[Bug rtl-optimization/126290] x86-64 -fPIC drops `register asm` operands of an `asm` when a `__thread` address is another operand

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126290

--- Comment #3 from Drea Pinski <pinskia at gcc dot gnu.org> ---
Note the documentation warns even about implicit libcalls too.