https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113874
--- Comment #29 from Michael Matz <matz at gcc dot gnu.org> --- It not only can call malloc. As the backtrace of H.J. shows, it quite clearly _does_ so :-) That's why there is talk earlier in this report about potentially not using malloc as one-time allocator for thread-local areas at all, or allocate the memory at a different time that from __tls_get_addr.