Fix the mangling of function pointers in the MS ABI.
Patch by Timur Iskhodzhanov!

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@162638 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/MicrosoftMangle.cpp b/lib/AST/MicrosoftMangle.cpp
index e2cee7f..7263190 100644
--- a/lib/AST/MicrosoftMangle.cpp
+++ b/lib/AST/MicrosoftMangle.cpp
@@ -1059,6 +1059,8 @@
                                          SourceRange) {
   // Structors only appear in decls, so at this point we know it's not a
   // structor type.
+  // FIXME: This may not be lambda-friendly.
+  Out << "$$A6";
   mangleType(T, NULL, false, false);
 }
 void MicrosoftCXXNameMangler::mangleType(const FunctionNoProtoType *T,
@@ -1214,7 +1216,7 @@
   if (CC == CC_Default) {
     if (IsInstMethod) {
       const FunctionProtoType *FPT =
-        T->getCanonicalTypeUnqualified().getAs<FunctionProtoType>();
+        T->getCanonicalTypeUnqualified().castAs<FunctionProtoType>();
       bool isVariadic = FPT->isVariadic();
       CC = getASTContext().getDefaultCXXMethodCallConv(isVariadic);
     } else {
@@ -1497,7 +1499,9 @@
 void MicrosoftCXXNameMangler::mangleType(const BlockPointerType *T,
                                          SourceRange Range) {
   Out << "_E";
-  mangleType(T->getPointeeType(), Range);
+
+  QualType pointee = T->getPointeeType();
+  mangleType(pointee->castAs<FunctionProtoType>(), NULL, false, false);
 }
 
 void MicrosoftCXXNameMangler::mangleType(const InjectedClassNameType *T,
diff --git a/test/CodeGenCXX/mangle-ms-template-callback.cpp b/test/CodeGenCXX/mangle-ms-template-callback.cpp
new file mode 100644
index 0000000..6878148
--- /dev/null
+++ b/test/CodeGenCXX/mangle-ms-template-callback.cpp
@@ -0,0 +1,72 @@
+// RUN: %clang_cc1 -fblocks -emit-llvm %s -o - -cxx-abi microsoft -triple=i386-pc-win32 | FileCheck %s
+
+template<typename Signature>
+class C;
+
+template<typename Ret>
+class C<Ret(void)> {};
+typedef C<void(void)> C0;
+
+template<typename Ret, typename Arg1>
+class C<Ret(Arg1)> {};
+
+template<typename Ret, typename Arg1, typename Arg2>
+class C<Ret(Arg1, Arg2)> {};
+
+C0 callback_void;
+// CHECK: "\01?callback_void@@3V?$C@$$A6AXXZ@@A"
+
+volatile C0 callback_void_volatile;
+// CHECK: "\01?callback_void_volatile@@3V?$C@$$A6AXXZ@@C"
+
+class Type {};
+
+C<int(void)> callback_int;
+// CHECK: "\01?callback_int@@3V?$C@$$A6AHXZ@@A"
+C<Type(void)> callback_Type;
+// CHECK: "\01?callback_Type@@3V?$C@$$A6A?AVType@@XZ@@A"
+
+C<void(int)> callback_void_int;
+// CHECK: "\01?callback_void_int@@3V?$C@$$A6AXH@Z@@A"
+C<int(int)> callback_int_int;
+// CHECK: "\01?callback_int_int@@3V?$C@$$A6AHH@Z@@A"
+C<void(Type)> callback_void_Type;
+// CHECK: "\01?callback_void_Type@@3V?$C@$$A6AXVType@@@Z@@A"
+
+void foo(C0 c) {}
+// CHECK: "\01?foo@@YAXV?$C@$$A6AXXZ@@@Z"
+
+// Here be dragons!
+// Let's face the magic of template partial specialization...
+
+void function(C<void(void)>) {}
+// CHECK: "\01?function@@YAXV?$C@$$A6AXXZ@@@Z"
+
+template<typename Ret> class C<Ret(*)(void)> {};
+void function_pointer(C<void(*)(void)>) {}
+// CHECK: "\01?function_pointer@@YAXV?$C@P6AXXZ@@@Z"
+
+// Block equivalent to the previous definitions.
+template<typename Ret> class C<Ret(^)(void)> {};
+void block(C<void(^)(void)>) {}
+// CHECK: "\01?block@@YAXV?$C@P_EAXXZ@@@Z"
+// FYI blocks are not present in MSVS, so we're free to choose the spec.
+
+template<typename T> class C<void (T::*)(void)> {};
+class Z {
+ public:
+  void method() {}
+};
+void member_pointer(C<void (Z::*)(void)>) {}
+// CHECK: "\01?member_pointer@@YAXV?$C@P8Z@@AEXXZ@@@Z"
+
+template<typename T> void bar(T) {}
+
+void call_bar() {
+  bar<int (*)(int)>(0);
+// CHECK: "\01??$bar@P6AHH@Z@@YAXP6AHH@Z@Z"
+
+  bar<int (^)(int)>(0);
+// CHECK: "\01??$bar@P_EAHH@Z@@YAXP_EAHH@Z@Z"
+// FYI blocks are not present in MSVS, so we're free to choose the spec.
+}
diff --git a/test/CodeGenCXX/mangle-ms.cpp b/test/CodeGenCXX/mangle-ms.cpp
index f392c17..ef210f5 100644
--- a/test/CodeGenCXX/mangle-ms.cpp
+++ b/test/CodeGenCXX/mangle-ms.cpp
@@ -128,6 +128,10 @@
 void eta(int (^)(int, int)) {}
 // CHECK: @"\01?eta@@YAXP_EAHHH@Z@Z"
 
+typedef int theta_arg(int,int);
+void theta(theta_arg^ block) {}
+// CHECK: @"\01?theta@@YAXP_EAHHH@Z@Z"
+
 void operator_new_delete() {
   char *ptr = new char;
 // CHECK: @"\01??2@YAPAXI@Z"