In objective-c++ land, a block pointer is another object pointer.

So, casting a generic object pointer ('id' or 'Class') to the
block pointer is allowed. Fixes radar 7562285.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@94045 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 32 insertions, 1 deletions

diff --git a/lib/Sema/SemaOverload.cpp b/lib/Sema/SemaOverload.cpp
index 3b6cf89306..e9b6072adc 100644
--- a/lib/Sema/SemaOverload.cpp
+++ b/lib/Sema/SemaOverload.cpp
@@ -1141,8 +1141,16 @@ bool Sema::isObjCPointerConversion(QualType FromType, QualType ToType,
   QualType ToPointeeType;
   if (const PointerType *ToCPtr = ToType->getAs<PointerType>())
     ToPointeeType = ToCPtr->getPointeeType();
-  else if (const BlockPointerType *ToBlockPtr = ToType->getAs<BlockPointerType>())
+  else if (const BlockPointerType *ToBlockPtr = 
+            ToType->getAs<BlockPointerType>()) {
+    // Objective C++: We're able to convert from a pointer to an any object
+    // to a block pointer type.
+    if (FromObjCPtr && FromObjCPtr->isObjCBuiltinType()) {
+      ConvertedType = ToType;
+      return true;
+    }
     ToPointeeType = ToBlockPtr->getPointeeType();
+  }
   else
     return false;
 
diff --git a/test/SemaObjCXX/cstyle-block-pointer-cast.mm b/test/SemaObjCXX/cstyle-block-pointer-cast.mm
new file mode 100644
index 0000000000..2796512ac0
--- /dev/null
+++ b/test/SemaObjCXX/cstyle-block-pointer-cast.mm
@@ -0,0 +1,23 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -fblocks %s
+// radar 7562285
+
+typedef int (^blocktype)(int a, int b);
+
+@interface A {
+    A* a;
+    id b;
+    Class c;
+}
+- (blocktype)Meth;
+@end
+
+@implementation A
+- (blocktype)Meth {
+        if (b)
+	  return (blocktype)b;
+        else if (a)
+          return (blocktype)a; // expected-error {{C-style cast from 'A *' to 'blocktype' (aka 'int (^)(int, int)') is not allowed}}
+        else
+          return (blocktype)c;
+}
+@end