Use const-checking to forbid use of unstable features in const-stable functions #76807
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rust-highfive added the S-waiting-on-review 
`const_mut_refs` doesn't actually work in a `const` or `static`
ecstatic-morse force-pushed the const-checking-staged-api branch from 589e285 to abc7167 Compare 
| This is a good safety net for the actual changes! @bors r+ |
| 📌 Commit abc7167 has been approved by |
bors added S-waiting-on-bors Dylan-DPC-zz pushed a commit to Dylan-DPC-zz/rust that referenced this pull request Sep 19, 2020
…d-api, r=oli-obk Use const-checking to forbid use of unstable features in const-stable functions First step towards rust-lang#76618. Currently this code isn't ever hit because `qualify_min_const_fn` runs first and catches pretty much everything. One exception is `const_precise_live_drops`, which does not use the newly added code since it runs as part of a separate pass. Also contains some unrelated refactoring, which is split into separate commits. r? @oli-obk
Dylan-DPC-zz pushed a commit to Dylan-DPC-zz/rust that referenced this pull request Sep 19, 2020
…d-api, r=oli-obk Use const-checking to forbid use of unstable features in const-stable functions First step towards rust-lang#76618. Currently this code isn't ever hit because `qualify_min_const_fn` runs first and catches pretty much everything. One exception is `const_precise_live_drops`, which does not use the newly added code since it runs as part of a separate pass. Also contains some unrelated refactoring, which is split into separate commits. r? @oli-obk
This was referenced Sep 19, 2020
Dylan-DPC-zz pushed a commit to Dylan-DPC-zz/rust that referenced this pull request Sep 19, 2020
…d-api, r=oli-obk Use const-checking to forbid use of unstable features in const-stable functions First step towards rust-lang#76618. Currently this code isn't ever hit because `qualify_min_const_fn` runs first and catches pretty much everything. One exception is `const_precise_live_drops`, which does not use the newly added code since it runs as part of a separate pass. Also contains some unrelated refactoring, which is split into separate commits. r? @oli-obk
Dylan-DPC-zz pushed a commit to Dylan-DPC-zz/rust that referenced this pull request Sep 21, 2020
…d-api, r=oli-obk Use const-checking to forbid use of unstable features in const-stable functions First step towards rust-lang#76618. Currently this code isn't ever hit because `qualify_min_const_fn` runs first and catches pretty much everything. One exception is `const_precise_live_drops`, which does not use the newly added code since it runs as part of a separate pass. Also contains some unrelated refactoring, which is split into separate commits. r? @oli-obk
ecstatic-morse added a commit to ecstatic-morse/rust that referenced this pull request Sep 22, 2020
…d-api, r=oli-obk Use const-checking to forbid use of unstable features in const-stable functions First step towards rust-lang#76618. Currently this code isn't ever hit because `qualify_min_const_fn` runs first and catches pretty much everything. One exception is `const_precise_live_drops`, which does not use the newly added code since it runs as part of a separate pass. Also contains some unrelated refactoring, which is split into separate commits. r? @oli-obk
bors added a commit to rust-lang-ci/rust that referenced this pull request Sep 22, 2020
…atic-morse Rollup of 13 pull requests Successful merges: - rust-lang#72734 (Reduce duplicate in liballoc reserve error handling) - rust-lang#76131 (Don't use `zip` to compare iterators during pretty-print hack) - rust-lang#76150 (Don't recommend ManuallyDrop to customize drop order) - rust-lang#76275 (Implementation of Write for some immutable ref structs) - rust-lang#76489 (Add explanation for E0756) - rust-lang#76581 (do not ICE on bound variables, return `TooGeneric` instead) - rust-lang#76655 (Make some methods of `Pin` unstable const) - rust-lang#76783 (Only get ImplKind::Impl once) - rust-lang#76807 (Use const-checking to forbid use of unstable features in const-stable functions) - rust-lang#76888 (use if let instead of single match arm expressions) - rust-lang#76914 (extend `Ty` and `TyCtxt` lints to self types) - rust-lang#77022 (Reduce boilerplate for BytePos and CharPos) - rust-lang#77032 (lint missing docs for extern items) Failed merges: r? `@ghost`
ecstatic-morse added a commit to ecstatic-morse/rust that referenced this pull request Sep 22, 2020
…tor, r=oli-obk Remove `qualify_min_const_fn` ~~Blocked on rust-lang#76807 (the first six commits).~~ With this PR, all checks in `qualify_min_const_fn` are replicated in `check_consts`, and the former is no longer invoked. My goal was to have as few changes to test output as possible, since making sweeping changes to the code *while* doing big batches of diagnostics updates turned out to be a headache. To this end, there's a few `HACK`s in `check_consts` to achieve parity with `qualify_min_const_fn`. The new system that replaces `is_min_const_fn` is referred to as "const-stability" My end goal for the const-stability rules is this: * Const-stability is only applicable to functions defined in `staged_api` crates. * All functions not marked `rustc_const_unstable` are considered "const-stable". - NB. This is currently not implemented. `#[unstable]` functions are also const-unstable. This causes problems when searching for feature gates. - All "const-unstable" functions have an associated feature gate * const-stable functions can only call other const-stable functions - `allow_internal_unstable` can be used to circumvent this. * All const-stable functions are subject to some additional checks (the ones that were unique to `qualify_min_const_fn`) The plan is to remove each `HACK` individually in subsequent PRs. That way, changes to error message output can be reviewed in isolation.
bors added a commit to rust-lang-ci/rust that referenced this pull request Sep 23, 2020
…r, r=oli-obk Remove `qualify_min_const_fn` ~~Blocked on rust-lang#76807 (the first six commits).~~ With this PR, all checks in `qualify_min_const_fn` are replicated in `check_consts`, and the former is no longer invoked. My goal was to have as few changes to test output as possible, since making sweeping changes to the code *while* doing big batches of diagnostics updates turned out to be a headache. To this end, there's a few `HACK`s in `check_consts` to achieve parity with `qualify_min_const_fn`. The new system that replaces `is_min_const_fn` is referred to as "const-stability" My end goal for the const-stability rules is this: * Const-stability is only applicable to functions defined in `staged_api` crates. * All functions not marked `rustc_const_unstable` are considered "const-stable". - NB. This is currently not implemented. `#[unstable]` functions are also const-unstable. This causes problems when searching for feature gates. - All "const-unstable" functions have an associated feature gate * const-stable functions can only call other const-stable functions - `allow_internal_unstable` can be used to circumvent this. * All const-stable functions are subject to some additional checks (the ones that were unique to `qualify_min_const_fn`) The plan is to remove each `HACK` individually in subsequent PRs. That way, changes to error message output can be reviewed in isolation.
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First step towards #76618.
Currently this code isn't ever hit because
qualify_min_const_fnruns first and catches pretty much everything. One exception isconst_precise_live_drops, which does not use the newly added code since it runs as part of a separate pass.Also contains some unrelated refactoring, which is split into separate commits.
r? @oli-obk