Re: [Qemu-devel] [PATCH] target-alpha: Avoid gcc 6.1 werror for linux-user

[Paolo Bonzini]

On 17/06/2016 21:46, Richard Henderson wrote:
> Using gcc 6.1 for alpha-linux-user target we see the following build error:
> 
> .../target-alpha/translate.c: In function ‘in_superpage’:
> .../target-alpha/translate.c:454:52: error: self-comparison always evaluates 
> to true [-Werror=tautological-compare]
>              && addr >> TARGET_VIRT_ADDR_SPACE_BITS == addr >> 63);
> 
> Reported-by: Pranith Kumar <address@hidden>
> Signed-off-by: Richard Henderson <address@hidden>
> ---
>  target-alpha/translate.c | 9 ++++++---
>  1 file changed, 6 insertions(+), 3 deletions(-)
> 
> diff --git a/target-alpha/translate.c b/target-alpha/translate.c
> index f9b2426..051b4b7 100644
> --- a/target-alpha/translate.c
> +++ b/target-alpha/translate.c
> @@ -448,10 +448,13 @@ static ExitStatus gen_store_conditional(DisasContext 
> *ctx, int ra, int rb,
>  
>  static bool in_superpage(DisasContext *ctx, int64_t addr)
>  {
> +#ifndef CONFIG_USER_ONLY
>      return ((ctx->tb->flags & TB_FLAGS_USER_MODE) == 0
> -            && addr < 0
> -            && ((addr >> 41) & 3) == 2
> -            && addr >> TARGET_VIRT_ADDR_SPACE_BITS == addr >> 63);
> +            && addr >> TARGET_VIRT_ADDR_SPACE_BITS == -1
> +            && ((addr >> 41) & 3) == 2);
> +#else
> +    return false;
> +#endif
>  }
>  
>  static bool use_goto_tb(DisasContext *ctx, uint64_t dest)
> 

Peter, can you apply this as a build-breakage fix?  (Fedora 24 is now
out and has this bug).

Paolo