1 files changed, 94 insertions, 0 deletions
diff --git a/clang/test/SemaCXX/ms-uuid.cpp b/clang/test/SemaCXX/ms-uuid.cpp
new file mode 100644
index 00000000000..2192f67eabc
--- /dev/null
+++ b/clang/test/SemaCXX/ms-uuid.cpp
@@ -0,0 +1,94 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -fms-extensions %s
+
+typedef struct _GUID {
+  unsigned long Data1;
+  unsigned short Data2;
+  unsigned short Data3;
+  unsigned char Data4[8];
+} GUID;
+
+namespace {
+// cl.exe's behavior with merging uuid attributes is a bit erratic:
+// * In []-style attributes, a single [] list must not list a duplicate uuid
+//   (even if it's the same uuid), and only a single declaration of a class
+//   must have a uuid else the compiler errors out (even if two declarations of
+//   a class have the same uuid).
+// * For __declspec(uuid(...)), it's ok if several declarations of a class have
+//   an uuid, as long as it's the same uuid each time.  If uuids on declarations
+//   don't match, the compiler errors out.
+// * If there are several __declspec(uuid(...))s on one declaration, the
+//   compiler only warns about this and uses the last uuid.  It even warns if
+//   the uuids are the same.
+
+// clang-cl implements the following simpler (but largely compatible) behavior
+// instead:
+// * [] and __declspec uuids have the same behavior.
+// * If there are several uuids on a a class (no matter if on the same decl or
+//   on several decls), it is an error if they don't match.
+// * Having several uuids that match is ok.
+
+// Both cl and clang-cl accept this:
+class __declspec(uuid("000000A0-0000-0000-C000-000000000049")) C1;
+class __declspec(uuid("000000A0-0000-0000-C000-000000000049")) C1;
+class __declspec(uuid("000000A0-0000-0000-C000-000000000049")) C1 {};
+
+// Both cl and clang-cl error out on this:
+// expected-note@+1 2{{previous uuid specified here}}
+class __declspec(uuid("000000A0-0000-0000-C000-000000000049")) C2;
+// expected-error@+1 {{uuid does not match previous declaration}}
+class __declspec(uuid("110000A0-0000-0000-C000-000000000049")) C2;
+// expected-error@+1 {{uuid does not match previous declaration}}
+class __declspec(uuid("220000A0-0000-0000-C000-000000000049")) C2 {};
+
+// expected-note@+1 {{previous uuid specified here}}
+class __declspec(uuid("000000A0-0000-0000-C000-000000000049")) C2_2;
+class C2_2;
+// expected-error@+1 {{uuid does not match previous declaration}}
+class __declspec(uuid("110000A0-0000-0000-C000-000000000049")) C2_2;
+
+// clang-cl accepts this, but cl errors out:
+[uuid("000000A0-0000-0000-C000-000000000049")] class C3;
+[uuid("000000A0-0000-0000-C000-000000000049")] class C3;
+[uuid("000000A0-0000-0000-C000-000000000049")] class C3 {};
+
+// Both cl and clang-cl error out on this (but for different reasons):
+// expected-note@+1 2{{previous uuid specified here}}
+[uuid("000000A0-0000-0000-C000-000000000049")] class C4;
+// expected-error@+1 {{uuid does not match previous declaration}}
+[uuid("110000A0-0000-0000-C000-000000000049")] class C4;
+// expected-error@+1 {{uuid does not match previous declaration}}
+[uuid("220000A0-0000-0000-C000-000000000049")] class C4 {};
+
+// Both cl and clang-cl error out on this:
+// expected-note@+1 {{previous uuid specified here}}
+class __declspec(uuid("000000A0-0000-0000-C000-000000000049"))
+// expected-error@+1 {{uuid does not match previous declaration}}
+      __declspec(uuid("110000A0-0000-0000-C000-000000000049")) C5;
+
+// expected-note@+1 {{previous uuid specified here}}
+[uuid("000000A0-0000-0000-C000-000000000049"),
+// expected-error@+1 {{uuid does not match previous declaration}}
+ uuid("110000A0-0000-0000-C000-000000000049")] class C6;
+
+// cl doesn't diagnose having one uuid each as []-style attributes and as
+// __declspec, even if the uuids differ.  clang-cl errors if they differ.
+[uuid("000000A0-0000-0000-C000-000000000049")]
+class __declspec(uuid("000000A0-0000-0000-C000-000000000049")) C7;
+
+// expected-note@+1 {{previous uuid specified here}}
+[uuid("000000A0-0000-0000-C000-000000000049")]
+// expected-error@+1 {{uuid does not match previous declaration}}
+class __declspec(uuid("110000A0-0000-0000-C000-000000000049")) C8;
+
+
+// cl warns on this, but clang-cl is fine with it (which is consistent with
+// e.g. specifying __multiple_inheritance several times, which cl accepts
+// without warning too).
+class __declspec(uuid("000000A0-0000-0000-C000-000000000049"))
+      __declspec(uuid("000000A0-0000-0000-C000-000000000049")) C9;
+
+// cl errors out on this, but clang-cl is fine with it (to be consistent with
+// the previous case).
+[uuid("000000A0-0000-0000-C000-000000000049"),
+ uuid("000000A0-0000-0000-C000-000000000049")] class C10;
+}