diff --git a/mlir/lib/Dialect/StandardOps/IR/Ops.cpp b/mlir/lib/Dialect/StandardOps/IR/Ops.cpp
--- a/mlir/lib/Dialect/StandardOps/IR/Ops.cpp
+++ b/mlir/lib/Dialect/StandardOps/IR/Ops.cpp
@@ -1120,7 +1120,8 @@
     auto fn =
         op.getParentOfType<ModuleOp>().lookupSymbol<FuncOp>(fnAttr.getValue());
     if (!fn)
-      return op.emitOpError("reference to undefined function 'bar'");
+      return op.emitOpError()
+             << "reference to undefined function '" << fnAttr.getValue() << "'";
 
     // Check that the referenced function has the correct type.
     if (fn.getType() != type)
diff --git a/mlir/test/IR/invalid.mlir b/mlir/test/IR/invalid.mlir
--- a/mlir/test/IR/invalid.mlir
+++ b/mlir/test/IR/invalid.mlir
@@ -513,7 +513,7 @@
 
 func @undefined_function() {
 ^bb0:
-  %x = constant @bar : (i32) -> ()  // expected-error {{reference to undefined function 'bar'}}
+  %x = constant @qux : (i32) -> ()  // expected-error {{reference to undefined function 'qux'}}
   return
 }