Also, please cc me and the llvm mailing list on all changes to
include/linux/compiler-clang.h. I see now on lore there's further
patches here than just this single patch I was cc'ed on.
On Mon, Mar 7, 2022 at 11:25 AM Nick Desaulniers
<ndesaulniers@xxxxxxxxxx> wrote:
>
> On Fri, Mar 4, 2022 at 2:47 PM Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx> wrote:
> >
> > From: Nathan Chancellor <nathan@xxxxxxxxxx>
> >
> > Add __diag macros similar to those in compiler-gcc.h, so that warnings
> > that need to be adjusted for specific cases but not globally can be
> > ignored when building with clang.
> >
> > Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
> > Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
> > Cc: llvm@xxxxxxxxxxxxxxx
> > Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx>
> > [ Kartikeya: wrote commit message ]
> > Signed-off-by: Kumar Kartikeya Dwivedi <memxor@xxxxxxxxx>
> > ---
> > include/linux/compiler-clang.h | 22 ++++++++++++++++++++++
> > 1 file changed, 22 insertions(+)
> >
> > diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h
> > index 3c4de9b6c6e3..f1aa41d520bd 100644
> > --- a/include/linux/compiler-clang.h
> > +++ b/include/linux/compiler-clang.h
>
> The equivalent functionality for GCC has
> 357 #ifndef __diag_GCC
> 358 #define __diag_GCC(version, severity, string)
> 359 #endif
> in include/linux/compiler_types.h. Should this patch as well? (at
> least #define __diag_clang`)?
>
> > @@ -68,3 +68,25 @@
> >
> > #define __nocfi __attribute__((__no_sanitize__("cfi")))
> > #define __cficanonical __attribute__((__cfi_canonical_jump_table__))
> > +
> > +/*
> > + * Turn individual warnings and errors on and off locally, depending
> > + * on version.
> > + */
> > +#define __diag_clang(version, severity, s) \
> > + __diag_clang_ ## version(__diag_clang_ ## severity s)
> > +
> > +/* Severity used in pragma directives */
> > +#define __diag_clang_ignore ignored
> > +#define __diag_clang_warn warning
> > +#define __diag_clang_error error
>
> These severities match GCC. I wonder if rather than copy+pasting these
> over, we could rework __diag_ignore, __diag_warn, and __diag_error to
> not invoke a compiler-suffixed macro and rather pass the compiler
> along (or make it implicit since we know CONFIG_CC_IS_CLANG vs
> CONFIG_CC_IS_GCC)? We can probably land this than follow up on better
> code-reuse between compilers for diagnostics.
>
> > +
> > +#define __diag_str1(s) #s
> > +#define __diag_str(s) __diag_str1(s)
> > +#define __diag(s) _Pragma(__diag_str(clang diagnostic s))
> > +
> > +#if CONFIG_CLANG_VERSION >= 110000
> > +#define __diag_clang_11(s) __diag(s)
> > +#else
> > +#define __diag_clang_11(s)
> > +#endif
> > --
> > 2.35.1
> >
>
>
> --
> Thanks,
> ~Nick Desaulniers
--
Thanks,
~Nick Desaulniers
