On Thu, Jan 06, 2011 at 07:45:01PM +0000, Blue Swirl wrote:
> There are a few variables which appear uninitialized to GCC 4.6.0:
It's due to my commit 92d675d1c1f23f3617e24b63c825074a1d1da44b
> CC i386-softmmu/cirrus_vga.o
> /src/qemu/hw/cirrus_vga.c: In function 'cirrus_bitblt_start':
> /src/qemu/hw/cirrus_vga.c:678: warning: 'depth' may be used
> uninitialized in this function
> /src/qemu/hw/cirrus_vga.c:678: note: 'depth' was declared here
> /src/qemu/hw/cirrus_vga.c:677: warning: 'dx' may be used uninitialized
> in this function
> /src/qemu/hw/cirrus_vga.c:677: note: 'dx' was declared here
> /src/qemu/hw/cirrus_vga.c:676: warning: 'sx' may be used uninitialized
> in this function
> /src/qemu/hw/cirrus_vga.c:676: note: 'sx' was declared here
> /src/qemu/hw/cirrus_vga.c:676: warning: 'sy' may be used uninitialized
> in this function
> /src/qemu/hw/cirrus_vga.c:676: note: 'sy' was declared here
> /src/qemu/hw/cirrus_vga.c:677: warning: 'dy' may be used uninitialized
> in this function
> /src/qemu/hw/cirrus_vga.c:677: note: 'dy' was declared here
>
> I don't think they are, since the variable use is conditional to
> notify variable:
> if (notify)
> qemu_console_copy(s->vga.ds,
> sx, sy, dx, dy,
> s->cirrus_blt_width / depth,
> s->cirrus_blt_height);
Strangely neither GCC 4.4 nor GCC 4.5 trigger such a warning, though
they are usually catching cases like that. Could it be a regression in
GCC 4.6, or do you think it's just that it wasn't detected in previous
versions?
> Perhaps the code could be rearranged to avoid the warnings? Otherwise
> we could add zero initializers.
>
Rearranging the code doesn't seems easy, so we should probably go to
zero initializers, as in the patch below.
From: Aurelien Jarno <aurel...@aurel32.net>
cirrus: delete GCC 4.6 warnings
Commit 92d675d1c1f23f3617e24b63c825074a1d1da44b triggered uninitialized
variables warning with GCC 4.6. Fix them by adding zero initializers.
Signed-off-by: Aurelien Jarno <aurel...@aurel32.net>
---
hw/cirrus_vga.c | 6 +++---
1 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/hw/cirrus_vga.c b/hw/cirrus_vga.c
index 833a2eb..75d1cc6 100644
--- a/hw/cirrus_vga.c
+++ b/hw/cirrus_vga.c
@@ -673,9 +673,9 @@ static int
cirrus_bitblt_videotovideo_patterncopy(CirrusVGAState * s)
static void cirrus_do_copy(CirrusVGAState *s, int dst, int src, int w, int h)
{
- int sx, sy;
- int dx, dy;
- int depth;
+ int sx = 0, sy = 0;
+ int dx = 0, dy = 0;
+ int depth = 0;
int notify = 0;
/* make sure to only copy if it's a plain copy ROP */
--
Aurelien Jarno GPG: 1024D/F1BCDB73
aurel...@aurel32.net http://www.aurel32.net
