Rollup merge of #126552 - fee1-dead-contrib:rmfx, r=compiler-errors

Remove use of const traits (and `feature(effects)`) from stdlib

The current uses are already unsound because they are using non-const impls in const contexts. We can reintroduce them by reverting the commit in this PR, after #120639 lands.

Also, make `effects` an incomplete feature.

cc `@rust-lang/project-const-traits`
r? `@compiler-errors`

compiler/rustc_feature/src/unstable.rs

@@ -449,7 +449,7 @@ pub fn internal(&self, feature: Symbol) -> bool {
     /// Allows `dyn* Trait` objects.
     (incomplete, dyn_star, "1.65.0", Some(102425)),
     /// Uses generic effect parameters for ~const bounds
-    (unstable, effects, "1.72.0", Some(102090)),
+    (incomplete, effects, "1.72.0", Some(102090)),
     /// Allows exhaustive pattern matching on types that contain uninhabited types.
     (unstable, exhaustive_patterns, "1.13.0", Some(51085)),
     /// Allows explicit tail calls via `become` expression.

compiler/rustc_hir_analysis/src/check/intrinsic.rs

@@ -429,17 +429,17 @@ pub fn check_intrinsic_type(
 
             sym::ptr_guaranteed_cmp => (
                 1,
-                1,
+                0,
                 vec![Ty::new_imm_ptr(tcx, param(0)), Ty::new_imm_ptr(tcx, param(0))],
                 tcx.types.u8,
             ),
 
             sym::const_allocate => {
-                (0, 1, vec![tcx.types.usize, tcx.types.usize], Ty::new_mut_ptr(tcx, tcx.types.u8))
+                (0, 0, vec![tcx.types.usize, tcx.types.usize], Ty::new_mut_ptr(tcx, tcx.types.u8))
             }
             sym::const_deallocate => (
                 0,
-                1,
+                0,
                 vec![Ty::new_mut_ptr(tcx, tcx.types.u8), tcx.types.usize, tcx.types.usize],
                 tcx.types.unit,
             ),
@@ -478,16 +478,16 @@ pub fn check_intrinsic_type(
             | sym::frem_algebraic => (1, 0, vec![param(0), param(0)], param(0)),
             sym::float_to_int_unchecked => (2, 0, vec![param(0)], param(1)),
 
-            sym::assume => (0, 1, vec![tcx.types.bool], tcx.types.unit),
-            sym::likely => (0, 1, vec![tcx.types.bool], tcx.types.bool),
-            sym::unlikely => (0, 1, vec![tcx.types.bool], tcx.types.bool),
+            sym::assume => (0, 0, vec![tcx.types.bool], tcx.types.unit),
+            sym::likely => (0, 0, vec![tcx.types.bool], tcx.types.bool),
+            sym::unlikely => (0, 0, vec![tcx.types.bool], tcx.types.bool),
 
             sym::read_via_copy => (1, 0, vec![Ty::new_imm_ptr(tcx, param(0))], param(0)),
             sym::write_via_move => {
                 (1, 0, vec![Ty::new_mut_ptr(tcx, param(0)), param(0)], tcx.types.unit)
             }
 
-            sym::typed_swap => (1, 1, vec![Ty::new_mut_ptr(tcx, param(0)); 2], tcx.types.unit),
+            sym::typed_swap => (1, 0, vec![Ty::new_mut_ptr(tcx, param(0)); 2], tcx.types.unit),
 
             sym::discriminant_value => {
                 let assoc_items = tcx.associated_item_def_ids(
@@ -566,9 +566,9 @@ pub fn check_intrinsic_type(
 
             sym::black_box => (1, 0, vec![param(0)], param(0)),
 
-            sym::is_val_statically_known => (1, 1, vec![param(0)], tcx.types.bool),
+            sym::is_val_statically_known => (1, 0, vec![param(0)], tcx.types.bool),
 
-            sym::const_eval_select => (4, 1, vec![param(0), param(1), param(2)], param(3)),
+            sym::const_eval_select => (4, 0, vec![param(0), param(1), param(2)], param(3)),
 
             sym::vtable_size | sym::vtable_align => {
                 (0, 0, vec![Ty::new_imm_ptr(tcx, tcx.types.unit)], tcx.types.usize)
@@ -576,10 +576,10 @@ pub fn check_intrinsic_type(
 
             // This type check is not particularly useful, but the `where` bounds
             // on the definition in `core` do the heavy lifting for checking it.
-            sym::aggregate_raw_ptr => (3, 1, vec![param(1), param(2)], param(0)),
-            sym::ptr_metadata => (2, 1, vec![Ty::new_imm_ptr(tcx, param(0))], param(1)),
+            sym::aggregate_raw_ptr => (3, 0, vec![param(1), param(2)], param(0)),
+            sym::ptr_metadata => (2, 0, vec![Ty::new_imm_ptr(tcx, param(0))], param(1)),
 
-            sym::ub_checks => (0, 1, Vec::new(), tcx.types.bool),
+            sym::ub_checks => (0, 0, Vec::new(), tcx.types.bool),
 
             sym::simd_eq
             | sym::simd_ne

library/alloc/src/lib.rs

@@ -175,7 +175,6 @@
 #![feature(const_mut_refs)]
 #![feature(const_precise_live_drops)]
 #![feature(const_ptr_write)]
-#![feature(const_trait_impl)]
 #![feature(const_try)]
 #![feature(decl_macro)]
 #![feature(dropck_eyepatch)]

library/core/src/cmp.rs

@@ -245,7 +245,6 @@
     append_const_msg
 )]
 #[rustc_diagnostic_item = "PartialEq"]
-#[const_trait]
 pub trait PartialEq<Rhs: ?Sized = Self> {
     /// This method tests for `self` and `other` values to be equal, and is used
     /// by `==`.
@@ -1475,8 +1474,7 @@ mod impls {
     macro_rules! partial_eq_impl {
         ($($t:ty)*) => ($(
             #[stable(feature = "rust1", since = "1.0.0")]
-            #[rustc_const_unstable(feature = "const_cmp", issue = "92391")]
-            impl const PartialEq for $t {
+            impl PartialEq for $t {
                 #[inline]
                 fn eq(&self, other: &$t) -> bool { (*self) == (*other) }
                 #[inline]

library/core/src/escape.rs

@@ -60,7 +60,7 @@
 const fn escape_unicode<const N: usize>(c: char) -> ([ascii::Char; N], Range<u8>) {
     const { assert!(N >= 10 && N < u8::MAX as usize) };
 
