First reported here: https://plus.google.com/104877287288155269055/posts/grHDgRNc1gi My hypothesis is that we've always had global new/delete overriding turned on without realizing it. When I turned off symbol hiding by default to avoiding compiling JSC multiple times into libraries and applications this badness was exposed to the world.
*** This bug has been marked as a duplicate of bug 89358 ***