[Bug libstdc++/66624] libstdc++ iostream uninitialized data

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66624

--- Comment #4 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I'm not sure, but I don't yet see how _M_state wouldn't get initialized.