-    let c = u32::from(c);
+    let c = c as u32;
 
     // OR-ing `1` ensures that for `c == 0` the code computes that
     // one digit should be printed.

library/core/src/ffi/c_str.rs

@@ -515,7 +515,10 @@ pub const fn as_ptr(&self) -> *const c_char {
     #[inline]
     #[must_use]
     const fn as_non_null_ptr(&self) -> NonNull<c_char> {
-        NonNull::from(&self.inner).as_non_null_ptr()
+        // FIXME(effects) replace with `NonNull::from`
+        // SAFETY: a reference is never null
+        unsafe { NonNull::new_unchecked(&self.inner as *const [c_char] as *mut [c_char]) }
+            .as_non_null_ptr()
     }
 
     /// Returns the length of `self`. Like C's `strlen`, this does not include the nul terminator.

library/core/src/lib.rs

@@ -200,6 +200,7 @@
 // Language features:
 // tidy-alphabetical-start
 #![cfg_attr(bootstrap, feature(c_unwind))]
+#![cfg_attr(bootstrap, feature(effects))]
 #![feature(abi_unadjusted)]
 #![feature(adt_const_params)]
 #![feature(allow_internal_unsafe)]
@@ -214,13 +215,11 @@
 #![feature(const_mut_refs)]
 #![feature(const_precise_live_drops)]
 #![feature(const_refs_to_cell)]
-#![feature(const_trait_impl)]
 #![feature(decl_macro)]
 #![feature(deprecated_suggestion)]
 #![feature(doc_cfg)]
 #![feature(doc_cfg_hide)]
 #![feature(doc_notable_trait)]
-#![feature(effects)]
 #![feature(extern_types)]
 #![feature(f128)]
 #![feature(f16)]

library/core/src/marker.rs

@@ -944,7 +944,6 @@ impl !Unpin for PhantomPinned {}
 #[lang = "destruct"]
 #[rustc_on_unimplemented(message = "can't drop `{Self}`", append_const_msg)]
 #[rustc_deny_explicit_impl(implement_via_object = false)]
-#[const_trait]
 pub trait Destruct {}
 
 /// A marker for tuple types.

library/core/src/num/nonzero.rs

@@ -33,7 +33,6 @@
     reason = "implementation detail which may disappear or be replaced at any time",
     issue = "none"
 )]
-#[const_trait]
 pub unsafe trait ZeroablePrimitive: Sized + Copy + private::Sealed {
     #[doc(hidden)]
     type NonZeroInner: Sized + Copy;
@@ -47,7 +46,6 @@ mod private {
                 reason = "implementation detail which may disappear or be replaced at any time",
                 issue = "none"
             )]
-            #[const_trait]
             pub trait Sealed {}
 
             $(
@@ -70,14 +68,14 @@ pub trait Sealed {}
                 reason = "implementation detail which may disappear or be replaced at any time",
                 issue = "none"
             )]
-            impl const private::Sealed for $primitive {}
+            impl private::Sealed for $primitive {}
 
             #[unstable(
                 feature = "nonzero_internals",
                 reason = "implementation detail which may disappear or be replaced at any time",
                 issue = "none"
             )]
-            unsafe impl const ZeroablePrimitive for $primitive {
+            unsafe impl ZeroablePrimitive for $primitive {
                 type NonZeroInner = private::$NonZeroInner;
             }
         )+

library/core/src/ops/arith.rs

@@ -73,7 +73,6 @@
     append_const_msg
 )]
 #[doc(alias = "+")]
-#[const_trait]
 pub trait Add<Rhs = Self> {
     /// The resulting type after applying the `+` operator.
     #[stable(feature = "rust1", since = "1.0.0")]
@@ -95,8 +94,7 @@ pub trait Add<Rhs = Self> {
 macro_rules! add_impl {
     ($($t:ty)*) => ($(
         #[stable(feature = "rust1", since = "1.0.0")]
-        #[rustc_const_unstable(feature = "const_ops", issue = "90080")]
-        impl const Add for $t {
+        impl Add for $t {
             type Output = $t;
 
             #[inline]

library/core/src/task/wake.rs

@@ -282,7 +282,7 @@ pub const fn local_waker(&self) -> &'a LocalWaker {
     pub const fn ext(&mut self) -> &mut dyn Any {
         // FIXME: this field makes Context extra-weird about unwind safety
         // can we justify AssertUnwindSafe if we stabilize this? do we care?
-        match &mut *self.ext {
+        match &mut self.ext.0 {
             ExtData::Some(data) => *data,
             ExtData::None(unit) => unit,
         }
@@ -356,7 +356,7 @@ pub const fn from_waker(waker: &'a Waker) -> Self {
     #[rustc_const_unstable(feature = "const_waker", issue = "102012")]
     #[unstable(feature = "context_ext", issue = "123392")]
     pub const fn from(cx: &'a mut Context<'_>) -> Self {
-        let ext = match &mut *cx.ext {
+        let ext = match &mut cx.ext.0 {
             ExtData::Some(ext) => ExtData::Some(*ext),
             ExtData::None(()) => ExtData::None(()),
         };

library/std/src/lib.rs

@@ -284,7 +284,6 @@
 #![feature(cfi_encoding)]
 #![feature(concat_idents)]
 #![feature(const_mut_refs)]
-#![feature(const_trait_impl)]
 #![feature(decl_macro)]
 #![feature(deprecated_suggestion)]
 #![feature(doc_cfg)]

src/doc/unstable-book/src/language-features/intrinsics.md

@@ -18,7 +18,7 @@ All intrinsic fallback bodies are automatically made cross-crate inlineable (lik
 by the codegen backend, but not the MIR inliner.
 
 ```rust
-#![feature(rustc_attrs, effects)]
+#![feature(rustc_attrs)]
 #![allow(internal_features)]
 
 #[rustc_intrinsic]
@@ -28,7 +28,7 @@ const unsafe fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
 Since these are just regular functions, it is perfectly ok to create the intrinsic twice:
 
 ```rust
-#![feature(rustc_attrs, effects)]
+#![feature(rustc_attrs)]
 #![allow(internal_features)]
 
