[analyzer] Don't crash if a block doesn't have a type signature.

Currently, blocks instantiated in templates lose their "signature as
written"; it's not clear if this is intentional. Change the analyzer's
use of BlockDecl::getSignatureAsWritten to check whether or not the
signature is actually there.

<rdar://problem/13954714>

llvm-svn: 182497

1 files changed, 22 insertions, 0 deletions

diff --git a/clang/test/Analysis/templates.cpp b/clang/test/Analysis/templates.cpp
index faa5c1a7620..131794a7c93 100644
--- a/clang/test/Analysis/templates.cpp
+++ b/clang/test/Analysis/templates.cpp
@@ -48,3 +48,25 @@ void testNonTypeTemplateInstantiation() {
 #endif
 }
 
+namespace rdar13954714 {
+  template <bool VALUE>
+  bool blockInTemplate() {
+    return (^() {
+      return VALUE;
+    })();
+  }
+
+  // force instantiation
+  template bool blockInTemplate<true>();
+
+  template <bool VALUE>
+  void blockWithStatic() {
+    (void)^() {
+      static int x;
+      return ++x;
+    };
+  }
+
+  // force instantiation
+  template void blockWithStatic<true>();
+}