[Bug ada/124025] bogus "potentially unsynchronized barrier" warning

[liam at liampwll dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124025

--- Comment #1 from Liam Powell <liam at liampwll dot com> ---
Created attachment 63620
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=63620&action=edit
fix on current master