 #[rustc_intrinsic]

src/tools/miri/tests/fail/intrinsic_fallback_is_spec.rs

@@ -1,4 +1,4 @@
-#![feature(rustc_attrs, effects)]
+#![feature(rustc_attrs)]
 
 #[rustc_intrinsic]
 #[rustc_nounwind]

tests/crashes/120503.rs

@@ -1,10 +0,0 @@
-//@ known-bug: #120503
-#![feature(effects)]
-
-trait MyTrait {}
-
-impl MyTrait for i32 {
-    async const fn bar(&self) {
-        main8().await;
-    }
-}

tests/crashes/121536.rs

@@ -1,20 +0,0 @@
-//@ known-bug: #121536
-#![feature(effects)]
-
-#[derive(Debug, Clone, Copy)]
-pub struct Vec3 {
-    pub x: f32,
-    pub y: f32,
-    pub z: f32,
-}
-
-impl std::ops::Add<Vec3> for Vec3 {
-    type Output = Vec3;
-    const fn add(self, b: Vec3) -> Self::Output {
-        Vec3 {
-            x: self.x + b.x,
-            y: self.y + b.y,
-            z: self.z + b.z,
-        }
-    }
-}

tests/rustdoc/const-effect-param.rs

@@ -2,6 +2,7 @@
 
 #![crate_name = "foo"]
 #![feature(effects, const_trait_impl)]
+#![allow(incomplete_features)]
 
 #[const_trait]
 pub trait Tr {

tests/rustdoc/const-fn-effects.rs

@@ -1,5 +1,6 @@
 #![crate_name = "foo"]
 #![feature(effects)]
+#![allow(incomplete_features)]
 
 // @has foo/fn.bar.html
 // @has - '//pre[@class="rust item-decl"]' 'pub const fn bar() -> '

tests/rustdoc/rfc-2632-const-trait-impl.rs

@@ -7,6 +7,7 @@
 // not remove this test.
 //
 // FIXME(effects) add `const_trait` to `Fn` so we use `~const`
+// FIXME(effects) restore `const_trait` to `Destruct`
 #![feature(const_trait_impl)]
 #![crate_name = "foo"]
 
@@ -24,9 +25,9 @@ pub trait Tr<T> {
     // @has - '//section[@id="method.a"]/h4[@class="code-header"]/a[@class="trait"]' 'Fn'
     // @!has - '//section[@id="method.a"]/h4[@class="code-header"]/span[@class="where"]' '~const'
     // @has - '//section[@id="method.a"]/h4[@class="code-header"]/div[@class="where"]' ': Fn'
-    fn a<A: /* ~const */ Fn() + ~const Destruct>()
+    fn a<A: /* ~const */ Fn() /* + ~const Destruct */>()
     where
-        Option<A>: /* ~const */ Fn() + ~const Destruct,
+        Option<A>: /* ~const */ Fn() /* + ~const Destruct */,
     {
     }
 }
@@ -36,13 +37,13 @@ fn a<A: /* ~const */ Fn() + ~const Destruct>()
 // @has - '//section[@id="impl-Tr%3CT%3E-for-T"]/h3[@class="code-header"]/a[@class="trait"]' 'Fn'
 // @!has - '//section[@id="impl-Tr%3CT%3E-for-T"]/h3[@class="code-header"]/span[@class="where"]' '~const'
 // @has - '//section[@id="impl-Tr%3CT%3E-for-T"]/h3[@class="code-header"]/div[@class="where"]' ': Fn'
-impl<T: /* ~const */ Fn() + ~const Destruct> const Tr<T> for T
+impl<T: /* ~const */ Fn() /* + ~const Destruct */> const Tr<T> for T
 where
-    Option<T>: /* ~const */ Fn() + ~const Destruct,
+    Option<T>: /* ~const */ Fn() /* + ~const Destruct */,
 {
-    fn a<A: /* ~const */ Fn() + ~const Destruct>()
+    fn a<A: /* ~const */ Fn() /* + ~const Destruct */>()
     where
-        Option<A>: /* ~const */ Fn() + ~const Destruct,
+        Option<A>: /* ~const */ Fn() /* + ~const Destruct */,
     {
     }
 }
@@ -51,9 +52,9 @@ fn a<A: /* ~const */ Fn() + ~const Destruct>()
 // @has - '//pre[@class="rust item-decl"]/code/a[@class="trait"]' 'Fn'
 // @!has - '//pre[@class="rust item-decl"]/code/div[@class="where"]' '~const'
 // @has - '//pre[@class="rust item-decl"]/code/div[@class="where"]' ': Fn'
-pub const fn foo<F: /* ~const */ Fn() + ~const Destruct>()
+pub const fn foo<F: /* ~const */ Fn() /* + ~const Destruct */>()
 where
-    Option<F>: /* ~const */ Fn() + ~const Destruct,
+    Option<F>: /* ~const */ Fn() /* + ~const Destruct */,
 {
     F::a()
 }
@@ -63,9 +64,9 @@ impl<T> S<T> {
     // @has - '//section[@id="method.foo"]/h4[@class="code-header"]/a[@class="trait"]' 'Fn'
     // @!has - '//section[@id="method.foo"]/h4[@class="code-header"]/span[@class="where"]' '~const'
     // @has - '//section[@id="method.foo"]/h4[@class="code-header"]/div[@class="where"]' ': Fn'
-    pub const fn foo<B, C: /* ~const */ Fn() + ~const Destruct>()
+    pub const fn foo<B, C: /* ~const */ Fn() /* + ~const Destruct */>()
     where
-        B: /* ~const */ Fn() + ~const Destruct,
+        B: /* ~const */ Fn() /* + ~const Destruct */,
     {
         B::a()
     }

tests/ui/const-generics/const_trait_fn-issue-88433.rs

@@ -1,6 +1,6 @@
 //@ build-pass
 
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 #[const_trait]
 trait Func<T> {

tests/ui/const-generics/const_trait_fn-issue-88433.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/const_trait_fn-issue-88433.rs:3:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/consts/auxiliary/closure-in-foreign-crate.rs

