The post was written two days ago, but the allocator versions are between three and six years old.<p>Nowadays, there are at least two different versions of tcmalloc: the one from <a href="https://github.com/google/tcmalloc/">https://github.com/google/tcmalloc/</a> is newer (it has rseq support, for example), and the version bundled in <a href="https://github.com/gperftools/gperftools">https://github.com/gperftools/gperftools</a>.