Re: [Xen-devel] [PATCH] xen/arm: Surround HSR_SYSREG macro value with ()

[Julien Grall <julien.grall@xxxxxxxxxx>]

Hi,

Ping?

Cheers,

On 29/11/17 17:46, Julien Grall wrote:
> The value of the macro HCR_SYSREG is not surrounded by (). This means
> the behavior may change depend on how it is used.
>
> Thanksfully recent GCC will issue a warning for that.
>
> Signed-off-by: Julien Grall <julien.grall@xxxxxxxxxx>
>
> ---
>
> I am not aware of any "bad" usage today in Xen. This was found whilst
> playing with sysreg emulation and GCC complaining about the missing ().
> ---
>   xen/include/asm-arm/arm64/sysregs.h | 10 +++++-----
>   1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/xen/include/asm-arm/arm64/sysregs.h 
> b/xen/include/asm-arm/arm64/sysregs.h
> index 084d2a1e5d..1811234249 100644
> --- a/xen/include/asm-arm/arm64/sysregs.h
> +++ b/xen/include/asm-arm/arm64/sysregs.h
> @@ -32,11 +32,11 @@
>   
>   /* These are used to decode traps with HSR.EC==HSR_EC_SYSREG */
>   #define HSR_SYSREG(op0,op1,crn,crm,op2) \
> -    ((__HSR_SYSREG_##op0) << HSR_SYSREG_OP0_SHIFT) | \
> -    ((__HSR_SYSREG_##op1) << HSR_SYSREG_OP1_SHIFT) | \
> -    ((__HSR_SYSREG_##crn) << HSR_SYSREG_CRN_SHIFT) | \
> -    ((__HSR_SYSREG_##crm) << HSR_SYSREG_CRM_SHIFT) | \
> -    ((__HSR_SYSREG_##op2) << HSR_SYSREG_OP2_SHIFT)
> +    (((__HSR_SYSREG_##op0) << HSR_SYSREG_OP0_SHIFT) | \
> +     ((__HSR_SYSREG_##op1) << HSR_SYSREG_OP1_SHIFT) | \
> +     ((__HSR_SYSREG_##crn) << HSR_SYSREG_CRN_SHIFT) | \
> +     ((__HSR_SYSREG_##crm) << HSR_SYSREG_CRM_SHIFT) | \
> +     ((__HSR_SYSREG_##op2) << HSR_SYSREG_OP2_SHIFT))
>   
>   #define HSR_SYSREG_DCISW          HSR_SYSREG(1,0,c7,c6,2)
>   #define HSR_SYSREG_DCCSW          HSR_SYSREG(1,0,c7,c10,2)
--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxxx
https://lists.xenproject.org/mailman/listinfo/xen-devel