diff --git a/hw/xfree86/drivers/video/ast/src/ast_mode.c b/hw/xfree86/drivers/video/ast/src/ast_mode.c
index 3485d50fec..dd549e01a0 100644
--- a/hw/xfree86/drivers/video/ast/src/ast_mode.c
+++ b/hw/xfree86/drivers/video/ast/src/ast_mode.c
@@ -491,7 +491,7 @@ Bool
 ASTSetMode(ScrnInfoPtr pScrn, DisplayModePtr mode)
 {
     ASTRecPtr pAST;
-    VBIOS_MODE_INFO vgamodeinfo;
+    VBIOS_MODE_INFO vgamodeinfo = { 0 };
 
     pAST = ASTPTR(pScrn);