diff --git a/src/glsl/ast.h b/src/glsl/ast.h
index 87f987682cd..8abea5225f0 100644
--- a/src/glsl/ast.h
+++ b/src/glsl/ast.h
@@ -460,7 +460,8 @@ public:
     * be modified. Zeros the inherited ast_node's fields.
     */
    ast_struct_specifier(const ast_struct_specifier& that):
-      ast_node(), name(that.name), declarations(that.declarations)
+      ast_node(), name(that.name), declarations(that.declarations),
+      is_declaration(that.is_declaration)
    {
       /* empty */
    }
@@ -475,6 +476,7 @@ public:
    const char *name;
    /* List of ast_declarator_list * */
    exec_list declarations;
+   bool is_declaration;
 };
 
 
diff --git a/src/glsl/glsl_parser_extras.cpp b/src/glsl/glsl_parser_extras.cpp
index 664f8d15917..aa5a435fa95 100644
--- a/src/glsl/glsl_parser_extras.cpp
+++ b/src/glsl/glsl_parser_extras.cpp
@@ -1236,6 +1236,7 @@ ast_struct_specifier::ast_struct_specifier(const char *identifier,
    }
    name = identifier;
    this->declarations.push_degenerate_list_at_head(&declarator_list->link);
+   is_declaration = true;
 }
 
 extern "C" {