d5bb7b866e
See https://bugzilla.redhat.com/2336915 See https://reviews.llvm.org/D41784?id= See https://github.com/androm3da/optviewer-demo/issues/4#issuecomment-718787822 Fixes https://github.com/llvm/llvm-project/issues/62403. The race condition happened when the demangler_proc was being set. The locking mechanism itself happened too late. This way, the lock always exists (to avoid a race when creating it) and is always used when *creating* demangler_proc. (cherry picked from commit e0f8898e1d432ab4fdcaf353bf87a1d3cf36491a)