Mesa (master): i915g: Handle null constants properly

[Jakob Bornecrantz]

Module: Mesa
Branch: master
Commit: 052122a8cd759e8749fee3412bae5d905ee0d965
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=052122a8cd759e8749fee3412bae5d905ee0d965

Author: Jakob Bornecrantz <wallbraker at gmail.com>
Date:   Sat Feb 26 15:45:13 2011 +0100

i915g: Handle null constants properly

---

 src/gallium/drivers/i915/i915_context.c |    9 ++++++---
 1 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/gallium/drivers/i915/i915_context.c b/src/gallium/drivers/i915/i915_context.c
index 707b2e9..f970f8a 100644
--- a/src/gallium/drivers/i915/i915_context.c
+++ b/src/gallium/drivers/i915/i915_context.c
@@ -73,10 +73,13 @@ i915_draw_vbo(struct pipe_context *pipe, const struct pipe_draw_info *info)
    draw_set_mapped_index_buffer(draw, mapped_indices);
 
    if (cbuf_dirty) {
-      draw_set_mapped_constant_buffer(draw, PIPE_SHADER_VERTEX, 0,
-                                      i915_buffer(i915->constants[PIPE_SHADER_VERTEX])->data,
-                                      (i915->current.num_user_constants[PIPE_SHADER_VERTEX] * 
+      if (i915->constants[PIPE_SHADER_VERTEX])
+         draw_set_mapped_constant_buffer(draw, PIPE_SHADER_VERTEX, 0,
+                                         i915_buffer(i915->constants[PIPE_SHADER_VERTEX])->data,
+                                         (i915->current.num_user_constants[PIPE_SHADER_VERTEX] * 
                                          4 * sizeof(float)));
+      else
+         draw_set_mapped_constant_buffer(draw, PIPE_SHADER_VERTEX, 0, NULL, 0);
    }
 
    /*