[ms] Allow more unqualified lookup of types in dependent base classes

Summary:
In dependent contexts where we know a type name is required, such as a
new expression, we can recover by forming a DependentNameType.

This generalizes our existing compatibility hack for default arguments
for template type parameters.

Works towards parsing atlctrlw.h, which is PR26748.

Reviewers: avt77, rsmith

Subscribers: cfe-commits

Differential Revision: http://reviews.llvm.org/D20500

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@270615 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 31 insertions, 1 deletions

diff --git a/test/SemaTemplate/ms-lookup-template-base-classes.cpp b/test/SemaTemplate/ms-lookup-template-base-classes.cpp
index 4f3df277d9..51d19cef38 100644
--- a/test/SemaTemplate/ms-lookup-template-base-classes.cpp
+++ b/test/SemaTemplate/ms-lookup-template-base-classes.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -std=c++1y -fms-compatibility -fno-spell-checking -fsyntax-only -verify %s
+// RUN: %clang_cc1 -fcxx-exceptions -fexceptions -std=c++1y -fms-compatibility -fno-spell-checking -fsyntax-only -verify %s
 
 
 template <class T>
@@ -573,3 +573,33 @@ void h();
 template <typename T> decltype(h(T())) check2(); // expected-note{{candidate template ignored: substitution failure [with T = int]: no matching function for call to 'h'}}
 decltype(check2<int>()) y; // expected-error{{no matching function for call to 'check2'}}
 }
+
+// We also allow unqualified lookup into bases in contexts where the we know the
+// undeclared identifier *must* be a type, such as a new expression or catch
+// parameter type.
+template <typename T>
+struct UseUnqualifiedTypeNames : T {
+  void foo() {
+    void *P = new TheType; // expected-warning {{unqualified lookup}} expected-error {{no type}}
+    size_t x = __builtin_offsetof(TheType, f2); // expected-warning {{unqualified lookup}} expected-error {{no type}}
+    try {
+    } catch (TheType) { // expected-warning {{unqualified lookup}} expected-error {{no type}}
+    }
+    enum E : IntegerType { E0 = 42 }; // expected-warning {{unqualified lookup}} expected-error {{no type}}
+    _Atomic(TheType) a; // expected-warning {{unqualified lookup}} expected-error {{no type}}
+  }
+  void out_of_line();
+};
+template <typename T>
+void UseUnqualifiedTypeNames<T>::out_of_line() {
+  void *p = new TheType; // expected-warning {{unqualified lookup}} expected-error {{no type}}
+}
+struct Base {
+  typedef int IntegerType;
+  struct TheType {
+    int f1, f2;
+  };
+};
+template struct UseUnqualifiedTypeNames<Base>;
+struct BadBase { };
+template struct UseUnqualifiedTypeNames<BadBase>; // expected-note-re 2 {{in instantiation {{.*}} requested here}}