@@ -1,5 +1,5 @@
 #![crate_type = "lib"]
-#![feature(const_closures, const_trait_impl, effects)]
+#![feature(const_closures, const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 pub const fn test() {
     let cl = const || {};

tests/ui/consts/const-block-const-bound.stderr

@@ -1,3 +1,9 @@
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-block-const-bound.rs:8:22
+   |
+LL | const fn f<T: ~const Destruct>(x: T) {}
+   |                      ^^^^^^^^
+
 error[E0493]: destructor of `T` cannot be evaluated at compile-time
   --> $DIR/const-block-const-bound.rs:8:32
    |
@@ -6,6 +12,6 @@ LL | const fn f<T: ~const Destruct>(x: T) {}
    |                                |
    |                                the destructor for this type cannot be evaluated in constant functions
 
-error: aborting due to 1 previous error
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0493`.

tests/ui/consts/const-float-classify.rs

@@ -1,5 +1,6 @@
 //@ compile-flags: -Zmir-opt-level=0
-//@ run-pass
+//@ known-bug: #110395
+// FIXME(effects) run-pass
 
 #![feature(const_float_bits_conv)]
 #![feature(const_float_classify)]

tests/ui/consts/const-float-classify.stderr

@@ -0,0 +1,223 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/const-float-classify.rs:7:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+error: const `impl` for trait `PartialEq` which is not marked with `#[const_trait]`
+  --> $DIR/const-float-classify.rs:12:12
+   |
+LL | impl const PartialEq<NonDet> for bool {
+   |            ^^^^^^^^^^^^^^^^^
+   |
+   = note: marking a trait with `#[const_trait]` ensures all default method bodies are `const`
+   = note: adding a non-const method body in the future would be a breaking change
+
+error[E0207]: the const parameter `host` is not constrained by the impl trait, self type, or predicates
+  --> $DIR/const-float-classify.rs:12:6
+   |
+LL | impl const PartialEq<NonDet> for bool {
+   |      ^^^^^ unconstrained const parameter
+   |
+   = note: expressions using a const parameter must map each value to a distinct output value
+   = note: proving the result of expressions other than the parameter are unique is not supported
+
+error[E0284]: type annotations needed
+  --> $DIR/const-float-classify.rs:21:35
+   |
+LL |               const _: () = assert!($a == $b);
+   |                                     ^^ cannot infer the value of the constant `_`
+...
+LL | / suite! {
+LL | |                    [is_nan, is_infinite, is_finite, is_normal, is_sign_positive, is_sign_negative]
+LL | |      -0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+LL | |       0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+...  |
+LL | |      -1.0 / 0.0 => [ false,        true,     false,     false,            false,             true]
+LL | | }
+   | |_- in this macro invocation
+   |
+note: required for `bool` to implement `PartialEq<NonDet>`
+  --> $DIR/const-float-classify.rs:12:12
+   |
+LL | impl const PartialEq<NonDet> for bool {
+   |      ----- ^^^^^^^^^^^^^^^^^     ^^^^
+   |      |
+   |      unsatisfied trait bound introduced here
+   = note: this error originates in the macro `const_assert` which comes from the expansion of the macro `suite` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0284]: type annotations needed
+  --> $DIR/const-float-classify.rs:21:35
+   |
+LL |               const _: () = assert!($a == $b);
+   |                                     ^^ cannot infer the value of the constant `_`
+...
+LL | / suite! {
+LL | |                    [is_nan, is_infinite, is_finite, is_normal, is_sign_positive, is_sign_negative]
+LL | |      -0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+LL | |       0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+...  |
+LL | |      -1.0 / 0.0 => [ false,        true,     false,     false,            false,             true]
+LL | | }
+   | |_- in this macro invocation
+   |
+note: required for `bool` to implement `PartialEq<NonDet>`
+  --> $DIR/const-float-classify.rs:12:12
+   |
+LL | impl const PartialEq<NonDet> for bool {
+   |      ----- ^^^^^^^^^^^^^^^^^     ^^^^
+   |      |
+   |      unsatisfied trait bound introduced here
+   = note: this error originates in the macro `const_assert` which comes from the expansion of the macro `suite` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0284]: type annotations needed
+  --> $DIR/const-float-classify.rs:21:35
+   |
+LL |               const _: () = assert!($a == $b);
+   |                                     ^^ cannot infer the value of the constant `_`
+...
+LL | / suite! {
+LL | |                    [is_nan, is_infinite, is_finite, is_normal, is_sign_positive, is_sign_negative]
+LL | |      -0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+LL | |       0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+...  |
+LL | |      -1.0 / 0.0 => [ false,        true,     false,     false,            false,             true]
+LL | | }
+   | |_- in this macro invocation
+   |
+note: required for `bool` to implement `PartialEq<NonDet>`
+  --> $DIR/const-float-classify.rs:12:12
+   |
+LL | impl const PartialEq<NonDet> for bool {
+   |      ----- ^^^^^^^^^^^^^^^^^     ^^^^
+   |      |
+   |      unsatisfied trait bound introduced here
+   = note: this error originates in the macro `const_assert` which comes from the expansion of the macro `suite` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0284]: type annotations needed
+  --> $DIR/const-float-classify.rs:21:35
+   |
+LL |               const _: () = assert!($a == $b);
+   |                                     ^^ cannot infer the value of the constant `_`
+...
+LL | / suite! {
+LL | |                    [is_nan, is_infinite, is_finite, is_normal, is_sign_positive, is_sign_negative]
+LL | |      -0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+LL | |       0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+...  |
+LL | |      -1.0 / 0.0 => [ false,        true,     false,     false,            false,             true]
+LL | | }
+   | |_- in this macro invocation
+   |
+note: required for `bool` to implement `PartialEq<NonDet>`
+  --> $DIR/const-float-classify.rs:12:12
+   |
+LL | impl const PartialEq<NonDet> for bool {
+   |      ----- ^^^^^^^^^^^^^^^^^     ^^^^
+   |      |
+   |      unsatisfied trait bound introduced here
+   = note: this error originates in the macro `const_assert` which comes from the expansion of the macro `suite` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0284]: type annotations needed
+  --> $DIR/const-float-classify.rs:21:35
+   |
+LL |               const _: () = assert!($a == $b);
+   |                                     ^^ cannot infer the value of the constant `_`
+...
+LL | / suite! {
+LL | |                    [is_nan, is_infinite, is_finite, is_normal, is_sign_positive, is_sign_negative]
+LL | |      -0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+LL | |       0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+...  |
+LL | |      -1.0 / 0.0 => [ false,        true,     false,     false,            false,             true]
+LL | | }
+   | |_- in this macro invocation
+   |
+note: required for `bool` to implement `PartialEq<NonDet>`
+  --> $DIR/const-float-classify.rs:12:12
+   |
+LL | impl const PartialEq<NonDet> for bool {
+   |      ----- ^^^^^^^^^^^^^^^^^     ^^^^
+   |      |
+   |      unsatisfied trait bound introduced here
+   = note: this error originates in the macro `const_assert` which comes from the expansion of the macro `suite` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0284]: type annotations needed
+  --> $DIR/const-float-classify.rs:21:35
+   |
+LL |               const _: () = assert!($a == $b);
+   |                                     ^^ cannot infer the value of the constant `_`
+...
+LL | / suite! {
+LL | |                    [is_nan, is_infinite, is_finite, is_normal, is_sign_positive, is_sign_negative]
+LL | |      -0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+LL | |       0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+...  |
+LL | |      -1.0 / 0.0 => [ false,        true,     false,     false,            false,             true]
+LL | | }
+   | |_- in this macro invocation
+   |
+note: required for `bool` to implement `PartialEq<NonDet>`
+  --> $DIR/const-float-classify.rs:12:12
+   |
+LL | impl const PartialEq<NonDet> for bool {
+   |      ----- ^^^^^^^^^^^^^^^^^     ^^^^
+   |      |
+   |      unsatisfied trait bound introduced here
+   = note: this error originates in the macro `const_assert` which comes from the expansion of the macro `suite` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0284]: type annotations needed
+  --> $DIR/const-float-classify.rs:21:35
+   |
+LL |               const _: () = assert!($a == $b);
+   |                                     ^^ cannot infer the value of the constant `_`
+...
+LL | / suite! {
+LL | |                    [is_nan, is_infinite, is_finite, is_normal, is_sign_positive, is_sign_negative]
+LL | |      -0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+LL | |       0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+...  |
+LL | |      -1.0 / 0.0 => [ false,        true,     false,     false,            false,             true]
+LL | | }
+   | |_- in this macro invocation
+   |
+note: required for `bool` to implement `PartialEq<NonDet>`
+  --> $DIR/const-float-classify.rs:12:12
+   |
+LL | impl const PartialEq<NonDet> for bool {
+   |      ----- ^^^^^^^^^^^^^^^^^     ^^^^
+   |      |
+   |      unsatisfied trait bound introduced here
+   = note: this error originates in the macro `const_assert` which comes from the expansion of the macro `suite` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0284]: type annotations needed
+  --> $DIR/const-float-classify.rs:21:35
+   |
+LL |               const _: () = assert!($a == $b);
+   |                                     ^^ cannot infer the value of the constant `_`
+...
+LL | / suite! {
+LL | |                    [is_nan, is_infinite, is_finite, is_normal, is_sign_positive, is_sign_negative]
+LL | |      -0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+LL | |       0.0 / 0.0 => [  true,       false,     false,     false,           NonDet,           NonDet]
+...  |
+LL | |      -1.0 / 0.0 => [ false,        true,     false,     false,            false,             true]
+LL | | }
+   | |_- in this macro invocation
+   |
+note: required for `bool` to implement `PartialEq<NonDet>`
+  --> $DIR/const-float-classify.rs:12:12
+   |
+LL | impl const PartialEq<NonDet> for bool {
+   |      ----- ^^^^^^^^^^^^^^^^^     ^^^^
+   |      |
+   |      unsatisfied trait bound introduced here
+   = note: this error originates in the macro `const_assert` which comes from the expansion of the macro `suite` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to 10 previous errors; 1 warning emitted
+
+Some errors have detailed explanations: E0207, E0284.
+For more information about an error, try `rustc --explain E0207`.

