From 822762c966b0c8e85c0a552929a5a9c53bf93a97 Mon Sep 17 00:00:00 2001 From: Ralf Jung Date: Sat, 9 Nov 2024 22:19:35 +0100 Subject: [PATCH 1/2] require const_impl_trait gate for all conditional and trait const calls --- compiler/rustc_const_eval/messages.ftl | 4 + .../src/check_consts/check.rs | 87 ++++------- .../rustc_const_eval/src/check_consts/ops.rs | 39 +++-- compiler/rustc_const_eval/src/errors.rs | 10 ++ tests/ui/traits/const-traits/cross-crate.rs | 4 +- .../const-traits/cross-crate.stock.stderr | 28 +--- .../const-traits/cross-crate.stocknc.stderr | 53 +------ .../const-traits/staged-api-user-crate.rs | 3 +- .../const-traits/staged-api-user-crate.stderr | 24 +-- tests/ui/traits/const-traits/staged-api.rs | 50 +++---- .../const-traits/staged-api.stable.stderr | 89 ----------- .../ui/traits/const-traits/staged-api.stderr | 139 ++++++++++++++++++ .../const-traits/staged-api.unstable.stderr | 108 -------------- 13 files changed, 249 insertions(+), 389 deletions(-) delete mode 100644 tests/ui/traits/const-traits/staged-api.stable.stderr create mode 100644 tests/ui/traits/const-traits/staged-api.stderr delete mode 100644 tests/ui/traits/const-traits/staged-api.unstable.stderr diff --git a/compiler/rustc_const_eval/messages.ftl b/compiler/rustc_const_eval/messages.ftl index 826e34930ea..15027ae0c18 100644 --- a/compiler/rustc_const_eval/messages.ftl +++ b/compiler/rustc_const_eval/messages.ftl @@ -25,6 +25,10 @@ const_eval_closure_fndef_not_const = function defined here, but it is not `const` const_eval_closure_non_const = cannot call non-const closure in {const_eval_const_context}s + +const_eval_conditionally_const_call = + cannot call conditionally-const {$def_descr} `{$def_path_str}` in {const_eval_const_context}s + const_eval_consider_dereferencing = consider dereferencing here diff --git a/compiler/rustc_const_eval/src/check_consts/check.rs b/compiler/rustc_const_eval/src/check_consts/check.rs index aea3d5bd3e7..8cd0ecb3e4e 100644 --- a/compiler/rustc_const_eval/src/check_consts/check.rs +++ b/compiler/rustc_const_eval/src/check_consts/check.rs @@ -15,7 +15,7 @@ use rustc_middle::mir::*; use rustc_middle::span_bug; use rustc_middle::ty::adjustment::PointerCoercion; -use rustc_middle::ty::{self, Instance, InstanceKind, Ty, TypeVisitableExt}; +use rustc_middle::ty::{self, Ty, TypeVisitableExt}; use rustc_mir_dataflow::Analysis; use rustc_mir_dataflow::impls::MaybeStorageLive; use rustc_mir_dataflow::storage::always_storage_live_locals; @@ -361,31 +361,21 @@ fn place_may_escape(&mut self, place: &Place<'_>) -> bool { !is_transient } + /// Returns whether there are const-conditions. fn revalidate_conditional_constness( &mut self, callee: DefId, callee_args: ty::GenericArgsRef<'tcx>, - call_source: CallSource, call_span: Span, - ) { + ) -> bool { let tcx = self.tcx; if !tcx.is_conditionally_const(callee) { - return; + return false; } let const_conditions = tcx.const_conditions(callee).instantiate(tcx, callee_args); - // If there are any const conditions on this fn and `const_trait_impl` - // is not enabled, simply bail. We shouldn't be able to call conditionally - // const functions on stable. - if !const_conditions.is_empty() && !tcx.features().const_trait_impl() { - self.check_op(ops::FnCallNonConst { - callee, - args: callee_args, - span: call_span, - call_source, - feature: Some(sym::const_trait_impl), - }); - return; + if const_conditions.is_empty() { + return false; } let infcx = tcx.infer_ctxt().build(self.body.typing_mode(tcx)); @@ -421,6 +411,8 @@ fn revalidate_conditional_constness( tcx.dcx() .span_delayed_bug(call_span, "this should have reported a ~const error in HIR"); } + + true } } @@ -627,11 +619,11 @@ fn visit_terminator(&mut self, terminator: &Terminator<'tcx>, location: Location _ => unreachable!(), }; - let ConstCx { tcx, body, param_env, .. } = *self.ccx; + let ConstCx { tcx, body, .. } = *self.ccx; let fn_ty = func.ty(body, tcx); - let (mut callee, mut fn_args) = match *fn_ty.kind() { + let (callee, fn_args) = match *fn_ty.kind() { ty::FnDef(def_id, fn_args) => (def_id, fn_args), ty::FnPtr(..) => { @@ -645,57 +637,38 @@ fn visit_terminator(&mut self, terminator: &Terminator<'tcx>, location: Location } }; - self.revalidate_conditional_constness(callee, fn_args, call_source, *fn_span); + let has_const_conditions = + self.revalidate_conditional_constness(callee, fn_args, *fn_span); - let mut is_trait = false; // Attempting to call a trait method? if let Some(trait_did) = tcx.trait_of_item(callee) { + // We can't determine the actual callee here, so we have to do different checks + // than usual. + trace!