diff --git a/src/glsl/nir/nir.h b/src/glsl/nir/nir.h
index dbd73f15b22..f2794cb7afb 100644
--- a/src/glsl/nir/nir.h
+++ b/src/glsl/nir/nir.h
@@ -874,7 +874,7 @@ typedef struct {
     */
    uint8_t num_components;
 
-   int const_index[3];
+   int const_index[4];
 
    nir_deref_var *variables[2];