add align_of! for computing alignment of DSTs
#576
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This probably could be implemented directly in terms of
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joshlf
requested changes
Oct 31, 2023
| #[macro_export] | ||
| macro_rules! align_of { | ||
| ($t:ty) => {{ | ||
| #[repr(C)] |
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Can you add a safety comment here that proves that this macro computes the correct value?
src/macro_util.rs
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| @@ -205,6 +205,26 @@ macro_rules! trailing_field_offset { | |||
| }}; | |||
| } | |||
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| /// Computes alignment of `$ty`. | |||
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Maybe also note that $ty doesn't need to be Sized?
34 tasks
The `align_of!` macro uses `trailing_field_offset!` to compute the alignment of DSTs with minimum alignments up to 65536. By contrast, `core::mem::align_of` does not support DSTs. Makes progress on #29.
joshlf
approved these changes
Oct 31, 2023
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The
align_of!macro usestrailing_field_offset!to compute the alignment of DSTs with minimum alignments up to 65536. By contrast,core::mem::align_ofdoes not support DSTs.We can use this for supplying the alignment argument required by
DstLayout::for_dst(introduced by #541).