From: Eric Anholt <eric@anholt.net>
Date: Fri, 20 Nov 2009 20:42:06 +0000 (+0100)
Subject: mesa: Fix NULL deref in optimizer when NumInstructions == 0.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=c4e8918cd248189d43cdc8df9f9f0450040261c5;p=mesa.git

mesa: Fix NULL deref in optimizer when NumInstructions == 0.

Bug #24984.
---

diff --git a/src/mesa/shader/prog_optimize.c b/src/mesa/shader/prog_optimize.c
index 3d28d885a44..4fe351251e8 100644
--- a/src/mesa/shader/prog_optimize.c
+++ b/src/mesa/shader/prog_optimize.c
@@ -443,7 +443,7 @@ _mesa_remove_extra_move_use(struct gl_program *prog)
     *    FOO tmpY, arg0, arg1;
     */
 
-   for (i = 0; i < prog->NumInstructions - 1; i++) {
+   for (i = 0; i + 1 < prog->NumInstructions; i++) {
       const struct prog_instruction *mov = prog->Instructions + i;
 
       if (mov->Opcode != OPCODE_MOV ||