Clarify the usage of "hints" in const_eval. #26683
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r? @huonw (rust_highfive has picked a reviewer for you, use r? to override) |
eefriedman
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☔ The latest upstream changes (presumably #26757) made this pull request unmergeable. Please resolve the merge conflicts. |
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r? @pnkfelix (random person from the compiler subteam) |
| substs), | ||
| Some(&**ty)) | ||
| if let ExprTypeChecked = ty_hint { | ||
| let substs = tcx.node_id_item_substs(e.id).substs; |
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(It took me a little while to convince myself that this ends up being equivalent to the effect we were getting before via the get_substs parameter, but I now believe the tables in the tcx should match even in the case where check::_match::check_pat was passing in a closure that calls fcx.item_substs(), so this should be okay.)
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@eefriedman I'm basically all in favor of this PR. I've put some feedback up above but you can treat it as an r=me after a rebase. |
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The "hint" mechanism is essentially used as a workaround to compute types for expressions which have not yet been type-checked. This commit clarifies that usage, and limits the effects to the places where it is currently necessary. Fixes rust-lang#26210.
eefriedman
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Rebased. |
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ping @pnkfelix |
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@bors r+ |
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📌 Commit 6bdfb05 has been approved by |
The "hint" mechanism is essentially used as a workaround to compute types for expressions which have not yet been type-checked. This commit clarifies that usage, and limits the effects to the places where it is currently necessary. Fixes #26210.
The "hint" mechanism is essentially used as a workaround to compute
types for expressions which have not yet been type-checked. This
commit clarifies that usage, and limits the effects to the places
where it is currently necessary.
Fixes #26210.