[Bug libfortran/66756] libgfortran: ThreadSanitizer: lock-order-inversion

[tkoenig at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66756

--- Comment #11 from Thomas Koenig <tkoenig at gcc dot gnu.org> ---
Created attachment 42250
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=42250&action=edit
Proposed patch

This patch is an attempt at getting rid of the lock-order
inversion.  It seems to do the right thing, and survives
both regression-testing and the thread sanitizer.

It is not yet complete (comments are not adjusted).

I would be grateful if somebody had a way to stress-test it.