i965: added null const_buffer pointer check in update_constant_buffer()

diff --git a/src/mesa/drivers/dri/i965/brw_curbe.c b/src/mesa/drivers/dri/i965/brw_curbe.c
index 08b602a..94bf2c0 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_curbe.c
+++ b/src/mesa/drivers/dri/i965/brw_curbe.c
@@ -343,7 +343,7 @@ update_constant_buffer(struct brw_context *brw,
    const int size = params->NumParameters * 4 * sizeof(GLfloat);
 
    /* copy Mesa program constants into the buffer */
-   if (size > 0) {
+   if (const_buffer && size > 0) {
       GLubyte *map;
 
       assert(const_buffer);