Patchwork compiler: fix warning with GCC 4.8.0

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Submitter Paolo Bonzini
Date March 27, 2013, 1:34 p.m.
Message ID <1364391272-1128-1-git-send-email-pbonzini@redhat.com>
Download mbox | patch
Permalink /patch/231689/
State New
Headers show

Comments

Paolo Bonzini - March 27, 2013, 1:34 p.m.
GCC 4.8.0 introduces a new warning:

    block/qcow2-snapshot.c: In function 'qcow2_write_snapshots’:
    block/qcow2-snapshot.c:252:18: error: typedef 'qemu_build_bug_on__253'
              locally defined but not used [-Werror=unused-local-typedefs]
         QEMU_BUILD_BUG_ON(offsetof(QCowHeader, snapshots_offset) !=
                  ^
    cc1: all warnings being treated as errors

(Caret diagnostics aren't perfect yet with macros... :)) Work around it
with __attribute__((unused)).

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 include/qemu/compiler.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
Richard Henderson - March 27, 2013, 8:33 p.m.
On 03/27/2013 06:34 AM, Paolo Bonzini wrote:
> GCC 4.8.0 introduces a new warning:
> 
>     block/qcow2-snapshot.c: In function 'qcow2_write_snapshots’:
>     block/qcow2-snapshot.c:252:18: error: typedef 'qemu_build_bug_on__253'
>               locally defined but not used [-Werror=unused-local-typedefs]
>          QEMU_BUILD_BUG_ON(offsetof(QCowHeader, snapshots_offset) !=
>                   ^
>     cc1: all warnings being treated as errors
> 
> (Caret diagnostics aren't perfect yet with macros... :)) Work around it
> with __attribute__((unused)).
> 
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Reviewed-by: Richard Henderson <rth@twiddle.net>

Thanks, I've just been adding -Wno-unused-local-typedefs locally for a bit.


r~
Anthony Liguori - March 27, 2013, 9:15 p.m.
Applied.  Thanks.

Regards,

Anthony Liguori

Patch

diff --git a/include/qemu/compiler.h b/include/qemu/compiler.h
index 2f7998b..6175c24 100644
--- a/include/qemu/compiler.h
+++ b/include/qemu/compiler.h
@@ -33,7 +33,7 @@ 
 #define cat(x,y) x ## y
 #define cat2(x,y) cat(x,y)
 #define QEMU_BUILD_BUG_ON(x) \
-    typedef char cat2(qemu_build_bug_on__,__LINE__)[(x)?-1:1];
+    typedef char cat2(qemu_build_bug_on__,__LINE__)[(x)?-1:1] __attribute__((unused));
 
 #if defined __GNUC__
 # if !QEMU_GNUC_PREREQ(4, 4)