Index: cfe/trunk/lib/StaticAnalyzer/Core/CallEvent.cpp
===================================================================
--- cfe/trunk/lib/StaticAnalyzer/Core/CallEvent.cpp
+++ cfe/trunk/lib/StaticAnalyzer/Core/CallEvent.cpp
@@ -837,7 +837,7 @@
 ArrayRef<ParmVarDecl*> BlockCall::parameters() const {
   const BlockDecl *D = getDecl();
   if (!D)
-    return nullptr;
+    return None;
   return D->parameters();
 }
 
Index: cfe/trunk/test/Analysis/osobject-retain-release.cpp
===================================================================
--- cfe/trunk/test/Analysis/osobject-retain-release.cpp
+++ cfe/trunk/test/Analysis/osobject-retain-release.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_analyze_cc1 -analyze -analyzer-checker=core,osx -analyzer-output=text -verify %s
+// RUN: %clang_analyze_cc1 -fblocks -analyze -analyzer-output=text\
+// RUN:                    -analyzer-checker=core,osx -verify %s
 
 struct OSMetaClass;
 
@@ -399,3 +400,11 @@
   arr->release(); // +0
   return arr->getCount();
 }
+
+OSObject *getObject();
+typedef bool (^Blk)(OSObject *);
+
+void test_escape_to_unknown_block(Blk blk) {
+  blk(getObject()); // no-crash
+}
+