("attempting to call a trait method"); - let trait_is_const = tcx.is_const_trait(trait_did); - // trait method calls are only permitted when `effects` is enabled. - // typeck ensures the conditions for calling a const trait method are met, - // so we only error if the trait isn't const. We try to resolve the trait - // into the concrete method, and uses that for const stability checks. - // FIXME(const_trait_impl) we might consider moving const stability checks - // to typeck as well. - if tcx.features().const_trait_impl() && trait_is_const { - // This skips the check below that ensures we only call `const fn`. - is_trait = true; - if let Ok(Some(instance)) = - Instance::try_resolve(tcx, param_env, callee, fn_args) - && let InstanceKind::Item(def) = instance.def - { - // Resolve a trait method call to its concrete implementation, which may be in a - // `const` trait impl. This is only used for the const stability check below, since - // we want to look at the concrete impl's stability. - fn_args = instance.args; - callee = def; - } + if trait_is_const { + // Trait calls are always conditionally-const. + self.check_op(ops::ConditionallyConstCall { callee, args: fn_args }); + // FIXME(const_trait_impl): do a more fine-grained check whether this + // particular trait can be const-stably called. } else { - // if the trait is const but the user has not enabled the feature(s), - // suggest them. - let feature = if trait_is_const { - Some(if tcx.features().const_trait_impl() { - sym::effects - } else { - sym::const_trait_impl - }) - } else { - None - }; + // Not even a const trait. self.check_op(ops::FnCallNonConst { callee, args: fn_args, span: *fn_span, call_source, - feature, }); - // If we allowed this, we're in miri-unleashed mode, so we might - // as well skip the remaining checks. - return; } + // That's all we can check here. + return; + } + + // Even if we know the callee, ensure we can use conditionally-const calls. + if has_const_conditions { + self.check_op(ops::ConditionallyConstCall { callee, args: fn_args }); } // At this point, we are calling a function, `callee`, whose `DefId` is known... @@ -783,14 +756,12 @@ fn visit_terminator(&mut self, terminator: &Terminator<'tcx>, location: Location return; } - // Trait functions are not `const fn` so we have to skip them here. - if !tcx.is_const_fn(callee) && !is_trait { + if !tcx.is_const_fn(callee) { self.check_op(ops::FnCallNonConst { callee, args: fn_args, span: *fn_span, call_source, - feature: None, }); // If we allowed this, we're in miri-unleashed mode, so we might // as well skip the remaining checks. diff --git a/compiler/rustc_const_eval/src/check_consts/ops.rs b/compiler/rustc_const_eval/src/check_consts/ops.rs index 2931159842f..5b745e6dffd 100644 --- a/compiler/rustc_const_eval/src/check_consts/ops.rs +++ b/compiler/rustc_const_eval/src/check_consts/ops.rs @@ -70,6 +70,34 @@ fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { } } +/// A call to a function that is in a trait, or has trait bounds that make it conditionally-const. +#[derive(Debug)] +pub(crate) struct ConditionallyConstCall<'tcx> { + pub callee: DefId, + pub args: GenericArgsRef<'tcx>, +} + +impl<'tcx> NonConstOp<'tcx> for ConditionallyConstCall<'tcx> { + fn status_in_item(&self, _ccx: &ConstCx<'_, 'tcx>) -> Status { + // We use the `const_trait_impl` gate for all conditionally-const calls. + Status::Unstable { + gate: sym::const_trait_impl, + safe_to_expose_on_stable: false, + // We don't want the "mark the callee as `#[rustc_const_stable_indirect]`" hint + is_function_call: false, + } + } + + fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { + ccx.dcx().create_err(errors::ConditionallyConstCall { + span, + def_path_str: ccx.tcx.def_path_str_with_args(self.callee, self.args), + def_descr: ccx.tcx.def_descr(self.callee), + kind: ccx.const_kind(), + }) + } +} + /// A function call where the callee is not marked as `const`. #[derive(Debug, Clone, Copy)] pub(crate) struct FnCallNonConst<'tcx> { @@ -77,7 +105,6 @@ pub(crate) struct FnCallNonConst<'tcx> { pub args: GenericArgsRef<'tcx>, pub span: Span, pub call_source: CallSource, - pub feature: Option, } impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { @@ -85,7 +112,7 @@ impl<'tcx> NonConstOp<'tcx> for FnCallNonConst<'tcx> { #[allow(rustc::diagnostic_outside_of_impl)] #[allow(rustc::untranslatable_diagnostic)] fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, _: Span) -> Diag<'tcx> { - let FnCallNonConst { callee, args, span, call_source, feature } = *self; + let FnCallNonConst { callee, args, span, call_source } = *self; let ConstCx { tcx, param_env, .. } = *ccx; let caller = ccx.def_id(); @@ -285,14 +312,6 @@ macro_rules! error { ccx.const_kind(), )); - if let Some(feature) = feature { - ccx.tcx.disabled_nightly_features( - &mut err, - Some(ccx.tcx.local_def_id_to_hir_id(caller)), - [(String::new(), feature)], - ); - } - if let ConstContext::Static(_) = ccx.const_kind() { err.note(fluent_generated::const_eval_lazy_lock); } diff --git a/compiler/rustc_const_eval/src/errors.rs b/compiler/rustc_const_eval/src/errors.rs index 14e8bebbb18..604e5ed61a3 100644 --- a/compiler/rustc_const_eval/src/errors.rs +++ b/compiler/rustc_const_eval/src/errors.rs @@ -176,6 +176,16 @@ pub(crate) struct NonConstFmtMacroCall { pub kind: ConstContext, } +#[derive(Diagnostic)] +#[diag(const_eval_conditionally_const_call)] +pub(crate) struct ConditionallyConstCall { + #[primary_span] + pub span: Span, + pub def_path_str: String, + pub def_descr: &'static str, + pub kind: ConstContext, +} + #[derive(Diagnostic)] #[diag(const_eval_non_const_fn_call, code = E0015)] pub(crate) struct NonConstFnCall { diff --git a/tests/ui/traits/const-traits/cross-crate.rs b/tests/ui/traits/const-traits/cross-crate.rs index 9558ec6164e..b07aa8944c0 100644 --- a/tests/ui/traits/const-traits/cross-crate.rs +++ b/tests/ui/traits/const-traits/cross-crate.rs @@ -18,11 +18,9 @@ const fn const_context() { #[cfg(any(stocknc, gatednc))] NonConst.func(); //[stocknc]~^ ERROR: cannot call - //[stocknc]~| ERROR: cannot call - //[gatednc]~^^^ ERROR: the trait bound + //[gatednc]~^^ ERROR: the trait bound Const.func(); //[stock,stocknc]~^ ERROR: cannot call - //[stock,stocknc]~| ERROR: cannot call } fn main() {} diff --git a/tests/ui/traits/const-traits/cross-crate.stock.stderr b/tests/ui/traits/const-traits/cross-crate.stock.stderr index b35891071b0..d26228f6958 100644 --- a/tests/ui/traits/const-traits/cross-crate.stock.stderr +++ b/tests/ui/traits/const-traits/cross-crate.stock.stderr @@ -1,28 +1,8 @@ -error[E0015]: cannot call non-const fn `::func` in constant functions - --> $DIR/cross-crate.rs:23:11 +error: cannot call conditionally-const method `::func` in constant functions + --> $DIR/cross-crate.rs:22:5 | LL | Const.func(); - | ^^^^^^ - | - = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants -help: add `#![feature(const_trait_impl)]` to the crate attributes to enable - | -LL + #![feature(const_trait_impl)] - | + | ^^^^^^^^^^^^ -error[E0015]: cannot call non-const fn `::func` in constant functions - --> $DIR/cross-crate.rs:23:11 - | -LL | Const.func(); - | ^^^^^^ - | - = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants - = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` -help: add `#![feature(const_trait_impl)]` to the crate attributes to enable - | -LL + #![feature(const_trait_impl)] - | +error: aborting due to 1 previous error -error: aborting due to 2 previous errors - -For more information about this error, try `rustc --explain E0015`. diff --git a/tests/ui/traits/const-traits/cross-crate.stocknc.stderr b/tests/ui/traits/const-traits/cross-crate.stocknc.stderr index 89de89159db..9b372860262 100644 --- a/tests/ui/traits/const-traits/cross-crate.stocknc.stderr +++ b/tests/ui/traits/const-traits/cross-crate.stocknc.stderr @@ -1,53 +1,14 @@ -error[E0015]: cannot call non-const fn `::func` in constant functions - --> $DIR/cross-crate.rs:19:14 +error: cannot call conditionally-const method `::func` in constant functions + --> $DIR/cross-crate.rs:19:5 | LL | NonConst.func(); - | ^^^^^^ - | - = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants -help: add `#![feature(const_trait_impl)]` to the crate attributes to enable - | -LL + #![feature(const_trait_impl)] - | + | ^^^^^^^^^^^^^^^ -error[E0015]: cannot call non-const fn `::func` in constant functions - --> $DIR/cross-crate.rs:19:14 - | -LL | NonConst.func(); - | ^^^^^^ - | - = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants - = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` -help: add `#![feature(const_trait_impl)]` to the crate attributes to enable - | -LL + #![feature(const_trait_impl)] - | - -error[E0015]: cannot call non-const fn `::func` in constant functions - --> $DIR/cross-crate.rs:23:11 +error: cannot call conditionally-const method `::func` in constant functions + --> $DIR/cross-crate.rs:22:5 | LL | Const.func(); - | ^^^^^^ - | - = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants -help: add `#![feature(const_trait_impl)]` to the crate attributes to enable - | -LL + #![feature(const_trait_impl)] - | + | ^^^^^^^^^^^^ -error[E0015]: cannot call non-const fn `::func` in constant functions - --> $DIR/cross-crate.rs:23:11 - | -LL | Const.func(); - | ^^^^^^ - | - = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants - = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` -help: add `#![feature(const_trait_impl)]` to the crate attributes to enable - | -LL + #![feature(const_trait_impl)] - | +error: aborting due to 2 previous errors -error: aborting due to 4 previous errors - -For more information about this error, try `rustc --explain E0015`. diff --git a/tests/ui/traits/const-traits/staged-api-user-crate.rs b/tests/ui/traits/const-traits/staged-api-user-crate.rs index c820d1ff47c..7587042cf27 100644 --- a/tests/ui/traits/const-traits/staged-api-user-crate.rs +++ b/tests/ui/traits/const-traits/staged-api-user-crate.rs @@ -10,8 +10,7 @@ fn non_const_context() { const fn stable_const_context() { Unstable::func(); - //~^ ERROR cannot call non-const fn `::func` in constant functions - //~| ERROR cannot call non-const fn `::func` in constant functions + //~^ ERROR cannot call conditionally-const associated function `::func` in constant functions } fn main() {} diff --git a/tests/ui/traits/const-traits/staged-api-user-crate.stderr b/tests/ui/traits/const-traits/staged-api-user-crate.stderr index 24cdb1d3d5a..2bce230ffdf 100644 --- a/tests/ui/traits/const-traits/staged-api-user-crate.stderr +++ b/tests/ui/traits/const-traits/staged-api-user-crate.stderr @@ -1,28 +1,8 @@ -error[E0015]: cannot call non-const fn `::func` in constant functions +error: cannot call conditionally-const associated function `::func` in constant functions --> $DIR/staged-api-user-crate.rs:12:5 | LL | Unstable::func(); | ^^^^^^^^^^^^^^^^ - | - = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants -help: add `#![feature(const_trait_impl)]` to the crate attributes to enable - | -LL + #![feature(const_trait_impl)] - | -error[E0015]: cannot call non-const fn `::func` in constant functions - --> $DIR/staged-api-user-crate.rs:12:5 - | -LL | Unstable::func(); - | ^^^^^^^^^^^^^^^^ - | - = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants - = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no` -help: add `#![feature(const_trait_impl)]` to the crate attributes to enable - | -LL + #![feature(const_trait_impl)] - | +error: aborting due to 1 previous error -error: aborting due to 2 previous errors - -For more information about this error, try `rustc --explain E0015`. diff --git a/tests/ui/traits/const-traits/staged-api.rs b/tests/ui/traits/const-traits/staged-api.rs index 401a81d8142..755a4e456bc 100644 --- a/tests/ui/traits/const-traits/staged-api.rs +++ b/tests/ui/traits/const-traits/staged-api.rs @@ -1,10 +1,11 @@ -//@ revisions: stable unstable +//! Checks whether we are properly enforcing recursive const stability for trait calls. //@ compile-flags: -Znext-solver -#![cfg_attr(unstable, feature(unstable))] // The feature from the ./auxiliary/staged-api.rs file. -#![cfg_attr(unstable, feature(local_feature))] +#![feature(unstable)] // The feature from the ./auxiliary/staged-api.rs file. +#![feature(local_feature)] #![feature(const_trait_impl)] #![feature(staged_api)] +#![feature(rustc_allow_const_fn_unstable)] #![stable(feature = "rust1", since = "1.0.0")] //@ aux-build: staged-api.rs @@ -16,13 +17,16 @@ pub struct Foo; #[stable(feature = "rust1", since = "1.0.0")] -#[cfg_attr(unstable, rustc_const_unstable(feature = "local_feature", issue = "none"))] -#[cfg_attr(stable, rustc_const_stable(feature = "local_feature", since = "1.0.0"))] +#[rustc_const_unstable(feature = "local_feature", issue = "none")] impl const MyTrait for Foo { - //[stable]~^ ERROR trait implementations cannot be const stable yet fn func() {} } +#[rustc_allow_const_fn_unstable(const_trait_impl)] +const fn conditionally_const() { + T::func(); +} + // Const stability has no impact on usage in non-const contexts. fn non_const_context() { Unstable::func(); @@ -32,43 +36,35 @@ fn non_const_context() { #[unstable(feature = "none", issue = "none")] const fn const_context() { Unstable::func(); - //[unstable]~^ ERROR cannot use `#[feature(unstable)]` - //[stable]~^^ ERROR not yet stable as a const fn + //~^ ERROR cannot use `#[feature(const_trait_impl)]` Foo::func(); - //[unstable]~^ ERROR cannot use `#[feature(local_feature)]` - //[stable]~^^ cannot be (indirectly) exposed to stable - // We get the error on `stable` since this is a trait function. + //~^ ERROR cannot use `#[feature(const_trait_impl)]` Unstable2::func(); - //~^ ERROR not yet stable as a const fn - // ^ fails, because the `unstable2` feature is not active + //~^ ERROR cannot use `#[feature(const_trait_impl)]` + conditionally_const::(); + //~^ ERROR cannot use `#[feature(const_trait_impl)]` } #[stable(feature = "rust1", since = "1.0.0")] -#[cfg_attr(unstable, rustc_const_unstable(feature = "local_feature", issue = "none"))] +#[rustc_const_unstable(feature = "local_feature", issue = "none")] pub const fn const_context_not_const_stable() { - //[stable]~^ ERROR function has missing