types: avoid accessing BoundMutex::inner in derived Debug #225
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We have a submodule `bound_mutex` whose purpose is to ensure that no deadlocks are possible. We do this by having a short submodule which only accesses the BoundMutex::inner member in the `get` and `set` methods. These methods lock the mutex and immediately unlock it. The member is never accessed by any other method. This is easy to check by searching the code for `inner`. HOWEVER, there is actually a hidden access to `inner` in the `#[derive(Debug)]` line on `BoundMutex`, and this access is incorrect. Rather than locking the mutex, cloning the Arc within, unlocking, then processing the cloned Arc, it just locks the mutex and then recursively calls stuff while it's locked. Stupid. Fix this by manually implementing `fmt::Debug`, calling `get` rather than directly accessing `inner`. Fixes #224.
uncomputable
approved these changes
Jun 29, 2024
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We have a submodule
bound_mutexwhose purpose is to ensure that no deadlocks are possible. We do this by having a short submodule which only accesses the BoundMutex::inner member in thegetandsetmethods. These methods lock the mutex and immediately unlock it. The member is never accessed by any other method. This is easy to check by searching the code forinner.HOWEVER, there is actually a hidden access to
innerin the#[derive(Debug)]line onBoundMutex, and this access is incorrect. Rather than locking the mutex, cloning the Arc within, unlocking, then processing the cloned Arc, it just locks the mutex and then recursively calls stuff while it's locked. Stupid.Fix this by manually implementing
fmt::Debug, callinggetrather than directly accessinginner.Fixes #224.