Using mimalloc as system allocator

Is `mimalloc` in a state where I could use it as the system allocator?

Haiku is looking at options to replace the current hoard2 allocator in it's `libc` equivalent (`libroot`). I've given it a try, but might be passing the wrong defines/flags to make it work correctly, as I'm running into page faults. Should I be using a 1.x branch instead?

Start by reviewing mimalloc's documented system-allocator integration and the defines or flags used by the Haiku libroot experiment. Compare the attempted setup with the supported branches, including the 1.x branch, and reproduce the page faults. Done means establishing whether mimalloc can be used there and identifying the required configuration or confirming an incompatibility.

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