diff --git a/src/compiler/glsl/glsl_to_nir.cpp b/src/compiler/glsl/glsl_to_nir.cpp
index 50c02e34e77..8c96e914387 100644
--- a/src/compiler/glsl/glsl_to_nir.cpp
+++ b/src/compiler/glsl/glsl_to_nir.cpp
@@ -486,6 +486,9 @@ get_nir_how_declared(unsigned how_declared)
    if (how_declared == ir_var_hidden)
       return nir_var_hidden;
 
+   if (how_declared == ir_var_declared_implicitly)
+      return nir_var_declared_implicitly;
+
    return nir_var_declared_normally;
 }
 
diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h
index 3e5188611de..a96e9b78567 100644
--- a/src/compiler/nir/nir.h
+++ b/src/compiler/nir/nir.h
@@ -430,6 +430,12 @@ typedef enum {
     */
    nir_var_declared_normally = 0,
 
+   /**
+    * Variable is an implicitly declared built-in that has not been explicitly
+    * re-declared by the shader.
+    */
+   nir_var_declared_implicitly,
+
    /**
     * Variable is implicitly generated by the compiler and should not be
     * visible via the API.