assert impossible branch is impossible #150031
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…r=petrochenkov assert impossible branch is impossible The second half of this boolean or expression should not be possible with the current visitation implementation. Reasoning: - Innermost res will always be the first candidate visited. - the first scopes visited are `derive_helper` candidates, followed by a single step at `derive_helper_compat`: https://github.com/rust-lang/rust/blob/ee447067/compiler/rustc_resolve/src/ident.rs#L180-L192 - if there are candidates for both kinds the derive_helper candidate will always be innermost - there can only be one derive_helper_compat candidate - The first branch handles cases where the first candidate is a `derive_helper_compat` - if the first candidate is not a `derive_helper_compat` (as enforced by the first branch) and it is not a `derive_helper` (as enforced by the end of the second boolean expression) then then the first candidate and all subsequent candidates must be from later scope types, res cannot possibly be a `derive_helper_compat` r? `@petrochenkov`
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Rollup of 14 pull requests Successful merges: - #148756 (Warn on codegen attributes on required trait methods) - #148790 (Add new Tier-3 target: riscv64im-unknown-none-elf) - #149271 (feat: dlopen Enzyme) - #149459 (std: sys: fs: uefi: Implement set_times and set_perm) - #149771 (bootstrap readme: make easy to read when editor wrapping is not enabled) - #149856 (Provide an extended framework for type visit, for use in rust-analyzer) - #149950 (Simplify how inline asm handles `MaybeUninit`) - #150014 (Metadata loader cleanups) - #150021 (document that mpmc channels deliver an item to (at most) one receiver) - #150022 (Generate macro expansion for rust compiler crates docs) - #150029 (Update books) - #150031 (assert impossible branch is impossible) - #150034 (do not add `I-prioritize` when `F-*` labels are present) - #150036 (Use the embeddable filename for coverage artifacts) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 13 pull requests Successful merges: - #148756 (Warn on codegen attributes on required trait methods) - #148790 (Add new Tier-3 target: riscv64im-unknown-none-elf) - #149271 (feat: dlopen Enzyme) - #149459 (std: sys: fs: uefi: Implement set_times and set_perm) - #149771 (bootstrap readme: make easy to read when editor wrapping is not enabled) - #149856 (Provide an extended framework for type visit, for use in rust-analyzer) - #149950 (Simplify how inline asm handles `MaybeUninit`) - #150014 (Metadata loader cleanups) - #150021 (document that mpmc channels deliver an item to (at most) one receiver) - #150029 (Update books) - #150031 (assert impossible branch is impossible) - #150034 (do not add `I-prioritize` when `F-*` labels are present) - #150036 (Use the embeddable filename for coverage artifacts) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #150031 - yaahc:derive-helper-ambig-assert, r=petrochenkov assert impossible branch is impossible The second half of this boolean or expression should not be possible with the current visitation implementation. Reasoning: - Innermost res will always be the first candidate visited. - the first scopes visited are `derive_helper` candidates, followed by a single step at `derive_helper_compat`: https://github.com/rust-lang/rust/blob/ee447067/compiler/rustc_resolve/src/ident.rs#L180-L192 - if there are candidates for both kinds the derive_helper candidate will always be innermost - there can only be one derive_helper_compat candidate - The first branch handles cases where the first candidate is a `derive_helper_compat` - if the first candidate is not a `derive_helper_compat` (as enforced by the first branch) and it is not a `derive_helper` (as enforced by the end of the second boolean expression) then then the first candidate and all subsequent candidates must be from later scope types, res cannot possibly be a `derive_helper_compat` r? ``@petrochenkov``
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The second half of this boolean or expression should not be possible with the current visitation implementation.
Reasoning:
derive_helpercandidates, followed by a single step atderive_helper_compat: https://github.com/rust-lang/rust/blob/ee447067/compiler/rustc_resolve/src/ident.rs#L180-L192derive_helper_compatderive_helper_compat(as enforced by the first branch) and it is not aderive_helper(as enforced by the end of the second boolean expression) then then the first candidate and all subsequent candidates must be from later scope types, res cannot possibly be aderive_helper_compatr? @petrochenkov