Unbreak build with gcc 4.3: provide missed includes and silence most annoying warnings.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47367 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/StringExtras.cpp b/lib/Support/StringExtras.cpp
index ac17696..1fae4fa 100644
--- a/lib/Support/StringExtras.cpp
+++ b/lib/Support/StringExtras.cpp
@@ -12,6 +12,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/ADT/StringExtras.h"
+#include <cstring>
 using namespace llvm;
 
 /// getToken - This function extracts one token from source, ignoring any