Add run-time CHECK to smoke-test allocator overrides

third_party/tcmalloc/chromium/src/gperftools/tcmalloc.h

Index: third_party/tcmalloc/chromium/src/gperftools/tcmalloc.h
diff --git a/third_party/tcmalloc/chromium/src/gperftools/tcmalloc.h b/third_party/tcmalloc/chromium/src/gperftools/tcmalloc.h
index a3f036fec52823fb523753d98771eaba45200525..501abd6a06a4a6f562885749067fdb666195e54f 100644
--- a/third_party/tcmalloc/chromium/src/gperftools/tcmalloc.h
+++ b/third_party/tcmalloc/chromium/src/gperftools/tcmalloc.h
@@ -1,10 +1,10 @@
 /* Copyright (c) 2003, Google Inc.
  * All rights reserved.
- * 
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
- * 
+ *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ -14,7 +14,7 @@
  *     * Neither the name of Google Inc. nor the names of its
  * contributors may be used to endorse or promote products derived from
  * this software without specific prior written permission.
- * 
+ *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
@@ -53,6 +53,11 @@
 #define TC_VERSION_PATCH  ""
 #define TC_VERSION_STRING "gperftools 2.0"
 
+// When passed to mallopt() as first argument causes it to return
+// TC_MALLOPT_IS_OVERRIDDEN_BY_TCMALLOC. Used to detect the sanity of the
+// overriding mechanisms at runtime.
+#define TC_MALLOPT_IS_OVERRIDDEN_BY_TCMALLOC 0xbeef42
+
 // For struct mallinfo, it it's defined.
 #ifdef HAVE_STRUCT_MALLINFO
 // Malloc can be in several places on older versions of OS X.