const stability attribute Unstable::func(); - //[stable]~^ ERROR not yet stable as a const fn Foo::func(); - //[stable]~^ cannot be (indirectly) exposed to stable - // We get the error on `stable` since this is a trait function. Unstable2::func(); - //~^ ERROR not yet stable as a const fn - // ^ fails, because the `unstable2` feature is not active + conditionally_const::(); } #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "cheese", since = "1.0.0")] const fn stable_const_context() { Unstable::func(); - //[unstable]~^ ERROR cannot use `#[feature(unstable)]` - //[stable]~^^ ERROR not yet stable as a const fn + //~^ ERROR cannot use `#[feature(const_trait_impl)]` Foo::func(); - //[unstable]~^ ERROR cannot use `#[feature(local_feature)]` - //[stable]~^^ cannot be (indirectly) exposed to stable - // We get the error on `stable` since this is a trait function. - const_context_not_const_stable() - //[unstable]~^ ERROR cannot use `#[feature(local_feature)]` + //~^ ERROR cannot use `#[feature(const_trait_impl)]` + const_context_not_const_stable(); + //~^ ERROR cannot use `#[feature(local_feature)]` + conditionally_const::(); + //~^ ERROR cannot use `#[feature(const_trait_impl)]` } fn main() {} diff --git a/tests/ui/traits/const-traits/staged-api.stable.stderr b/tests/ui/traits/const-traits/staged-api.stable.stderr deleted file mode 100644 index 8f491b2f182..00000000000 --- a/tests/ui/traits/const-traits/staged-api.stable.stderr +++ /dev/null @@ -1,89 +0,0 @@ -error: trait implementations cannot be const stable yet - --> $DIR/staged-api.rs:21:1 - | -LL | / impl const MyTrait for Foo { -LL | | -LL | | fn func() {} -LL | | } - | |_^ - | - = note: see issue #67792 for more information - -error: function has missing const stability attribute - --> $DIR/staged-api.rs:48:1 - | -LL | / pub const fn const_context_not_const_stable() { -LL | | -LL | | Unstable::func(); -LL | | -... | -LL | | // ^ fails, because the `unstable2` feature is not active -LL | | } - | |_^ - -error: `::func` is not yet stable as a const fn - --> $DIR/staged-api.rs:34:5 - | -LL | Unstable::func(); - | ^^^^^^^^^^^^^^^^ - | - = help: add `#![feature(unstable)]` to the crate attributes to enable - -error: `::func` cannot be (indirectly) exposed to stable - --> $DIR/staged-api.rs:37:5 - | -LL | Foo::func(); - | ^^^^^^^^^^^ - | - = help: either mark the callee as `#[rustc_const_stable_indirect]`, or the caller as `#[rustc_const_unstable]` - -error: `::func` is not yet stable as a const fn - --> $DIR/staged-api.rs:41:5 - | -LL | Unstable2::func(); - | ^^^^^^^^^^^^^^^^^ - | - = help: add `#![feature(unstable2)]` to the crate attributes to enable - -error: `::func` is not yet stable as a const fn - --> $DIR/staged-api.rs:50:5 - | -LL | Unstable::func(); - | ^^^^^^^^^^^^^^^^ - | - = help: add `#![feature(unstable)]` to the crate attributes to enable - -error: `::func` cannot be (indirectly) exposed to stable - --> $DIR/staged-api.rs:52:5 - | -LL | Foo::func(); - | ^^^^^^^^^^^ - | - = help: either mark the callee as `#[rustc_const_stable_indirect]`, or the caller as `#[rustc_const_unstable]` - -error: `::func` is not yet stable as a const fn - --> $DIR/staged-api.rs:55:5 - | -LL | Unstable2::func(); - | ^^^^^^^^^^^^^^^^^ - | - = help: add `#![feature(unstable2)]` to the crate attributes to enable - -error: `::func` is not yet stable as a const fn - --> $DIR/staged-api.rs:63:5 - | -LL | Unstable::func(); - | ^^^^^^^^^^^^^^^^ - | - = help: add `#![feature(unstable)]` to the crate attributes to enable - -error: `::func` cannot be (indirectly) exposed to stable - --> $DIR/staged-api.rs:66:5 - | -LL | Foo::func(); - | ^^^^^^^^^^^ - | - = help: either mark the callee as `#[rustc_const_stable_indirect]`, or the caller as `#[rustc_const_unstable]` - -error: aborting due to 10 previous errors - diff --git a/tests/ui/traits/const-traits/staged-api.stderr b/tests/ui/traits/const-traits/staged-api.stderr new file mode 100644 index 00000000000..29aafa4e0f3 --- /dev/null +++ b/tests/ui/traits/const-traits/staged-api.stderr @@ -0,0 +1,139 @@ +error: const function that might be (indirectly) exposed to stable cannot use `#[feature(const_trait_impl)]` + --> $DIR/staged-api.rs:38:5 + | +LL | Unstable::func(); + | ^^^^^^^^^^^^^^^^ + | +help: if the function is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) + | +LL + #[rustc_const_unstable(feature = "...", issue = "...")] +LL | const fn const_context() { + | +help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) + | +LL + #[rustc_allow_const_fn_unstable(const_trait_impl)] +LL | const fn const_context() { + | + +error: const function that might be (indirectly) exposed to stable cannot use `#[feature(const_trait_impl)]` + --> $DIR/staged-api.rs:40:5 + | +LL | Foo::func(); + | ^^^^^^^^^^^ + | +help: if the function is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) + | +LL + #[rustc_const_unstable(feature = "...", issue = "...")] +LL | const fn const_context() { + | +help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) + | +LL + #[rustc_allow_const_fn_unstable(const_trait_impl)] +LL | const fn const_context() { + | + +error: const function that might be (indirectly) exposed to stable cannot use `#[feature(const_trait_impl)]` + --> $DIR/staged-api.rs:42:5 + | +LL | Unstable2::func(); + | ^^^^^^^^^^^^^^^^^ + | +help: if the function is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) + | +LL + #[rustc_const_unstable(feature = "...", issue = "...")] +LL | const fn const_context() { + | +help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) + | +LL + #[rustc_allow_const_fn_unstable(const_trait_impl)] +LL | const fn const_context() { + | + +error: const function that might be (indirectly) exposed to stable cannot use `#[feature(const_trait_impl)]` + --> $DIR/staged-api.rs:44:5 + | +LL | conditionally_const::(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: if the function is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) + | +LL + #[rustc_const_unstable(feature = "...", issue = "...")] +LL | const fn const_context() { + | +help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) + | +LL + #[rustc_allow_const_fn_unstable(const_trait_impl)] +LL | const fn const_context() { + | + +error: const function that might be (indirectly) exposed to stable cannot use `#[feature(const_trait_impl)]` + --> $DIR/staged-api.rs:60:5 + | +LL | Unstable::func(); + | ^^^^^^^^^^^^^^^^ + | +help: if the function is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) + | +LL + #[rustc_const_unstable(feature = "...", issue = "...")] +LL | const fn stable_const_context() { + | +help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) + | +LL + #[rustc_allow_const_fn_unstable(const_trait_impl)] +LL | const fn stable_const_context() { + | + +error: const function that might be (indirectly) exposed to stable cannot use `#[feature(const_trait_impl)]` + --> $DIR/staged-api.rs:62:5 + | +LL | Foo::func(); + | ^^^^^^^^^^^ + | +help: if the function is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) + | +LL + #[rustc_const_unstable(feature = "...", issue = "...")] +LL | const fn stable_const_context() { + | +help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) + | +LL + #[rustc_allow_const_fn_unstable(const_trait_impl)] +LL | const fn stable_const_context() { + | + +error: const function that might be (indirectly) exposed to stable cannot use `#[feature(local_feature)]` + --> $DIR/staged-api.rs:64:5 + | +LL | const_context_not_const_stable(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | + = help: mark the callee as `#[rustc_const_stable_indirect]` if it does not itself require any unsafe features +help: if the caller is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) + | +LL + #[rustc_const_unstable(feature = "...", issue = "...")] +LL | const fn stable_const_context() { + | +help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) + | +LL + #[rustc_allow_const_fn_unstable(local_feature)] +LL | const fn stable_const_context() { + | + +error: const function that might be (indirectly) exposed to stable cannot use `#[feature(const_trait_impl)]` + --> $DIR/staged-api.rs:66:5 + | +LL | conditionally_const::(); + | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + | +help: if the function is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) + | +LL + #[rustc_const_unstable(feature = "...", issue = "...")] +LL | const fn stable_const_context() { + | +help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) + | +LL + #[rustc_allow_const_fn_unstable(const_trait_impl)] +LL | const fn stable_const_context() { + | + +error: aborting due to 8 previous errors + diff --git a/tests/ui/traits/const-traits/staged-api.unstable.stderr b/tests/ui/traits/const-traits/staged-api.unstable.stderr deleted file mode 100644 index 76275452e90..00000000000 --- a/tests/ui/traits/const-traits/staged-api.unstable.stderr +++ /dev/null @@ -1,108 +0,0 @@ -error: const function that might be (indirectly) exposed to stable cannot use `#[feature(unstable)]` - --> $DIR/staged-api.rs:34:5 - | -LL | Unstable::func(); - | ^^^^^^^^^^^^^^^^ - | - = help: mark the callee as `#[rustc_const_stable_indirect]` if it does not itself require any unsafe features -help: if the caller is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) - | -LL + #[rustc_const_unstable(feature = "...", issue = "...")] -LL | const fn