[analyzer] Specify the C++ standard in more tests.

Makes life easier for downstream developers with different default standard.

llvm-svn: 375308
diff --git a/clang/test/Analysis/ptr-iter.cpp b/clang/test/Analysis/ptr-iter.cpp
index a35fae4..a94288c 100644
--- a/clang/test/Analysis/ptr-iter.cpp
+++ b/clang/test/Analysis/ptr-iter.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_analyze_cc1 %s -analyzer-output=text -verify \
+// RUN: %clang_analyze_cc1 %s -std=c++14 -analyzer-output=text -verify \
 // RUN: -analyzer-checker=core,alpha.nondeterminism.PointerIteration
 
 #include "Inputs/system-header-simulator-cxx.h"