Building QEMU on fedora26 with the latest gcc package fails:
CC ppc64-softmmu/target/ppc/kvm.o
In file included from include/sysemu/hw_accel.h:16:0,
from target/ppc/kvm.c:31:
target/ppc/kvm.c: In function ‘kvmppc_booke_watchdog_enable’:
include/sysemu/kvm.h:449:35: error: ‘args_tmp[i]’ may be used uninitialized
in this function [-Werror=maybe-uninitialized]
cap.args[i] = args_tmp[i]; \
^
target/ppc/kvm.c: In function ‘kvmppc_set_papr’:
include/sysemu/kvm.h:449:35: error: ‘args_tmp[i]’ may be used uninitialized
in this function [-Werror=maybe-uninitialized]
cc1: all warnings being treated as errors
$ rpm -q gcc
gcc-7.1.1-3.fc26.ppc64le
Testing the size of args_tmp seems to be enough to prevent the warning
to pop up.
Signed-off-by: Greg Kurz <gr...@kaod.org>
---
include/sysemu/kvm.h | 12 ++++++++----
1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/include/sysemu/kvm.h b/include/sysemu/kvm.h
index 91fc07ee9afe..41fc1005a9ea 100644
--- a/include/sysemu/kvm.h
+++ b/include/sysemu/kvm.h
@@ -429,9 +429,11 @@ int kvm_vm_check_extension(KVMState *s, unsigned int
extension);
}; \
uint64_t args_tmp[] = { __VA_ARGS__ }; \
int i; \
- for (i = 0; i < (int)ARRAY_SIZE(args_tmp) && \
+ if (sizeof(args_tmp)) { \
+ for (i = 0; i < (int)ARRAY_SIZE(args_tmp) && \
i < ARRAY_SIZE(cap.args); i++) { \
- cap.args[i] = args_tmp[i]; \
+ cap.args[i] = args_tmp[i]; \
+ } \
} \
kvm_vm_ioctl(s, KVM_ENABLE_CAP, &cap); \
})
@@ -444,9 +446,11 @@ int kvm_vm_check_extension(KVMState *s, unsigned int
extension);
}; \
uint64_t args_tmp[] = { __VA_ARGS__ }; \
int i; \
- for (i = 0; i < (int)ARRAY_SIZE(args_tmp) && \
+ if (sizeof(args_tmp)) { \
+ for (i = 0; i < (int)ARRAY_SIZE(args_tmp) && \
i < ARRAY_SIZE(cap.args); i++) { \
- cap.args[i] = args_tmp[i]; \
+ cap.args[i] = args_tmp[i]; \
+ } \
} \
kvm_vcpu_ioctl(cpu, KVM_ENABLE_CAP, &cap); \
})
