Ralf Jung a0215d8e46 Re-do recursive const stability checks ... Fundamentally, we have *three* disjoint categories of functions: 1. const-stable functions 2. private/unstable functions that are meant to be callable from const-stable functions 3. functions that can make use of unstable const features This PR implements the following system: - `#[rustc_const_stable]` puts functions in the first category. It may only be applied to `#[stable]` functions. - `#[rustc_const_unstable]` by default puts functions in the third category. The new attribute `#[rustc_const_stable_indirect]` can be added to such a function to move it into the second category. - `const fn` without a const stability marker are in the second category if they are still unstable. They automatically inherit the feature gate for regular calls, it can now also be used for const-calls. Also, several holes in recursive const stability checking are being closed. There's still one potential hole that is hard to avoid, which is when MIR building automatically inserts calls to a particular function in stable functions -- which happens in the panic machinery. Those need to *not* be `rustc_const_unstable` (or manually get a `rustc_const_stable_indirect`) to be sure they follow recursive const stability. But that's a fairly rare and special case so IMO it's fine. The net effect of this is that a `#[unstable]` or unmarked function can be constified simply by marking it as `const fn`, and it will then be const-callable from stable `const fn` and subject to recursive const stability requirements. If it is publicly reachable (which implies it cannot be unmarked), it will be const-unstable under the same feature gate. Only if the function ever becomes `#[stable]` does it need a `#[rustc_const_unstable]` or `#[rustc_const_stable]` marker to decide if this should also imply const-stability. Adding `#[rustc_const_unstable]` is only needed for (a) functions that need to use unstable const lang features (including intrinsics), or (b) `#[stable]` functions that are not yet intended to be const-stable. Adding `#[rustc_const_stable]` is only needed for functions that are actually meant to be directly callable from stable const code. `#[rustc_const_stable_indirect]` is used to mark intrinsics as const-callable and for `#[rustc_const_unstable]` functions that are actually called from other, exposed-on-stable `const fn`. No other attributes are required.		2024-10-25 20:31:40 +02:00
..
auxiliary	Re-do recursive const stability checks	2024-10-25 20:31:40 +02:00
const_derives	Be better at enforcing that const_conditions is only called on const items	2024-10-24 09:46:36 +00:00
effects	Re-do recursive const stability checks	2024-10-25 20:31:40 +02:00
specialization	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
assoc-type-const-bound-usage-0.rs	Add support for ~const item bounds	2024-10-24 23:43:31 +00:00
assoc-type-const-bound-usage-1.rs	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
assoc-type-const-bound-usage-1.stderr	Add support for ~const item bounds	2024-10-24 23:43:31 +00:00
assoc-type-const-bound-usage-fail-2.rs	Add support for ~const item bounds	2024-10-24 23:43:31 +00:00
assoc-type-const-bound-usage-fail-2.stderr	Add support for ~const item bounds	2024-10-24 23:43:31 +00:00
assoc-type-const-bound-usage-fail.rs	Add support for ~const item bounds	2024-10-24 23:43:31 +00:00
assoc-type-const-bound-usage-fail.stderr	Add support for ~const item bounds	2024-10-24 23:43:31 +00:00
assoc-type.rs	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
assoc-type.stderr	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
attr-misuse.rs
attr-misuse.stderr
call-const-closure.rs	Add tests	2024-10-24 09:46:36 +00:00
call-const-closure.stderr	Add tests	2024-10-24 09:46:36 +00:00
call-const-in-tilde-const.rs	Add tests	2024-10-24 09:46:36 +00:00
call-const-in-tilde-const.stderr	Add tests	2024-10-24 09:46:36 +00:00
call-const-trait-method-fail.rs
call-const-trait-method-fail.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
call-const-trait-method-pass.rs
call-const-trait-method-pass.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
call-generic-in-impl.rs
call-generic-in-impl.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
call-generic-method-chain.rs	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
call-generic-method-chain.stderr	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
call-generic-method-dup-bound.rs	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
