[Bug preprocessor/58770] GCC very slow compiling with #pragma once

[sjames at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58770

--- Comment #8 from Sam James <sjames at gcc dot gnu.org> ---
(See the thread at
https://inbox.sourceware.org/gcc-patches/6027e3bb-99f9-573b-ff5e-ea1a48882...@acm.org/.)