Optimisation: avoid emitting type tests for verify bounds that always hold#152579
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amandasystems wants to merge 1 commit intorust-lang:mainfrom
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Optimisation: avoid emitting type tests for verify bounds that always hold#152579amandasystems wants to merge 1 commit intorust-lang:mainfrom
amandasystems wants to merge 1 commit intorust-lang:mainfrom
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… hold This makes more sense than you'd imagine since empty `All` bounds which always hold is relatively common.
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Feb 13, 2026
| if bound.must_hold() { | ||
| debug!("Bound {bound:?} always holds; emitting no type test."); | ||
| return; | ||
| } |
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this feels potentially quite surprising to me.
can we instead avoid constructing these verify bounds in the first place?
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This makes more sense than you'd imagine since empty
Allbounds which always hold are is a relatively common use of them and a bound that always holds produces no promoted constraints.r? @lcnr