tests/ui/consts/const_cmp_type_id.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/const_cmp_type_id.rs:3:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error[E0131]: `main` function is not allowed to have generic parameters
   --> $DIR/const_cmp_type_id.rs:7:14
    |
@@ -10,25 +19,7 @@ error[E0080]: evaluation of constant value failed
 LL |     const _A: bool = TypeId::of::<u8>() < TypeId::of::<u16>();
    |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ calling non-const function `<TypeId as PartialOrd>::lt`
 
-error[E0308]: mismatched types
-  --> $DIR/const_cmp_type_id.rs:8:13
-   |
-LL |     assert!(TypeId::of::<u8>() == TypeId::of::<u8>());
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `host`, found `true`
-   |
-   = note: expected constant `host`
-              found constant `true`
+error: aborting due to 2 previous errors; 1 warning emitted
 
-error[E0308]: mismatched types
-  --> $DIR/const_cmp_type_id.rs:9:13
-   |
-LL |     assert!(TypeId::of::<()>() != TypeId::of::<u8>());
-   |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `host`, found `true`
-   |
-   = note: expected constant `host`
-              found constant `true`
-
-error: aborting due to 4 previous errors
-
-Some errors have detailed explanations: E0080, E0131, E0308.
+Some errors have detailed explanations: E0080, E0131.
 For more information about an error, try `rustc --explain E0080`.

tests/ui/consts/fn_trait_refs.stderr

@@ -4,12 +4,24 @@ error[E0635]: unknown feature `const_fn_trait_ref_impls`
 LL | #![feature(const_fn_trait_ref_impls)]
    |            ^^^^^^^^^^^^^^^^^^^^^^^^
 
+error[E0635]: unknown feature `const_cmp`
+  --> $DIR/fn_trait_refs.rs:8:12
+   |
+LL | #![feature(const_cmp)]
+   |            ^^^^^^^^^
+
 error: `~const` can only be applied to `#[const_trait]` traits
   --> $DIR/fn_trait_refs.rs:15:15
    |
 LL |     T: ~const Fn<()> + ~const Destruct,
    |               ^^^^^^
 
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/fn_trait_refs.rs:15:31
+   |
+LL |     T: ~const Fn<()> + ~const Destruct,
+   |                               ^^^^^^^^
+
 error: `~const` can only be applied to `#[const_trait]` traits
   --> $DIR/fn_trait_refs.rs:15:15
    |
@@ -24,6 +36,12 @@ error: `~const` can only be applied to `#[const_trait]` traits
 LL |     T: ~const FnMut<()> + ~const Destruct,
    |               ^^^^^^^^^
 
