The "jump magic" codepath was never written, and would have involved a lot
of low-level and platform/processor/compiler specific work.
A better solution is for compilers to treat the function call in the jump
table functions as a tail call, which would effectively produce the same
result in a portable way.
Clang already has a way to do this that we could add later. But this wouldn't
need a separate "jump magic" section.
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