Fix: Crystal::RWLock should be a struct
#14345
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The Crystal::RWLock type is used to protect the GC against fiber context switches, to avoid the GC interrupting a thread while it is switching contexts, or starting a collection while a thread was preempted by the kernel while it was switching the fiber context. Problem is: Crystal::RWLock is a class, and thus depends on the GC to be allocated, and we end up in an infinite loop: GC depends on Crystal::RWLock that itself depends on GC, ... The weirdest part is that it's working, and I have no idea how.
straight-shoota
approved these changes
Mar 5, 2024
straight-shoota
changed the title
Crystal::RWLock should be a struct
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The Crystal::RWLock type is used to protect the GC against fiber context switches, to avoid the GC interrupting a thread while it is switching to another fiber, or starting a collection while a thread was preempted by the kernel while it was switching to another fiber.
Problem is: Crystal::RWLock is a class, and as such depends on the GC to be allocated, and... we end up in an infinite loop: GC <-> Crystal::RWLock.
The weirdest part is that it's working, and I have no idea how.