Declaring variables of type works

core_codegen_c_language.cpp

@@ -114,6 +114,7 @@ string_simple_decl_prefix(Ast_Type *ast) {
             String string = pctx->fmt("Tuple%llu ", ast->type_id);
             return string;
         } break;
+        case TYPE_UNION:
         case TYPE_STRUCT: {
             auto constant = (Ast_Decl *)ast->ast;
             auto name = constant->unique_name;