1 files changed, 53 insertions, 0 deletions
diff --git a/test/CXX/basic/basic.link/p3.cpp b/test/CXX/basic/basic.link/p3.cpp
new file mode 100644
index 0000000000..23f39d11b6
--- /dev/null
+++ b/test/CXX/basic/basic.link/p3.cpp
@@ -0,0 +1,53 @@
+// RUN: %clang_cc1 -std=c++2a -verify %s
+// RUN: %clang_cc1 -std=c++2a -verify %s -DIMPORT_ERROR=1
+// RUN: %clang_cc1 -std=c++2a -verify %s -DIMPORT_ERROR=2
+
+module;
+
+#if IMPORT_ERROR != 2
+struct import { struct inner {}; };
+#endif
+struct module { struct inner {}; };
+
+constexpr int n = 123;
+
+export module m; // #1
+
+// Import errors are fatal, so we test them in isolation.
+#if IMPORT_ERROR == 1
+import x = {}; // expected-error {{module 'x' not found}}
+
+#elif IMPORT_ERROR == 2
+struct X;
+template<int> struct import;
+template<> struct import<n> {
+  static X y;
+};
+
+// This is not valid because the 'import <n>' is a pp-import, even though it
+// grammatically can't possibly be an import declaration.
+struct X {} import<n>::y; // expected-error {{'n' file not found}}
+
+#else
+module y = {}; // expected-error {{multiple module declarations}} expected-error 2{{}}
+// expected-note@#1 {{previous module declaration}}
+
+::import x = {};
+::module y = {};
+
+import::inner xi = {};
+module::inner yi = {};
+
+namespace N {
+  module a;
+  import b;
+}
+
+extern "C++" module cxxm;
+extern "C++" import cxxi;
+
+template<typename T> module module_var_template;
+
+// This is a variable named 'import' that shadows the type 'import' above.
+struct X {} import;
+#endif