Use align_offset to check alignment
#176
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Since this method isn't available in 1.34 we'd have to put the change behind a feature gate. But also, a compiler "should" be able to see that even the integer form of the pointer doesn't escape and so I would hope that the cast does not hurt optimizations in practice. |
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I want the basics of the PR, but since sarah hasn't replied i'll just accept it as-is and fix it up with a new feature. |
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check for alignment using
(ptr as *const ()).align_offset(align) == 0This is in a way better than
ptr as usize % align == 0, because casting a pointer to an integer has the side effect that it exposes the pointer's provenance, which may theoretically inhibit some compiler optimizations.