Re: [PATCH] sparse: update __builtin_object_size() prototype

[Luc Van Oostenryck <luc.vanoostenryck@gmail.com>]

On Wed, Sep 21, 2016 at 10:13:58AM -0400, Lance Richardson wrote:
> Sparse emits a large number of warnings for the linux kernel source
> tree of the form:
>     ./arch/x86/include/asm/uaccess.h:735:18: \
>         warning: incorrect type in argument 1 (different modifiers)
>     ./arch/x86/include/asm/uaccess.h:735:18:    expected void *<noident>
>     ./arch/x86/include/asm/uaccess.h:735:18:    got void const *from
> 
> Fix by making the first parameter to __builtin_object_size()
> type "const void *" instead of "void *", which is consistent with GCC
> behavior (the prototype for this builtin in GCC documentation is evidently
> incorrect).
> 
> Signed-off-by: Lance Richardson <lrichard@redhat.com>
> ---
>  lib.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/lib.c b/lib.c
> index aa2af68..122dd6f 100644
> --- a/lib.c
> +++ b/lib.c
> @@ -917,7 +917,7 @@ void declare_builtin_functions(void)
>  	add_pre_buffer("extern long double __builtin_nanl(const char *);\n");
>  
>  	/* And some __FORTIFY_SOURCE ones.. */
> -	add_pre_buffer ("extern __SIZE_TYPE__ __builtin_object_size(void *, int);\n");
> +	add_pre_buffer ("extern __SIZE_TYPE__ __builtin_object_size(const void *, int);\n");
>  	add_pre_buffer ("extern void * __builtin___memcpy_chk(void *, const void *, __SIZE_TYPE__, __SIZE_TYPE__);\n");
>  	add_pre_buffer ("extern void * __builtin___memmove_chk(void *, const void *, __SIZE_TYPE__, __SIZE_TYPE__);\n");
>  	add_pre_buffer ("extern void * __builtin___mempcpy_chk(void *, const void *, __SIZE_TYPE__, __SIZE_TYPE__);\n");
> -- 

Acked-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>


Chris, can you please take this patch (or Johannes' one).
When compiling the kernel, there is more than 2000 false warnings
only for the uaccess.h case described here above.

Luc