[Bug libstdc++/58931] condition_variable::wait_until overflowed by large time_point

[aaron at aarongraham dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58931

--- Comment #5 from Aaron Graham <aaron at aarongraham dot com> ---
Created attachment 43261
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43261&action=edit
Patch to check for overflow