Add -Wstring-plus-int, which warns on "str" + int and int + "str".

It doesn't warn if the integer is known at compile time and within
the bounds of the string.

Discussion: http://comments.gmane.org/gmane.comp.compilers.clang.scm/47203
llvm-svn: 151943
diff --git a/clang/test/SemaCXX/array-bounds-ptr-arith.cpp b/clang/test/SemaCXX/array-bounds-ptr-arith.cpp
index ce1ace6..16e2567 100644
--- a/clang/test/SemaCXX/array-bounds-ptr-arith.cpp
+++ b/clang/test/SemaCXX/array-bounds-ptr-arith.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -verify -Warray-bounds-pointer-arithmetic %s
+// RUN: %clang_cc1 -verify -Wno-string-plus-int -Warray-bounds-pointer-arithmetic %s
 
 void swallow (const char *x) { (void)x; }
 void test_pointer_arithmetic(int n) {