Teach -Wuninitialized about ObjC fast enumeration loops.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@124347 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/SemaObjC/uninit-variables.m b/test/SemaObjC/uninit-variables.m
new file mode 100644
index 0000000..f3917f3
--- /dev/null
+++ b/test/SemaObjC/uninit-variables.m
@@ -0,0 +1,27 @@
+// RUN: %clang_cc1 -fsyntax-only -Wuninitialized -fsyntax-only -fblocks %s -verify
+
+// Duplicated from uninit-variables.c.
+// Test just to ensure the analysis is working.
+int test1() {
+  int x; // expected-warning{{use of uninitialized variable 'x'}} expected-note{{add initialization to silence this warning}}
+  return x; // expected-note{{variable 'x' is possibly uninitialized when used here}}
+}
+
+// Test ObjC fast enumeration.
+void test2() {
+  id collection = 0;
+  for (id obj in collection) {
+    if (0 == obj) // no-warning
+      break;
+  }
+}
+
+void test3() {
+  id collection = 0;
+  id obj;
+  for (obj in collection) { // no-warning
+    if (0 == obj) // no-warning
+      break;
+  }
+}
+