PR13433: In Microsoft mode, don't require function calls within decltype

expressions to have complete return types (or accessible destructors). If the
return type is required to be complete for some other reason (for instance, if
it is needed by overload resolution), then it will still be required to be
complete. This is apparently required in order to parse a MSVC11 header.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@160924 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 19 insertions, 0 deletions

diff --git a/lib/Sema/SemaExprCXX.cpp b/lib/Sema/SemaExprCXX.cpp
index 278549b4b7..b47bd970d0 100644
--- a/lib/Sema/SemaExprCXX.cpp
+++ b/lib/Sema/SemaExprCXX.cpp
@@ -4783,6 +4783,11 @@ ExprResult Sema::ActOnDecltypeExpression(Expr *E) {
   // Disable the special decltype handling now.
   Rec.IsDecltype = false;
 
+  // In MS mode, don't perform any extra checking of call return types within a
+  // decltype expression.
+  if (getLangOpts().MicrosoftMode)
+    return Owned(E);
+
   // Perform the semantic checks we delayed until this point.
   CallExpr *TopCall = dyn_cast<CallExpr>(E);
   for (unsigned I = 0, N = Rec.DelayedDecltypeCalls.size(); I != N; ++I) {
diff --git a/test/SemaCXX/microsoft-cxx0x.cpp b/test/SemaCXX/microsoft-cxx0x.cpp
index 3b9bbefc0c..79bd7c39e5 100644
--- a/test/SemaCXX/microsoft-cxx0x.cpp
+++ b/test/SemaCXX/microsoft-cxx0x.cpp
@@ -1,4 +1,5 @@
 // RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -Wc++11-narrowing -Wmicrosoft -verify -fms-extensions -std=c++11
+// RUN: %clang_cc1 %s -triple i686-pc-win32 -fsyntax-only -Wc++11-narrowing -Wmicrosoft -verify -fms-extensions -std=c++11 -fms-compatibility -DMS_COMPAT
 
 
 struct A {
@@ -6,3 +7,16 @@ struct A {
 };
 int b = 3;
 A var = {  b }; // expected-warning {{ cannot be narrowed }} expected-note {{override}}
+
+
+namespace PR13433 {
+  struct S;
+  S make();
+
+  template<typename F> auto x(F f) -> decltype(f(make()));
+#ifndef MS_COMPAT
+// expected-error@-2{{calling 'make' with incomplete return type 'PR13433::S'}}
+// expected-note@-5{{'make' declared here}}
+// expected-note@-7{{forward declaration of 'PR13433::S'}}
+#endif
+}