[macros] Support shrinking value transmutes #2581
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This was referenced Jun 9, 2025
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| /// | ||
| /// This macro can be invoked in `const` contexts. | ||
| #[macro_export] | ||
| macro_rules! transmute { |
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Need to document allow(shrink).
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In `transmute!`, support an `#![allow(shrink)]` attribute which is invoked as follows: transmute!(#![allow(shrink)] src); When this attribute is provided, `transmute!` will permit shrinking transmutes, in which the destination value may be smaller than the source value. Co-authored-by: Jack Wrenn <[email protected]> gherrit-pr-id: I46b18b4b1d10507b7e1d2e01b09dc4960cfcdce1
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Codecov ReportAttention: Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## main #2581 +/- ##
==========================================
- Coverage 88.91% 88.72% -0.19%
==========================================
Files 20 20
Lines 5312 5332 +20
==========================================
+ Hits 4723 4731 +8
- Misses 589 601 +12 ☔ View full report in Codecov by Sentry. 🚀 New features to boost your workflow:
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jswrenn
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Jun 10, 2025
Co-authored-by: Jack Wrenn <[email protected]>
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In
transmute!, support an#![allow(shrink)]attribute which isinvoked as follows:
transmute!(#![allow(shrink)] src);
When this attribute is provided,
transmute!will permit shrinkingtransmutes, in which the destination value may be smaller than the
source value.
Co-authored-by: Jack Wrenn [email protected]
This PR is on branch transmute-ref-dst.