const_context() { - | -help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) - | -LL + #[rustc_allow_const_fn_unstable(unstable)] -LL | const fn const_context() { - | - -error: const function that might be (indirectly) exposed to stable cannot use `#[feature(local_feature)]` - --> $DIR/staged-api.rs:37:5 - | -LL | Foo::func(); - | ^^^^^^^^^^^ - | - = help: mark the callee as `#[rustc_const_stable_indirect]` if it does not itself require any unsafe features -help: if the caller is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) - | -LL + #[rustc_const_unstable(feature = "...", issue = "...")] -LL | const fn const_context() { - | -help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) - | -LL + #[rustc_allow_const_fn_unstable(local_feature)] -LL | const fn const_context() { - | - -error: `::func` is not yet stable as a const fn - --> $DIR/staged-api.rs:41:5 - | -LL | Unstable2::func(); - | ^^^^^^^^^^^^^^^^^ - | - = help: add `#![feature(unstable2)]` to the crate attributes to enable - -error: `::func` is not yet stable as a const fn - --> $DIR/staged-api.rs:55:5 - | -LL | Unstable2::func(); - | ^^^^^^^^^^^^^^^^^ - | - = help: add `#![feature(unstable2)]` to the crate attributes to enable - -error: const function that might be (indirectly) exposed to stable cannot use `#[feature(unstable)]` - --> $DIR/staged-api.rs:63:5 - | -LL | Unstable::func(); - | ^^^^^^^^^^^^^^^^ - | - = help: mark the callee as `#[rustc_const_stable_indirect]` if it does not itself require any unsafe features -help: if the caller is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) - | -LL + #[rustc_const_unstable(feature = "...", issue = "...")] -LL | const fn stable_const_context() { - | -help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) - | -LL + #[rustc_allow_const_fn_unstable(unstable)] -LL | const fn stable_const_context() { - | - -error: const function that might be (indirectly) exposed to stable cannot use `#[feature(local_feature)]` - --> $DIR/staged-api.rs:66:5 - | -LL | Foo::func(); - | ^^^^^^^^^^^ - | - = help: mark the callee as `#[rustc_const_stable_indirect]` if it does not itself require any unsafe features -help: if the caller is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) - | -LL + #[rustc_const_unstable(feature = "...", issue = "...")] -LL | const fn stable_const_context() { - | -help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) - | -LL + #[rustc_allow_const_fn_unstable(local_feature)] -LL | const fn stable_const_context() { - | - -error: const function that might be (indirectly) exposed to stable cannot use `#[feature(local_feature)]` - --> $DIR/staged-api.rs:70:5 - | -LL | const_context_not_const_stable() - | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ - | - = help: mark the callee as `#[rustc_const_stable_indirect]` if it does not itself require any unsafe features -help: if the caller is not (yet) meant to be exposed to stable, add `#[rustc_const_unstable]` (this is what you probably want to do) - | -LL + #[rustc_const_unstable(feature = "...", issue = "...")] -LL | const fn stable_const_context() { - | -help: otherwise, as a last resort `#[rustc_allow_const_fn_unstable]` can be used to bypass stability checks (this requires team approval) - | -LL + #[rustc_allow_const_fn_unstable(local_feature)] -LL | const fn stable_const_context() { - | - -error: aborting due to 7 previous errors - From f235b6f9c6788e213b6365103cfa9c6c798fe659 Mon Sep 17 00:00:00 2001 From: Ralf Jung Date: Sat, 9 Nov 2024 23:32:06 +0100 Subject: [PATCH 2/2] give a hint which feature is missing --- .../rustc_const_eval/src/check_consts/ops.rs | 26 ++++++++----------- compiler/rustc_session/src/parse.rs | 1 + compiler/rustc_session/src/session.rs | 1 + .../const-traits/cross-crate.stock.stderr | 7 ++++- .../const-traits/cross-crate.stocknc.stderr | 13 ++++++++-- .../const-traits/staged-api-user-crate.stderr | 7 ++++- 6 files changed, 36 insertions(+), 19 deletions(-) diff --git a/compiler/rustc_const_eval/src/check_consts/ops.rs b/compiler/rustc_const_eval/src/check_consts/ops.rs index 5b745e6dffd..036ca763280 100644 --- a/compiler/rustc_const_eval/src/check_consts/ops.rs +++ b/compiler/rustc_const_eval/src/check_consts/ops.rs @@ -89,12 +89,15 @@ fn status_in_item(&self, _ccx: &ConstCx<'_, 'tcx>) -> Status { } fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { - ccx.dcx().create_err(errors::ConditionallyConstCall { - span, - def_path_str: ccx.tcx.def_path_str_with_args(self.callee, self.args), - def_descr: ccx.tcx.def_descr(self.callee), - kind: ccx.const_kind(), - }) + ccx.tcx.sess.create_feature_err( + errors::ConditionallyConstCall { + span, + def_path_str: ccx.tcx.def_path_str_with_args(self.callee, self.args), + def_descr: ccx.tcx.def_descr(self.callee), + kind: ccx.const_kind(), + }, + sym::const_trait_impl, + ) } } @@ -417,15 +420,8 @@ fn status_in_item(&self, _: &ConstCx<'_, 'tcx>) -> Status { fn build_error(&self, ccx: &ConstCx<'_, 'tcx>, span: Span) -> Diag<'tcx> { let msg = format!