[analyzer] Fix the bug in UninitializedObjectChecker caused by not handling block pointers

[george.karpenkov]

Summary

Causes crashes on most of our codebases.

[Szelethus]

Cool, thanks! ^-^

lib/StaticAnalyzer/Checkers/UninitializedObjectChecker.cpp

if (T->isUnionType()) {
       continue;
     }
 
     if (T->isArrayType()) {
       IsAnyFieldInitialized = true;
       continue;
     }
 
-    if (T->isPointerType() || T->isReferenceType()) {
+    if (T->isPointerType() || T->isReferenceType() || T->isBlockPointerType()) {
       if (isPointerOrReferenceUninit(FR, LocalChain))
         ContainsUninitField = true;
       continue;
     }
 
     if (isPrimitiveType(T)) {
       SVal V = State->getSVal(FieldVal);
 

 }
 
 // Note that pointers/references don't contain fields themselves, so in this
 // function we won't add anything to LocalChain.
 bool FindUninitializedFields::isPointerOrReferenceUninit(
     const FieldRegion *FR, FieldChainInfo LocalChain) {
 
   assert((FR->getDecl()->getType()->isPointerType() ||
-          FR->getDecl()->getType()->isReferenceType()) &&
+          FR->getDecl()->getType()->isReferenceType() ||
+          FR->getDecl()->getType()->isBlockPointerType()) &&
          "This method only checks pointer/reference objects!");
 
   SVal V = State->getSVal(FR);
 
   if (V.isUnknown() || V.getAs<loc::ConcreteInt>()) {
     IsAnyFieldInitialized = true;
     return false;
   }

test/Analysis/objcpp-uninitialized-object.mm

+// RUN: %clang_analyze_cc1 -analyzer-checker=core,alpha.cplusplus.UninitializedObject -std=c++11 -fblocks -verify %s
+
+typedef void (^myBlock) ();
+
+struct StructWithBlock {
+  int a;
+  myBlock z; // expected-note{{uninitialized field 'this->z'}}
+
+  StructWithBlock() : a(0), z(^{}) {}
+
+  // Miss initialization of field `z`.
+  StructWithBlock(int pA) : a(pA) {} // expected-warning{{1 uninitialized field at the end of the constructor call}}
+
+};
+
+void warnOnUninitializedBlock() {
+  StructWithBlock a(10);
+}
+
+void noWarningWhenInitialized() {
+  StructWithBlock a;
+}