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/fn_trait_refs.rs:22:34
+   |
+LL |     T: ~const FnMut<()> + ~const Destruct,
+   |                                  ^^^^^^^^
+
 error: `~const` can only be applied to `#[const_trait]` traits
   --> $DIR/fn_trait_refs.rs:22:15
    |
@@ -52,6 +70,12 @@ error: `~const` can only be applied to `#[const_trait]` traits
 LL |     T: ~const Fn<()> + ~const Destruct,
    |               ^^^^^^
 
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/fn_trait_refs.rs:36:31
+   |
+LL |     T: ~const Fn<()> + ~const Destruct,
+   |                               ^^^^^^^^
+
 error: `~const` can only be applied to `#[const_trait]` traits
   --> $DIR/fn_trait_refs.rs:36:15
    |
@@ -66,6 +90,12 @@ error: `~const` can only be applied to `#[const_trait]` traits
 LL |     T: ~const FnMut<()> + ~const Destruct,
    |               ^^^^^^^^^
 
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/fn_trait_refs.rs:50:34
+   |
+LL |     T: ~const FnMut<()> + ~const Destruct,
+   |                                  ^^^^^^^^
+
 error: `~const` can only be applied to `#[const_trait]` traits
   --> $DIR/fn_trait_refs.rs:50:15
    |
@@ -182,7 +212,7 @@ LL | const fn test_fn_mut<T>(mut f: T) -> (T::Output, T::Output)
 LL | }
    | - value is dropped here
 
-error: aborting due to 20 previous errors
+error: aborting due to 25 previous errors
 
 Some errors have detailed explanations: E0015, E0493, E0635.
 For more information about an error, try `rustc --explain E0015`.

tests/ui/consts/rustc-impl-const-stability.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/rustc-impl-const-stability.rs:5:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error: const `impl` for trait `Default` which is not marked with `#[const_trait]`
   --> $DIR/rustc-impl-const-stability.rs:15:12
    |
@@ -16,6 +25,6 @@ LL | impl const Default for Data {
    = note: expressions using a const parameter must map each value to a distinct output value
    = note: proving the result of expressions other than the parameter are unique is not supported
 
-error: aborting due to 2 previous errors
+error: aborting due to 2 previous errors; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0207`.

tests/ui/impl-trait/normalize-tait-in-const.stderr

@@ -4,6 +4,12 @@ error: `~const` can only be applied to `#[const_trait]` traits
 LL | const fn with_positive<F: ~const for<'a> Fn(&'a Alias<'a>) + ~const Destruct>(fun: F) {
    |                                          ^^^^^^^^^^^^^^^^^
 
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/normalize-tait-in-const.rs:27:69
+   |
+LL | const fn with_positive<F: ~const for<'a> Fn(&'a Alias<'a>) + ~const Destruct>(fun: F) {
+   |                                                                     ^^^^^^^^
+
 error[E0015]: cannot call non-const closure in constant functions
   --> $DIR/normalize-tait-in-const.rs:28:5
    |
@@ -29,7 +35,7 @@ LL |     fun(filter_positive());
 LL | }
    | - value is dropped here
 
-error: aborting due to 3 previous errors
+error: aborting due to 4 previous errors
 
 Some errors have detailed explanations: E0015, E0493.
 For more information about an error, try `rustc --explain E0015`.

tests/ui/intrinsics/not-overridden.rs

@@ -1,6 +1,6 @@
 //! Check that intrinsics that do not get overridden, but are marked as such,
 //! cause an error instead of silently invoking the body.
-#![feature(rustc_attrs, effects)]
+#![feature(rustc_attrs/* , effects*/)] // FIXME(effects)
 //@ build-fail
 //@ failure-status:101
 //@ normalize-stderr-test ".*note: .*\n\n" -> ""

tests/ui/intrinsics/safe-intrinsic-mismatch.rs

@@ -1,6 +1,6 @@
 #![feature(intrinsics)]
 #![feature(rustc_attrs)]
-#![feature(effects)]
+// FIXME(effects) do this with revisions #![feature(effects)]
 
 extern "rust-intrinsic" {
     fn size_of<T>() -> usize; //~ ERROR intrinsic safety mismatch
@@ -19,7 +19,7 @@ const fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
 mod foo {
     #[rustc_intrinsic]
     unsafe fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
-    //~^ ERROR wrong number of const parameters
+    // FIXME(effects) ~^ ERROR wrong number of const parameters
 }
 
 fn main() {}

tests/ui/intrinsics/safe-intrinsic-mismatch.stderr

@@ -42,13 +42,6 @@ LL | const fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
    = note: expected signature `unsafe fn(_, _, _)`
               found signature `fn(_, _, _)`
 
-error[E0094]: intrinsic has wrong number of const parameters: found 0, expected 1
-  --> $DIR/safe-intrinsic-mismatch.rs:21:31
-   |
-LL |     unsafe fn const_deallocate(_ptr: *mut u8, _size: usize, _align: usize) {}
-   |                               ^ expected 1 const parameter
+error: aborting due to 6 previous errors
 
-error: aborting due to 7 previous errors
-
-Some errors have detailed explanations: E0094, E0308.
-For more information about an error, try `rustc --explain E0094`.
+For more information about this error, try `rustc --explain E0308`.

tests/ui/parser/impls-nested-within-fns-semantic-1.rs

@@ -1,7 +1,7 @@
 // Regression test for part of issue #119924.
 //@ check-pass
 
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 #[const_trait]
 trait Trait {

tests/ui/parser/impls-nested-within-fns-semantic-1.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/impls-nested-within-fns-semantic-1.rs:4:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/rfcs/rfc-2632-const-trait-impl/assoc-type-const-bound-usage-0.qualified.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/assoc-type-const-bound-usage-0.rs:6:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error[E0277]: the trait bound `T: Trait` is not satisfied
   --> $DIR/assoc-type-const-bound-usage-0.rs:21:6
    |
@@ -9,6 +18,6 @@ help: consider further restricting this bound
 LL | const fn qualified<T: ~const Trait + Trait>() -> i32 {
    |                                    +++++++
 
-error: aborting due to 1 previous error
+error: aborting due to 1 previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0277`.

