Re: [PATCH 24/32] tools include: Add a __fallthrough statement

From: Joe Perches
Date: Thu Feb 09 2017 - 22:02:22 EST


On Thu, 2017-02-09 at 22:39 -0300, Arnaldo Carvalho de Melo wrote:
> From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
>
> For cases where implicit fall through case labels are intended,
> to let us inform that to gcc >= 7:

I believe this should be added to compiler_gcc.h

> diff --git a/tools/include/linux/compiler.h b/tools/include/linux/compiler.h
[]
> @@ -126,4 +126,13 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s
> #define WRITE_ONCE(x, val) \
> ({ union { typeof(x) __val; char __c[1]; } __u = { .__val = (val) }; __write_once_size(&(x), __u.__c, sizeof(x)); __u.__val; })
>
> +
> +#ifndef __fallthrough
> +# if defined(__GNUC__) && __GNUC__ >= 7
> +# define __fallthrough __attribute__ ((fallthrough))
> +# else
> +# define __fallthrough
> +# endif
> +#endif
> +
> #endif /* _TOOLS_LINUX_COMPILER_H */