("{:#}s are not allowed in {}s", self.0, ccx.const_kind()); - if let hir::CoroutineKind::Desugared( - hir::CoroutineDesugaring::Async, - hir::CoroutineSource::Block, - ) = self.0 - { - ccx.tcx.sess.create_feature_err( - errors::UnallowedOpInConstContext { span, msg }, - sym::const_async_blocks, - ) + if let Status::Unstable { gate, .. } = self.status_in_item(ccx) { + ccx.tcx.sess.create_feature_err(errors::UnallowedOpInConstContext { span, msg }, gate) } else { ccx.dcx().create_err(errors::UnallowedOpInConstContext { span, msg }) } diff --git a/compiler/rustc_session/src/parse.rs b/compiler/rustc_session/src/parse.rs index f20ae85b8e8..21c11655110 100644 --- a/compiler/rustc_session/src/parse.rs +++ b/compiler/rustc_session/src/parse.rs @@ -155,6 +155,7 @@ pub fn feature_warn_issue( } /// Adds the diagnostics for a feature to an existing error. +/// Must be a language feature! pub fn add_feature_diagnostics( err: &mut Diag<'_, G>, sess: &Session, diff --git a/compiler/rustc_session/src/session.rs b/compiler/rustc_session/src/session.rs index 470e372ee48..9d9434a7776 100644 --- a/compiler/rustc_session/src/session.rs +++ b/compiler/rustc_session/src/session.rs @@ -300,6 +300,7 @@ pub fn is_test_crate(&self) -> bool { self.opts.test } + /// `feature` must be a language feature. #[track_caller] pub fn create_feature_err<'a>(&'a self, err: impl Diagnostic<'a>, feature: Symbol) -> Diag<'a> { let mut err = self.dcx().create_err(err); diff --git a/tests/ui/traits/const-traits/cross-crate.stock.stderr b/tests/ui/traits/const-traits/cross-crate.stock.stderr index d26228f6958..09bf9c023c8 100644 --- a/tests/ui/traits/const-traits/cross-crate.stock.stderr +++ b/tests/ui/traits/const-traits/cross-crate.stock.stderr @@ -1,8 +1,13 @@ -error: cannot call conditionally-const method `::func` in constant functions +error[E0658]: cannot call conditionally-const method `::func` in constant functions --> $DIR/cross-crate.rs:22:5 | LL | Const.func(); | ^^^^^^^^^^^^ + | + = note: see issue #67792 for more information + = help: add `#![feature(const_trait_impl)]` to the crate attributes to enable + = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date error: aborting due to 1 previous error +For more information about this error, try `rustc --explain E0658`. diff --git a/tests/ui/traits/const-traits/cross-crate.stocknc.stderr b/tests/ui/traits/const-traits/cross-crate.stocknc.stderr index 9b372860262..e52e5609b01 100644 --- a/tests/ui/traits/const-traits/cross-crate.stocknc.stderr +++ b/tests/ui/traits/const-traits/cross-crate.stocknc.stderr @@ -1,14 +1,23 @@ -error: cannot call conditionally-const method `::func` in constant functions +error[E0658]: cannot call conditionally-const method `::func` in constant functions --> $DIR/cross-crate.rs:19:5 | LL | NonConst.func(); | ^^^^^^^^^^^^^^^ + | + = note: see issue #67792 for more information + = help: add `#![feature(const_trait_impl)]` to the crate attributes to enable + = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date -error: cannot call conditionally-const method `::func` in constant functions +error[E0658]: cannot call conditionally-const method `::func` in constant functions --> $DIR/cross-crate.rs:22:5 | LL | Const.func(); | ^^^^^^^^^^^^ + | + = note: see issue #67792 for more information + = help: add `#![feature(const_trait_impl)]` to the crate attributes to enable + = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date error: aborting due to 2 previous errors +For more information about this error, try `rustc --explain E0658`. diff --git a/tests/ui/traits/const-traits/staged-api-user-crate.stderr b/tests/ui/traits/const-traits/staged-api-user-crate.stderr index 2bce230ffdf..bf7466b8e16 100644 --- a/tests/ui/traits/const-traits/staged-api-user-crate.stderr +++ b/tests/ui/traits/const-traits/staged-api-user-crate.stderr @@ -1,8 +1,13 @@ -error: cannot call conditionally-const associated function `::func` in constant functions +error[E0658]: cannot call conditionally-const associated function `::func` in constant functions --> $DIR/staged-api-user-crate.rs:12:5 | LL | Unstable::func(); | ^^^^^^^^^^^^^^^^ + | + = note: see issue #67792 for more information + = help: add `#![feature(const_trait_impl)]` to the crate attributes to enable + = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date error: aborting due to 1 previous error +For more information about this error, try `rustc --explain E0658`.