diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index 56cb447..a86c9bd 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -1121,7 +1121,12 @@ fs_visitor::remove_dead_constants()
 	    if (inst->src[i].file != UNIFORM)
 	       continue;
 
-	    assert(constant_nr < (int)c->prog_data.nr_params);
+	    if (constant_nr >= (int)c->prog_data.nr_params) {
+	       ralloc_free(this->params_remap);
+	       this->params_remap = NULL;
+	       fail("accessed non-existent uniform");
+	       return false;
+	    }
 
 	    /* For now, set this to non-negative.  We'll give it the
 	     * actual new number in a moment, in order to keep the
diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
index 2dd212a..0593a1f 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
@@ -2270,6 +2270,8 @@ fs_visitor::fs_visitor(struct brw_wm_compile *c, struct gl_shader_program *prog,
    this->virtual_grf_use = NULL;
    this->live_intervals_valid = false;
 
+   this->params_remap = NULL;
+
    this->force_uncompressed_stack = 0;
    this->force_sechalf_stack = 0;
 }