flag is supported, n otherwise > +macro cc-option $(success $CC -Werror $(1) -c -x c /dev/null -o /dev/null) > + > config CONSTRUCTORS > bool > depends on !UML > -- > 2.7.4 > Reviewed-by: Ulf Magnusson <ulfalizer@gmail.com> Some other tests (e.g. scripts/*-stack-protector.sh) also pass -S and -O0 and stuff to speed things up. Feels like that could lead to gotchas though. -S does help a bit at least: $ time gcc -c -x c /dev/null -o /dev/null real 0m0.020s user 0m0.013s sys 0m0.007s $ time gcc -S -x c /dev/null -o /dev/null real 0m0.012s user 0m0.009s sys 0m0.003s
diff --git a/init/Kconfig b/init/Kconfig index 0d6fe20..c456030 100644 --- a/init/Kconfig +++ b/init/Kconfig @@ -8,6 +8,12 @@ config DEFCONFIG_LIST default ARCH_DEFCONFIG default "arch/$ARCH/defconfig" +# expanded to y if the command exits with 0, n otherwise +macro success $(shell ($(1) && echo y) || echo n) + +# expanded to y if the given compiler flag is supported, n otherwise +macro cc-option $(success $CC -Werror $(1) -c -x c /dev/null -o /dev/null) + config CONSTRUCTORS bool depends on !UML
'cc-option' will be the most frequently used macro. It evaluates to 'y' if the given argument is supported by the compiler, or 'n' otherwise. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> --- Changes in v2: - Implement 'success' as a macro init/Kconfig | 6 ++++++ 1 file changed, 6 insertions(+) -- 2.7.4