4 files changed, 28 insertions, 0 deletions
diff --git a/clang/test/Modules/Inputs/Modified/A.h b/clang/test/Modules/Inputs/Modified/A.h
new file mode 100644
index 00000000000..ff833c7520f
--- /dev/null
+++ b/clang/test/Modules/Inputs/Modified/A.h
@@ -0,0 +1 @@
+int getA();
diff --git a/clang/test/Modules/Inputs/Modified/B.h b/clang/test/Modules/Inputs/Modified/B.h
new file mode 100644
index 00000000000..d1c8bb5e8e1
--- /dev/null
+++ b/clang/test/Modules/Inputs/Modified/B.h
@@ -0,0 +1,2 @@
+#include "A.h"
+int getB();
diff --git a/clang/test/Modules/Inputs/Modified/module.map b/clang/test/Modules/Inputs/Modified/module.map
new file mode 100644
index 00000000000..d9aed01430c
--- /dev/null
+++ b/clang/test/Modules/Inputs/Modified/module.map
@@ -0,0 +1,2 @@
+module A { header "A.h" }
+module B { header "B.h" }
diff --git a/clang/test/Modules/modify-module.m b/clang/test/Modules/modify-module.m
new file mode 100644
index 00000000000..b630ac10587
--- /dev/null
+++ b/clang/test/Modules/modify-module.m
@@ -0,0 +1,23 @@
+// Test that if we modify one of the input files used to form a
+// header, that module and dependent modules get rebuilt.
+
+// RUN: rm -rf %t
+// RUN: mkdir -p %t/include
+// RUN: cp %S/Inputs/Modified/A.h %t/include
+// RUN: cp %S/Inputs/Modified/B.h %t/include
+// RUN: cp %S/Inputs/Modified/module.map %t/include
+// RUN: %clang_cc1 -fmodule-cache-path %t/cache -fmodules -I %t/include %s -verify
+// expected-no-diagnostics
+// RUN: touch %t/include/B.h
+// RUN: %clang_cc1 -fmodule-cache-path %t/cache -fmodules -I %t/include %s -verify
+// RUN: echo 'int getA(); int getA2();' > %t/include/A.h
+// RUN: %clang_cc1 -fmodule-cache-path %t/cache -fmodules -I %t/include %s -verify
+
+@__experimental_modules_import B;
+
+int getValue() { return getA() + getB(); }
+
+
+
+
+