call-generic-method-dup-bound.stderr	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
call-generic-method-fail.rs
call-generic-method-nonconst-bound.rs
call-generic-method-nonconst.rs
call-generic-method-nonconst.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
call-generic-method-pass.rs	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
call-generic-method-pass.stderr	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
call.rs
const-and-non-const-impl.rs
const-and-non-const-impl.stderr
const-bound-in-host.rs	Add tests	2024-10-24 09:46:36 +00:00
const-bound-in-host.stderr	Add tests	2024-10-24 09:46:36 +00:00
const-bound-on-not-const-associated-fn.rs	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
const-bound-on-not-const-associated-fn.stderr	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
const-bounds-non-const-trait.rs	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-bounds-non-const-trait.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-check-fns-in-const-impl.rs	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
const-check-fns-in-const-impl.stderr	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
const-closure-parse-not-item.rs
const-closure-parse-not-item.stderr
const-closure-trait-method-fail.rs
const-closure-trait-method-fail.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-closure-trait-method.rs
const-closure-trait-method.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-closures.rs
const-closures.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-default-method-bodies.rs
const-default-method-bodies.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-drop-bound.rs
const-drop-bound.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-drop-fail-2.precise.stderr
const-drop-fail-2.rs
const-drop-fail-2.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-drop-fail-2.stock.stderr
const-drop-fail.precise.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-drop-fail.rs
const-drop-fail.stock.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-drop.precise.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-drop.rs
const-drop.stock.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-fns-are-early-bound.rs	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
const-impl-norecover.rs
const-impl-norecover.stderr
const-impl-recovery.rs
const-impl-recovery.stderr
const-impl-requires-const-trait.rs	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
const-impl-requires-const-trait.stderr	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
const-impl-trait.rs	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
const-in-closure.rs	Add tests	2024-10-24 09:46:36 +00:00
const-in-closure.stderr	Add tests	2024-10-24 09:46:36 +00:00
const-trait-bounds-trait-objects.rs
const-trait-bounds-trait-objects.stderr
const-trait-bounds.rs
const-trait-bounds.stderr
cross-crate-default-method-body-is-const.rs
cross-crate.gatednc.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
cross-crate.rs
cross-crate.stock.stderr
cross-crate.stocknc.stderr
default-method-body-is-const-body-checking.rs
default-method-body-is-const-same-trait-ck.rs
default-method-body-is-const-same-trait-ck.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
default-method-body-is-const-with-staged-api.rs
do-not-const-check-override.rs
do-not-const-check.rs
dont-observe-host-opaque.rs	Add tests	2024-10-24 09:46:36 +00:00
dont-observe-host-opaque.stderr	Add tests	2024-10-24 09:46:36 +00:00
dont-observe-host.rs	Add tests	2024-10-24 09:46:36 +00:00
dont-observe-host.stderr	Add tests	2024-10-24 09:46:36 +00:00
feature-gate.gated.stderr
feature-gate.rs
feature-gate.stock.stderr
fn-ptr-lub.rs	Add tests	2024-10-24 09:46:36 +00:00
fn-ptr-lub.stderr	Add tests	2024-10-24 09:46:36 +00:00
function-pointer-does-not-require-const.rs
gate.rs
gate.stderr
generic-bound.rs
generic-bound.stderr
hir-const-check.rs	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
hir-const-check.stderr	Add next-solver to more effects tests	2024-10-24 09:46:36 +00:00
ice-119717-constant-lifetime.rs
ice-119717-constant-lifetime.stderr
ice-120503-async-const-method.rs
ice-120503-async-const-method.stderr
ice-121536-const-method.rs
ice-121536-const-method.stderr
ice-123664-unexpected-bound-var.rs	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
ice-123664-unexpected-bound-var.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
ice-124857-combine-effect-const-infer-vars.rs
ice-124857-combine-effect-const-infer-vars.stderr
