https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96942
--- Comment #33 from Dmitriy Ovdienko <dmitriy.ovdienko at gmail dot com> --- @Jonathan Wakely I have one idea to improve code of p_m_r I expect that allocation are very rare operation. If true, it makes sense to add __unlikelly to `if (!__p)` inside the `do_allocate` member function