tests/ui/rfcs/rfc-2632-const-trait-impl/assoc-type-const-bound-usage-0.rs

@@ -3,7 +3,7 @@
 //@[unqualified] check-pass
 //@[qualified] known-bug: unknown
 
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //[unqualified]~ WARN the feature `effects` is incomplete
 
 #[const_trait]
 trait Trait {

tests/ui/rfcs/rfc-2632-const-trait-impl/assoc-type-const-bound-usage-0.unqualified.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/assoc-type-const-bound-usage-0.rs:6:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/rfcs/rfc-2632-const-trait-impl/assoc-type.rs

@@ -1,5 +1,5 @@
 // FIXME(effects): Replace `Add` with `std::ops::Add` once the latter a `#[const_trait]` again.
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 #[const_trait]
 trait Add<Rhs = Self> {

tests/ui/rfcs/rfc-2632-const-trait-impl/assoc-type.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/assoc-type.rs:2:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error[E0277]: the trait bound `NonConstAdd: ~const Add` is not satisfied
   --> $DIR/assoc-type.rs:35:16
    |
@@ -11,6 +20,6 @@ note: required by a bound in `Foo::Bar`
 LL |     type Bar: ~const Add;
    |               ^^^^^^^^^^ required by this bound in `Foo::Bar`
 
-error: aborting due to 1 previous error
+error: aborting due to 1 previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0277`.

tests/ui/rfcs/rfc-2632-const-trait-impl/auxiliary/cross-crate.rs

@@ -1,4 +1,4 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 #[const_trait]
 pub trait MyTrait {

tests/ui/rfcs/rfc-2632-const-trait-impl/auxiliary/staged-api.rs

@@ -1,4 +1,4 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 #![feature(staged_api)]
 #![stable(feature = "rust1", since = "1.0.0")]
 

tests/ui/rfcs/rfc-2632-const-trait-impl/call-const-trait-method-fail.rs

@@ -1,4 +1,4 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 #[const_trait]
 pub trait Plus {

tests/ui/rfcs/rfc-2632-const-trait-impl/call-const-trait-method-fail.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/call-const-trait-method-fail.rs:1:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error[E0277]: the trait bound `u32: ~const Plus` is not satisfied
   --> $DIR/call-const-trait-method-fail.rs:25:5
    |
@@ -6,6 +15,6 @@ LL |     a.plus(b)
    |
    = help: the trait `Plus` is implemented for `u32`
 
-error: aborting due to 1 previous error
+error: aborting due to 1 previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0277`.

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-in-impl.rs

@@ -1,4 +1,5 @@
-//@ check-pass
+//@ known-bug: #110395
+// FIXME(effects) check-pass
 #![feature(const_trait_impl)]
 
 #[const_trait]

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-in-impl.stderr

@@ -0,0 +1,8 @@
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/call-generic-in-impl.rs:10:16
+   |
+LL | impl<T: ~const PartialEq> const MyPartialEq for T {
+   |                ^^^^^^^^^
+
+error: aborting due to 1 previous error
+

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-chain.rs

@@ -1,6 +1,7 @@
 //! Basic test for calling methods on generic type parameters in `const fn`.
 
-//@ check-pass
+//@ known-bug: #110395
+// FIXME(effects) check-pass
 
 #![feature(const_trait_impl, effects)]
 

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-chain.stderr

@@ -0,0 +1,71 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/call-generic-method-chain.rs:6:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+error: const `impl` for trait `PartialEq` which is not marked with `#[const_trait]`
+  --> $DIR/call-generic-method-chain.rs:10:12
+   |
+LL | impl const PartialEq for S {
+   |            ^^^^^^^^^
+   |
+   = note: marking a trait with `#[const_trait]` ensures all default method bodies are `const`
+   = note: adding a non-const method body in the future would be a breaking change
+
+error[E0207]: the const parameter `host` is not constrained by the impl trait, self type, or predicates
+  --> $DIR/call-generic-method-chain.rs:10:6
+   |
+LL | impl const PartialEq for S {
+   |      ^^^^^ unconstrained const parameter
+   |
+   = note: expressions using a const parameter must map each value to a distinct output value
+   = note: proving the result of expressions other than the parameter are unique is not supported
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/call-generic-method-chain.rs:19:32
+   |
+LL | const fn equals_self<T: ~const PartialEq>(t: &T) -> bool {
+   |                                ^^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/call-generic-method-chain.rs:23:40
+   |
+LL | const fn equals_self_wrapper<T: ~const PartialEq>(t: &T) -> bool {
+   |                                        ^^^^^^^^^
+
+error[E0284]: type annotations needed
+  --> $DIR/call-generic-method-chain.rs:27:22
+   |
+LL | pub const EQ: bool = equals_self_wrapper(&S);
+   |                      ^^^^^^^^^^^^^^^^^^^^^^^ cannot infer the value of the constant `_`
+   |
+note: required for `S` to implement `PartialEq`
+  --> $DIR/call-generic-method-chain.rs:10:12
+   |
+LL | impl const PartialEq for S {
+   |      ----- ^^^^^^^^^     ^
+   |      |
+   |      unsatisfied trait bound introduced here
+
+error[E0284]: type annotations needed
+  --> $DIR/call-generic-method-chain.rs:15:10
+   |
+LL |         !self.eq(other)
+   |          ^^^^^^^^^^^^^^ cannot infer the value of the constant `_`
+   |
+note: required for `S` to implement `PartialEq`
+  --> $DIR/call-generic-method-chain.rs:10:12
+   |
+LL | impl const PartialEq for S {
+   |      ----- ^^^^^^^^^     ^
+   |      |
+   |      unsatisfied trait bound introduced here
+
+error: aborting due to 6 previous errors; 1 warning emitted
+
+Some errors have detailed explanations: E0207, E0284.
+For more information about an error, try `rustc --explain E0207`.

