2022.03.07 release notes. What is "semaphore link"

Questions & Answers
1

I noticed that there is a fixed item in 2022.03.07 release note:

IL2CPP: Avoid a semaphore link in the IL2CPP runtime that can occur during lock contention for multiple threads. (UUM-40104)

What is a “semaphore link” means in the above description?
Is that a kind of expression for “dead lock” or any other multiple thread status that I never heard.

The reason I need to know the specific meanings for this item is our project has a random ANR problem.
We need to know if this update gonna fix that ANR.

Or any specific information for UUM-40104 ?

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2

Thanks for mentioning this. The word “link” should have been “leak” in the release notes. I made a typo when I wrote that release notes entry, sorry!

Unfortunately UUM-40104 is not a public bug report, so I can’t link to it on the issue tracker. The problem was related to a race condition in the libil2cpp runtime code that could allow OS semaphore objects to leak when many threads are contending for C# Monitors (usually the lock statement). On most operating systems, this isn’t noticeable, but some have a limited number of semaphores per process. On those operating systems this bug was a problem.