ice-126148-failed-to-normalize.rs
ice-126148-failed-to-normalize.stderr
impl-tilde-const-trait.rs
impl-tilde-const-trait.stderr
impl-with-default-fn-fail.rs
impl-with-default-fn-fail.stderr
impl-with-default-fn-pass.rs
inherent-impl-const-bounds.rs
inherent-impl.rs
inherent-impl.stderr
inline-incorrect-early-bound-in-ctfe.rs
inline-incorrect-early-bound-in-ctfe.stderr
issue-79450.rs	Re-do recursive const stability checks	2024-10-25 20:31:40 +02:00
issue-79450.stderr	Re-do recursive const stability checks	2024-10-25 20:31:40 +02:00
issue-88155.rs
issue-88155.stderr
issue-92111.rs
issue-92111.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
issue-92230-wf-super-trait-env.rs
issue-100222.rs
issue-102156.rs
issue-102156.stderr
issue-102985.rs
issue-102985.stderr
issue-103677.rs
item-bound-entailment-fails.rs	Add tests	2024-10-24 09:46:36 +00:00
item-bound-entailment-fails.stderr	Add tests	2024-10-24 09:46:36 +00:00
item-bound-entailment.rs	Add tests	2024-10-24 09:46:36 +00:00
item-bound-entailment.stderr	Add tests	2024-10-24 09:46:36 +00:00
match-non-const-eq.gated.stderr
match-non-const-eq.rs
match-non-const-eq.stock.stderr
mbe-bare-trait-objects-const-trait-bounds.rs
mbe-const-trait-bound-theoretical-regression.rs
mbe-const-trait-bound-theoretical-regression.stderr
mbe-dyn-const-2015.rs
mutually-exclusive-trait-bound-modifiers.rs
mutually-exclusive-trait-bound-modifiers.stderr
nested-closure.rs
non-const-op-const-closure-non-const-outer.rs
non-const-op-const-closure-non-const-outer.stderr
non-const-op-in-closure-in-const.rs
non-const-op-in-closure-in-const.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
predicate-entailment-fails.rs	Add tests	2024-10-24 09:46:36 +00:00
predicate-entailment-fails.stderr	Add tests	2024-10-24 09:46:36 +00:00
predicate-entailment-passes.rs	Add tests	2024-10-24 09:46:36 +00:00
predicate-entailment-passes.stderr	Add tests	2024-10-24 09:46:36 +00:00
specializing-constness-2.rs
specializing-constness-2.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
specializing-constness.rs	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
specializing-constness.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
staged-api-user-crate.rs
staged-api-user-crate.stderr
staged-api.rs	Re-do recursive const stability checks	2024-10-25 20:31:40 +02:00
staged-api.stable.stderr	Re-do recursive const stability checks	2024-10-25 20:31:40 +02:00
staged-api.unstable.stderr	Re-do recursive const stability checks	2024-10-25 20:31:40 +02:00
static-const-trait-bound.rs
std-impl-gate.gated.stderr
std-impl-gate.rs
std-impl-gate.stock.stderr
super-traits-fail-2.nn.stderr
super-traits-fail-2.ny.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
super-traits-fail-2.rs	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
super-traits-fail-2.yn.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
super-traits-fail-2.yy.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
super-traits-fail-3.nn.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
super-traits-fail-3.ny.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
super-traits-fail-3.rs	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
super-traits-fail-3.yn.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
super-traits-fail.rs	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
super-traits-fail.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
super-traits.rs
syntax.rs
tilde-const-and-const-params.rs	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
tilde-const-and-const-params.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
tilde-const-assoc-fn-in-trait-impl.rs
tilde-const-in-struct-args.rs	Add tests	2024-10-24 09:46:36 +00:00
tilde-const-in-struct-args.stderr	Add tests	2024-10-24 09:46:36 +00:00
tilde-const-inherent-assoc-const-fn.rs
tilde-const-invalid-places.rs
tilde-const-invalid-places.stderr
tilde-const-syntax.rs
tilde-const-trait-assoc-tys.rs
tilde-twice.rs
tilde-twice.stderr
trait-default-body-stability.rs
trait-default-body-stability.stderr
trait-method-ptr-in-consts-ice.rs
trait-where-clause-const.rs	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
trait-where-clause-const.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00
trait-where-clause-run.rs
trait-where-clause-self-referential.rs
trait-where-clause.rs
trait-where-clause.stderr
unsatisfied-const-trait-bound.rs
unsatisfied-const-trait-bound.stderr	Implement const effect predicate in new solver	2024-10-24 09:46:36 +00:00