Fix the __interface inheritence rules to work better with IUnknown and IDispatch

__interface objects in MSVC are permitted to inherit from __interface types, 
and interface-like types.

Additionally, there are two default interface-like types 
(IUnknown and IDispatch) that all interface-like
types must inherit from.

Differential Revision: https://reviews.llvm.org/D37308

llvm-svn: 313364

1 files changed, 39 insertions, 0 deletions

diff --git a/clang/test/SemaCXX/ms-iunknown.cpp b/clang/test/SemaCXX/ms-iunknown.cpp
new file mode 100644
index 00000000000..c965a4c0a1b
--- /dev/null
+++ b/clang/test/SemaCXX/ms-iunknown.cpp
@@ -0,0 +1,39 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -fms-extensions %s 
+
+struct __declspec(uuid("00000000-0000-0000-C000-000000000046")) IUnknown {
+  void foo();
+};
+struct IPropertyPageBase : public IUnknown {};
+struct IPropertyPage : public IPropertyPageBase {};
+__interface ISfFileIOPropertyPage : public IPropertyPage {};
+
+
+namespace NS {
+  struct __declspec(uuid("00000000-0000-0000-C000-000000000046")) IUnknown {};
+  // expected-error@+1 {{interface type cannot inherit from}}
+  __interface IPropertyPageBase : public IUnknown {}; 
+}
+// expected-error@+1 {{interface type cannot inherit from}}
+__interface IPropertyPageBase2 : public NS::IUnknown {}; 
+
+__interface temp_iface {};
+struct bad_base : temp_iface {};
+// expected-error@+1 {{interface type cannot inherit from}}
+__interface bad_inherit : public bad_base{};
+
+struct mult_inher_base : temp_iface, IUnknown {};
+// expected-error@+1 {{interface type cannot inherit from}}
+__interface bad_inherit2 : public mult_inher_base{};
+
+struct PageBase : public IUnknown {};
+struct Page3 : public PageBase {};
+struct Page4 : public PageBase {};
+__interface PropertyPage : public Page4 {};
+
+struct Page5 : public Page3, Page4{};
+// expected-error@+1 {{interface type cannot inherit from}}
+__interface PropertyPage2 : public Page5 {}; 
+
+__interface IF1 {};
+__interface PP : IUnknown, IF1{}; 
+__interface PP2 : PP, Page3, Page4{};