https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112089
Bug ID: 112089
Summary: std::shared_lock::unlock should throw
operation_not_permitted instead
resource_deadlock_would_occur
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: d at ilvokhin dot com
Target Milestone: ---
Based on C++ standard wording, when we call unlock and don't own anything we
should throw operation_not_permitted. Sec 33.6.5.5.3 from here
(https://eel.is/c++draft/thread.lock.shared.locking#25.1):
> void unlock();
> <...>
> Error conditions:
> operation_not_permitted — if on entry owns is false.
But current implementation throws resource_deadlock_would_occur instead:
https://github.com/gcc-mirror/gcc/blob/458db9b6149b2e9bef94ab76909eb914ed9f675a/libstdc%2B%2B-v3/include/std/shared_mutex#L823
It doesn't change much, just a little inconsistency.
