Make const BorrowMut require const Borrow and make const Fn require const FnMut
#147939
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This file previously contained an error annotation with incorrect syntax. Remove this annotation, as per the dev guide, since this is marked as known-bug. https://rustc-dev-guide.rust-lang.org/tests/ui.html#known-bugs
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Oct 21, 2025
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| (const || (()).foo())(); | ||
| // ^ ERROR: cannot call non-const method `<() as Foo>::foo` in constant functions |
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We sometimes leave these in to keep some context for when someone fixes the test. Fine here tho
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lcnr
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Oct 23, 2025
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idk if that should be part of this PR, regardless r? @oli-obk |
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@bors r+ rollup |
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…uwer Rollup of 11 pull requests Successful merges: - #147939 (Make `const BorrowMut` require `const Borrow` and make `const Fn` require `const FnMut`) - #149734 (Mirror GCC 9.5.0) - #149767 (Tidying up tests/ui/issues 33 tests [4/N]) - #149804 (chore: fix some minor issues in the comments) - #149967 (custom `VaList` layout for Hexagon) - #150025 (dont create unnecessary `DefId`s under mgca) - #150032 (Use annotate-snippet as default emitter on stable) - #150033 (Add try_as_dyn and try_as_dyn_mut) - #150042 (rustc-dev-guide subtree update) - #150063 (Remove deny of manual-let-else) - #150064 (std: io: error: Add comment for UEFI unpacked repr use) Failed merges: - #150044 (Avoid unhelpful suggestion when crate name is invalid) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #147939 - theemathas:add-const-supertrait, r=oli-obk Make `const BorrowMut` require `const Borrow` and make `const Fn` require `const FnMut` This makes it consistent with other const traits in the standard library with supertraits. I am currently unsure if `const FnMut` should require `const FnOnce` or not. See [zulip discussion](https://rust-lang.zulipchat.com/#narrow/channel/146212-t-compiler.2Fconst-eval/topic/.5Bconst.5D.20implied.20bounds.20for.20implicit.20trait.20bounds/near/546152748).
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…uwer Rollup of 11 pull requests Successful merges: - rust-lang/rust#147939 (Make `const BorrowMut` require `const Borrow` and make `const Fn` require `const FnMut`) - rust-lang/rust#149734 (Mirror GCC 9.5.0) - rust-lang/rust#149767 (Tidying up tests/ui/issues 33 tests [4/N]) - rust-lang/rust#149804 (chore: fix some minor issues in the comments) - rust-lang/rust#149967 (custom `VaList` layout for Hexagon) - rust-lang/rust#150025 (dont create unnecessary `DefId`s under mgca) - rust-lang/rust#150032 (Use annotate-snippet as default emitter on stable) - rust-lang/rust#150033 (Add try_as_dyn and try_as_dyn_mut) - rust-lang/rust#150042 (rustc-dev-guide subtree update) - rust-lang/rust#150063 (Remove deny of manual-let-else) - rust-lang/rust#150064 (std: io: error: Add comment for UEFI unpacked repr use) Failed merges: - rust-lang/rust#150044 (Avoid unhelpful suggestion when crate name is invalid) r? `@ghost` `@rustbot` modify labels: rollup
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This makes it consistent with other const traits in the standard library with supertraits.
I am currently unsure if
const FnMutshould requireconst FnOnceor not. See zulip discussion.