[PATCH] randr: Silence valgrind after server regen with panning enabled

Chris Wilson chris at chris-wilson.co.uk
Fri Mar 16 04:39:32 PDT 2012

If when bug hunting you trigger a server regeneration after enabling a
pnning mode without moving the nice, you cause a flurry of valgrind

==28455== Conditional jump or move depends on uninitialised value(s)
==28455==    at 0x4D9431: xf86RandR13Pan (xf86RandR12.c:360)
==28455==    by 0x4DA4B1: xf86RandR12ScreenSetSize (xf86RandR12.c:725)
==28455==    by 0x4DA956: xf86RandR12CreateScreenResources
==28455==    by 0x4CB92B: xf86CrtcCreateScreenResources (xf86Crtc.c:728)
==28455==    by 0x425498: main (main.c:216)
==28455==  Uninitialised value was created by a heap allocation
==28455==    at 0x402894D: malloc (in
==28455==    by 0x4DAA74: xf86RandR12Init (xf86RandR12.c:889)
==28455==    by 0x4CBADD: xf86CrtcScreenInit (xf86Crtc.c:782)
==28455==    by 0xA71DBAE: I830ScreenInit (intel_driver.c:1034)
==28455==    by 0x43CE0E: AddScreen (dispatch.c:3909)
==28455==    by 0x48FDE6: InitOutput (xf86Init.c:817)
==28455==    by 0x425400: main (main.c:204)

Since these depend upon the user exiting without moving the mouse in an
unsual setup, the impact of this bug is going to be very small.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
 hw/xfree86/modes/xf86RandR12.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/hw/xfree86/modes/xf86RandR12.c b/hw/xfree86/modes/xf86RandR12.c
index d5031a2..b383197 100644
--- a/hw/xfree86/modes/xf86RandR12.c
+++ b/hw/xfree86/modes/xf86RandR12.c
@@ -909,6 +909,7 @@ xf86RandR12Init (ScreenPtr pScreen)
     randrp->supported_rotations = RR_Rotate_0;
     randrp->maxX = randrp->maxY = 0;
+    randrp->pointerX = randrp->pointerY = 0; /* keep valgrind quiet */
     dixSetPrivate(&pScreen->devPrivates, xf86RandR12Key, randrp);

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