Subject: Re: [PATCH] powerpc: disable sparse for lib/xor_vmx.c

From: Balbir Singh <[email-masked]>
Date: Tue, 26 Apr 2016 16:42:47 +1000

On 26/04/16 14:58, Daniel Axtens wrote:
> Sparse doesn't seem to be passing -maltivec around properly, leading
> to lots of errors:
> 
> .../include/altivec.h:34:2: error: Use the "-maltivec" flag to enable PowerPC AltiVec support
> arch/powerpc/lib/xor_vmx.c:27:16: error: Expected ; at end of declaration
> arch/powerpc/lib/xor_vmx.c:27:16: error: got signed
> arch/powerpc/lib/xor_vmx.c:60:9: error: No right hand side of '*'-expression
> arch/powerpc/lib/xor_vmx.c:60:9: error: Expected ; at end of statement
> arch/powerpc/lib/xor_vmx.c:60:9: error: got v1_in
> ...
> arch/powerpc/lib/xor_vmx.c:87:9: error: too many errors
> 
> Disable sparse checking for xor_vmx.c.
> 
> Signed-off-by: Daniel Axtens <[email-masked]>
> ---
>  arch/powerpc/lib/xor_vmx.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/arch/powerpc/lib/xor_vmx.c b/arch/powerpc/lib/xor_vmx.c
> index 07f49f1568e5..eccf37db9512 100644
> --- a/arch/powerpc/lib/xor_vmx.c
> +++ b/arch/powerpc/lib/xor_vmx.c
> @@ -17,6 +17,16 @@
>   *
>   * Author: Anton Blanchard <[email-masked]>
>   */
> +
> +/*
> + * Sparse (as at v0.5.0) gets very, very confused by this file.
> + * Just disable it.
> + */
> +#ifdef __CHECKER__
> +#undef __CHECKER__
> +#warning "Sparse checking disabled for this file"
> +#endif
> +
>  #include <altivec.h>
>  

Isn't it better to do this

#if !defined(__CHECKER__)
#include <altivec.h>
#else
#define vec_xor(a, b) a ^ b
#endif

This will probably let to sparse check the rest of the file. I've not checked it, just recommending it.
See how it goes

>  #include <linux/preempt.h>
>