Re: [PATCH] KVM: arm64: Avoid shadowing a previous local
From: Marc Zyngier
Date: Wed Oct 27 2021 - 03:34:45 EST
On 2021-10-27 03:42, Qian Cai wrote:
It is less-prone to have a different variable name from the one in a
wider
scope. This is also flagged by GCC (W=2):
In file included from ./include/linux/kvm_host.h:39,
from arch/arm64/kvm/arm.c:12:
arch/arm64/kvm/arm.c: In function 'kvm_arch_vcpu_ioctl_run':
./arch/arm64/include/asm/kvm_host.h:638:26: warning: declaration of
'ret' shadows a previous local [-Wshadow]
638 | typeof(f(__VA_ARGS__)) ret; \
| ^~~
arch/arm64/kvm/arm.c:852:9: note: in expansion of macro
'kvm_call_hyp_ret'
852 | ret = kvm_call_hyp_ret(__kvm_vcpu_run, vcpu);
| ^~~~~~~~~~~~~~~~
arch/arm64/kvm/arm.c:773:6: note: shadowed declaration is here
773 | int ret;
| ^~~
Signed-off-by: Qian Cai <quic_qiancai@xxxxxxxxxxx>
---
arch/arm64/include/asm/kvm_host.h | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/include/asm/kvm_host.h
b/arch/arm64/include/asm/kvm_host.h
index 4be8486042a7..4693d84ccd95 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -635,16 +635,16 @@ void kvm_arm_resume_guest(struct kvm *kvm);
#define kvm_call_hyp_ret(f, ...) \
({ \
- typeof(f(__VA_ARGS__)) ret; \
+ typeof(f(__VA_ARGS__)) __ret; \
\
if (has_vhe()) { \
- ret = f(__VA_ARGS__); \
+ __ret = f(__VA_ARGS__); \
isb(); \
} else { \
- ret = kvm_call_hyp_nvhe(f, ##__VA_ARGS__); \
+ __ret = kvm_call_hyp_nvhe(f, ##__VA_ARGS__); \
} \
\
- ret; \
+ __ret; \
})
#else /* __KVM_NVHE_HYPERVISOR__ */
#define kvm_call_hyp(f, ...) f(__VA_ARGS__)
I don't think this makes much sense. This is bound to eventually clash
with another variable, and you're back to square one.
Thanks,
M.
--
Jazz is not dead. It just smells funny...