Messages in this thread | | | From | Nick Desaulniers <> | Date | Tue, 20 Jul 2021 13:56:51 -0700 | Subject | Re: [PATCH] compiler_attributes.h: move __compiletime_{error|warning} |
| |
On Tue, Jul 20, 2021 at 12:07 PM Nathan Chancellor <nathan@kernel.org> wrote: > > On 7/20/2021 11:04 AM, Nick Desaulniers wrote: > > I'm working on adding support for __attribute__((__error__(""))) and > > __attribute__((__warning__(""))) to Clang. To make use of these in > > __compiletime_error and __compiletime_warning (as used by BUILD_BUG and > > friends) for newer clang and detect/fallback for older versions of > > clang, move these to compiler_attributes.h and guard them with > > __has_attribute preprocessor guards. > > > > Link: https://reviews.llvm.org/D106030 > > Link: https://bugs.llvm.org/show_bug.cgi?id=16428 > > Link: https://github.com/ClangBuiltLinux/linux/issues/1173 > > Signed-off-by: Nick Desaulniers <ndesaulniers@google.com> > > --- > > Note that this feature hasn't landed yet in clang! I expect it to land > > in clang-13 though soon. We can still move this in anticipation of the > > feature landing, though perhaps the versions might not be precise if it > > slips to clang-14 (though I don't anticipate that). > > > > include/linux/compiler-gcc.h | 3 --- > > include/linux/compiler_attributes.h | 30 ++++++++++++++++++++++++++--- > > include/linux/compiler_types.h | 6 ------ > > 3 files changed, 27 insertions(+), 12 deletions(-) > > > > diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h > > index cb9217fc60af..21c36b69eb06 100644 > > --- a/include/linux/compiler-gcc.h > > +++ b/include/linux/compiler-gcc.h > > @@ -43,9 +43,6 @@ > > > > #define __compiletime_object_size(obj) __builtin_object_size(obj, 0) > > > > -#define __compiletime_warning(message) __attribute__((__warning__(message))) > > -#define __compiletime_error(message) __attribute__((__error__(message))) > > - > > #if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__) > > #define __latent_entropy __attribute__((latent_entropy)) > > #endif > > diff --git a/include/linux/compiler_attributes.h b/include/linux/compiler_attributes.h > > index 2487be0e7199..5f474b593425 100644 > > --- a/include/linux/compiler_attributes.h > > +++ b/include/linux/compiler_attributes.h > > @@ -30,14 +30,16 @@ > > # define __GCC4_has_attribute___assume_aligned__ 1 > > # define __GCC4_has_attribute___copy__ 0 > > # define __GCC4_has_attribute___designated_init__ 0 > > +# define __GCC4_has_attribute___error__ 1 > > # define __GCC4_has_attribute___externally_visible__ 1 > > +# define __GCC4_has_attribute___fallthrough__ 0 > > # define __GCC4_has_attribute___no_caller_saved_registers__ 0 > > -# define __GCC4_has_attribute___noclone__ 1 > > # define __GCC4_has_attribute___no_profile_instrument_function__ 0 > > -# define __GCC4_has_attribute___nonstring__ 0 > > # define __GCC4_has_attribute___no_sanitize_address__ 1 > > # define __GCC4_has_attribute___no_sanitize_undefined__ 1 > > -# define __GCC4_has_attribute___fallthrough__ 0 > > +# define __GCC4_has_attribute___noclone__ 1 > > +# define __GCC4_has_attribute___nonstring__ 0 > > +# define __GCC4_has_attribute___warning__ 1 > > #endif > > > > /* > > @@ -137,6 +139,17 @@ > > # define __designated_init > > #endif > > > > +/* > > + * Optional: only supported since clang >= 13.0 > > + * > > + * gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-error-function-attribute > > + */ > > +#if __has_attribute(__error__) > > +# define __compiletime_error(msg) __attribute__((__error__(msg))) > > +#else > > +# define __compiletime_error(msg) > > +#endif > > + > > /* > > * Optional: not supported by clang > > * > > @@ -298,6 +311,17 @@ > > */ > > #define __must_check __attribute__((__warn_unused_result__)) > > > > +/* > > + * Optional: only supported since clang >= 13.0 > > + * > > + * gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-warning-function-attribute > > + */ > > +#if __has_attribute(warning) > > Should this be > > #if __has_attribute(__warning__) > > ?
Yes. :-X
> > > +# define __compiletime_warning(msg) __attribute__((__warning__(msg))) > > +#else > > +# define __compiletime_warning(msg) > > +#endif > > + > > /* > > * gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-weak-function-attribute > > * gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html#index-weak-variable-attribute > > diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h > > index e4ea86fc584d..b6ff83a714ca 100644 > > --- a/include/linux/compiler_types.h > > +++ b/include/linux/compiler_types.h > > @@ -294,12 +294,6 @@ struct ftrace_likely_data { > > #ifndef __compiletime_object_size > > # define __compiletime_object_size(obj) -1 > > #endif > > -#ifndef __compiletime_warning > > -# define __compiletime_warning(message) > > -#endif > > -#ifndef __compiletime_error > > -# define __compiletime_error(message) > > -#endif > > > > #ifdef __OPTIMIZE__ > > # define __compiletime_assert(condition, msg, prefix, suffix) \ > >
-- Thanks, ~Nick Desaulniers
| |