ba71a63fde
Fix transmutes between pointers in different address spaces (e.g. fn ptrs on AVR) Currently, this causes a verifier error (https://godbolt.org/z/YYohed4bj), since it uses `bitcast`, which can't convert between address spaces. Uncovered due to https://github.com/rust-lang/rust/pull/105545#discussion_r1045269309 r? `@bjorn3`
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