i965: Fix a potential assertion failure.

diff --git a/src/mesa/drivers/dri/i965/brw_draw_upload.c b/src/mesa/drivers/dri/i965/brw_draw_upload.c
index 303eaac5cf9e36a885a8be3a4be89e6033d612b9..cc3d9396acd8b2c5eb7c41adc2d8f0c0bd3ec077 100644 (file)
--- a/src/mesa/drivers/dri/i965/brw_draw_upload.c
+++ b/src/mesa/drivers/dri/i965/brw_draw_upload.c
@@ -365,8 +365,10 @@ static void brw_prepare_vertices(struct brw_context *brw)
         if (i == 0) {
            /* Position array not properly enabled:
             */
-           if (input->glarray->StrideB == 0)
-             return;
+            if (input->glarray->StrideB == 0) {
+               intel->Fallback = 1;
+               return;
+            }
 
            interleave = input->glarray->StrideB;
            ptr = input->glarray->Ptr;