Tighten the !range bounds on alignments in vtables#152929
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rust-bors[bot] merged 1 commit intorust-lang:mainfrom Feb 21, 2026
Merged
Tighten the !range bounds on alignments in vtables#152929rust-bors[bot] merged 1 commit intorust-lang:mainfrom
!range bounds on alignments in vtables#152929rust-bors[bot] merged 1 commit intorust-lang:mainfrom
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…lignment from a vtable
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r? @adwinwhite rustbot has assigned @adwinwhite. Use Why was this reviewer chosen?The reviewer was selected based on:
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@rustbot reroll |
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Oh, looks like the bot isn't picking from the narrower group. |
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Nice. @bors r+ |
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…r=mati865 Tighten the `!range` bounds on alignments in vtables Right now we're only telling LLVM that they're non-zero, but alignments must be powers of two so can't be more than `isize::MAX+1`. And we actually never emit anything beyond LLVM's limit of 2²⁹, so outside of 16-bit targets the limit is that. (Pulled out from rust-lang#152867 which is starting to have too much in it.)
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Rollup of 6 pull requests Successful merges: - #152929 (Tighten the `!range` bounds on alignments in vtables) - #151603 (Stabilize `str_as_str`) - #152878 (Remove two more flaky assertions from `oneshot` tests) - #152915 (Error on attempt to construct scalable vector type) - #152925 (Improve runtest revision redundant cfg check) - #152928 (Update wasm-component-ld)
| pub fn max_for_target(tdl: &TargetDataLayout) -> Align { | ||
| let pointer_bits = tdl.pointer_size().bits(); | ||
| if let Ok(pointer_bits) = u8::try_from(pointer_bits) | ||
| && pointer_bits <= Align::MAX.pow2 |
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Question, are we taking the max between Align::MAX.pow2 and pointer_bits, or between Align::MAX.pow2 and pointer_bits - 1?
Could this be what we actually want?
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| && pointer_bits <= Align::MAX.pow2 | |
| && pointer_bits - 1 <= Align::MAX.pow2 |
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Rollup of 6 pull requests Successful merges: - #152929 (Tighten the `!range` bounds on alignments in vtables) - #151603 (Stabilize `str_as_str`) - #152878 (Remove two more flaky assertions from `oneshot` tests) - #152915 (Error on attempt to construct scalable vector type) - #152925 (Improve runtest revision redundant cfg check) - #152928 (Update wasm-component-ld)
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Rollup merge of #152929 - scottmcm:better-alignment-ranges, r=mati865 Tighten the `!range` bounds on alignments in vtables Right now we're only telling LLVM that they're non-zero, but alignments must be powers of two so can't be more than `isize::MAX+1`. And we actually never emit anything beyond LLVM's limit of 2²⁹, so outside of 16-bit targets the limit is that. (Pulled out from #152867 which is starting to have too much in it.)
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Right now we're only telling LLVM that they're non-zero, but alignments must be powers of two so can't be more than
isize::MAX+1. And we actually never emit anything beyond LLVM's limit of 2²⁹, so outside of 16-bit targets the limit is that.(Pulled out from #152867 which is starting to have too much in it.)