diff --git a/clang/test/Modules/Inputs/gnumode-non-benign/module.h b/clang/test/Modules/Inputs/gnumode-non-benign/module.h
new file mode 100644
index 000000000000..efde0ad70c55
--- /dev/null
+++ b/clang/test/Modules/Inputs/gnumode-non-benign/module.h
@@ -0,0 +1,5 @@
+// Check for GNUMode = 1 by looking for the "linux" define which only exists
+// for GNUMode = 1.
+#ifdef linux
+ #error "Submodule has GNUMode=1"
+#endif
diff --git a/clang/test/Modules/Inputs/gnumode-non-benign/module.modulemap b/clang/test/Modules/Inputs/gnumode-non-benign/module.modulemap
new file mode 100644
index 000000000000..702ef596eb06
--- /dev/null
+++ b/clang/test/Modules/Inputs/gnumode-non-benign/module.modulemap
@@ -0,0 +1 @@
+module "module.h" { header "module.h"}
diff --git a/clang/test/Modules/gnumode-non-benign.cpp b/clang/test/Modules/gnumode-non-benign.cpp
new file mode 100644
index 000000000000..9255dfe24b11
--- /dev/null
+++ b/clang/test/Modules/gnumode-non-benign.cpp
@@ -0,0 +1,11 @@
+// RUN: rm -rf %t
+// RUN: %clang_cc1 -std=c++11 -fmodules -fimplicit-module-maps -fmodules-cache-path=%t -I%S/Inputs/gnumode-non-benign -verify %s
+
+// expected-no-diagnostics
+
+// This test ensures that submodules have the same GNUMode language option
+// setting as the main clang invocation.
+// Note that we set GNUMode = 0 with -std=c++11 for this file.
+
+// This module fails to compile with GNUMode = 1.
+#include "module.h"