diff --git a/src/compiler/glsl/ir.h b/src/compiler/glsl/ir.h
index 4dc2a5f6bc7..6f7b4542b1d 100644
--- a/src/compiler/glsl/ir.h
+++ b/src/compiler/glsl/ir.h
@@ -233,7 +233,7 @@ public:
 
    ir_rvalue *as_rvalue_to_saturate();
 
-   virtual bool is_lvalue(const struct _mesa_glsl_parse_state *state = NULL) const
+   virtual bool is_lvalue(const struct _mesa_glsl_parse_state * = NULL) const
    {
       return false;
    }