Fixed warnings reported by clang compiler.

runtime/third_party/jscre/pcre_internal.h

 /* This is JavaScriptCore's variant of the PCRE library. While this library
 started out as a copy of PCRE, many of the features of PCRE have been
 removed. This library now supports only the regular expression features
 required by the JavaScript language specification, and has only the functions
 needed by JavaScriptCore and the rest of WebKit.
 
                  Originally written by Philip Hazel
            Copyright (c) 1997-2006 University of Cambridge
     Copyright (C) 2002, 2004, 2006, 2007 Apple Inc. All rights reserved.
 
@@ skipping 65 matching lines @@
 
 #define lcc_offset      0
 #define fcc_offset    128
 #define cbits_offset  256
 #define ctypes_offset (cbits_offset + cbit_length)
 #define tables_length (ctypes_offset + 128)
 
 #ifndef DFTABLES
 
 // TODO(xxx): Hook this up to something that checks assertions.
-#define ASSERT(x) if (!(x)) *(reinterpret_cast<int*>(NULL)) = NULL
-#define ASSERT_NOT_REACHED() *(reinterpret_cast<int*>(NULL)) = NULL
+#define ASSERT(x) if (!(x)) *(reinterpret_cast<volatile int*>(NULL)) = NULL

[Kevin Millikin (Google), 2013/01/11 11:30:59]

Drive by: shouldn't this be fixed upstream in WebKit?

And if you're going to change it, you should also change it so it can't capture
an 'else'.

+#define ASSERT_NOT_REACHED() *(reinterpret_cast<volatile int*>(NULL)) = NULL
 
 #ifdef WIN32
 #pragma warning(disable: 4232)
 #pragma warning(disable: 4244)
 #endif
 
 #include "./pcre.h"
 
 /* The value of LINK_SIZE determines the number of bytes used to store links as
 offsets within the compiled regex. The default is 2, which allows for compiled
@@ skipping 321 matching lines @@
 that one of the source files. They have to have external linkage, but
 but are not part of the public API and so not exported from the library. */
 
 extern int kjs_pcre_ucp_othercase(unsigned);
 extern bool kjs_pcre_xclass(int, const unsigned char*);
 
 } }  // namespace dart::jscre
 #endif
 
 #endif  // THIRD_PARTY_JSCRE_PCRE_INTERNAL_H_