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-dup-bound.rs

@@ -1,4 +1,5 @@
-//@ check-pass
+//@ known-bug: #110395
+// FIXME(effects) check-pass
 
 #![feature(const_trait_impl, effects)]
 

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-dup-bound.stderr

@@ -0,0 +1,85 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/call-generic-method-dup-bound.rs:4:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+error: const `impl` for trait `PartialEq` which is not marked with `#[const_trait]`
+  --> $DIR/call-generic-method-dup-bound.rs:8:12
+   |
+LL | impl const PartialEq for S {
+   |            ^^^^^^^^^
+   |
+   = note: marking a trait with `#[const_trait]` ensures all default method bodies are `const`
+   = note: adding a non-const method body in the future would be a breaking change
+
+error[E0207]: the const parameter `host` is not constrained by the impl trait, self type, or predicates
+  --> $DIR/call-generic-method-dup-bound.rs:8:6
+   |
+LL | impl const PartialEq for S {
+   |      ^^^^^ unconstrained const parameter
+   |
+   = note: expressions using a const parameter must map each value to a distinct output value
+   = note: proving the result of expressions other than the parameter are unique is not supported
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/call-generic-method-dup-bound.rs:19:44
+   |
+LL | const fn equals_self<T: PartialEq + ~const PartialEq>(t: &T) -> bool {
+   |                                            ^^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/call-generic-method-dup-bound.rs:26:37
+   |
+LL | const fn equals_self2<T: A + ~const PartialEq>(t: &T) -> bool {
+   |                                     ^^^^^^^^^
+
+error[E0284]: type annotations needed
+  --> $DIR/call-generic-method-dup-bound.rs:30:22
+   |
+LL | pub const EQ: bool = equals_self(&S) && equals_self2(&S);
+   |                      ^^^^^^^^^^^^^^^ cannot infer the value of the constant `_`
+   |
+note: required for `S` to implement `PartialEq`
+  --> $DIR/call-generic-method-dup-bound.rs:8:12
+   |
+LL | impl const PartialEq for S {
+   |      ----- ^^^^^^^^^     ^
+   |      |
+   |      unsatisfied trait bound introduced here
+
+error[E0284]: type annotations needed
+  --> $DIR/call-generic-method-dup-bound.rs:30:41
+   |
+LL | pub const EQ: bool = equals_self(&S) && equals_self2(&S);
+   |                                         ^^^^^^^^^^^^^^^^ cannot infer the value of the constant `_`
+   |
+note: required for `S` to implement `PartialEq`
+  --> $DIR/call-generic-method-dup-bound.rs:8:12
+   |
+LL | impl const PartialEq for S {
+   |      ----- ^^^^^^^^^     ^
+   |      |
+   |      unsatisfied trait bound introduced here
+
+error[E0284]: type annotations needed
+  --> $DIR/call-generic-method-dup-bound.rs:13:10
+   |
+LL |         !self.eq(other)
+   |          ^^^^^^^^^^^^^^ cannot infer the value of the constant `_`
+   |
+note: required for `S` to implement `PartialEq`
+  --> $DIR/call-generic-method-dup-bound.rs:8:12
+   |
+LL | impl const PartialEq for S {
+   |      ----- ^^^^^^^^^     ^
+   |      |
+   |      unsatisfied trait bound introduced here
+
+error: aborting due to 7 previous errors; 1 warning emitted
+
+Some errors have detailed explanations: E0207, E0284.
+For more information about an error, try `rustc --explain E0207`.

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-fail.rs

@@ -1,8 +1,10 @@
-#![feature(const_trait_impl, effects)]
+//@ check-pass
+
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 pub const fn equals_self<T: PartialEq>(t: &T) -> bool {
     *t == *t
-    //~^ ERROR mismatched types
+    // FIXME(effects) ~^ ERROR mismatched types
     // FIXME(effects): diagnostic
 }
 

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-fail.stderr

@@ -1,12 +1,11 @@
-error[E0308]: mismatched types
-  --> $DIR/call-generic-method-fail.rs:4:5
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/call-generic-method-fail.rs:3:30
    |
-LL |     *t == *t
-   |     ^^^^^^^^ expected `host`, found `true`
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
    |
-   = note: expected constant `host`
-              found constant `true`
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
 
-error: aborting due to 1 previous error
+warning: 1 warning emitted
 
-For more information about this error, try `rustc --explain E0308`.

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-nonconst.rs

@@ -1,4 +1,4 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 struct S;
 

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-nonconst.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/call-generic-method-nonconst.rs:1:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error[E0277]: the trait bound `S: const Foo` is not satisfied
   --> $DIR/call-generic-method-nonconst.rs:23:34
    |
@@ -13,6 +22,6 @@ note: required by a bound in `equals_self`
 LL | const fn equals_self<T: ~const Foo>(t: &T) -> bool {
    |                         ^^^^^^^^^^ required by this bound in `equals_self`
 
-error: aborting due to 1 previous error
+error: aborting due to 1 previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0277`.

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-pass.rs

@@ -1,6 +1,7 @@
 //! Basic test for calling methods on generic type parameters in `const fn`.
 
-//@ check-pass
+//@ known-bug: #110395
+// FIXME(effects) check-pass
 
 #![feature(const_trait_impl, effects)]
 

tests/ui/rfcs/rfc-2632-const-trait-impl/call-generic-method-pass.stderr

@@ -0,0 +1,65 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/call-generic-method-pass.rs:6:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+error: const `impl` for trait `PartialEq` which is not marked with `#[const_trait]`
+  --> $DIR/call-generic-method-pass.rs:10:12
+   |
+LL | impl const PartialEq for S {
+   |            ^^^^^^^^^
+   |
+   = note: marking a trait with `#[const_trait]` ensures all default method bodies are `const`
+   = note: adding a non-const method body in the future would be a breaking change
+
+error[E0207]: the const parameter `host` is not constrained by the impl trait, self type, or predicates
+  --> $DIR/call-generic-method-pass.rs:10:6
+   |
+LL | impl const PartialEq for S {
+   |      ^^^^^ unconstrained const parameter
+   |
+   = note: expressions using a const parameter must map each value to a distinct output value
+   = note: proving the result of expressions other than the parameter are unique is not supported
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/call-generic-method-pass.rs:19:32
+   |
+LL | const fn equals_self<T: ~const PartialEq>(t: &T) -> bool {
+   |                                ^^^^^^^^^
+
+error[E0284]: type annotations needed
+  --> $DIR/call-generic-method-pass.rs:23:22
+   |
+LL | pub const EQ: bool = equals_self(&S);
+   |                      ^^^^^^^^^^^^^^^ cannot infer the value of the constant `_`
+   |
+note: required for `S` to implement `PartialEq`
+  --> $DIR/call-generic-method-pass.rs:10:12
+   |
+LL | impl const PartialEq for S {
+   |      ----- ^^^^^^^^^     ^
+   |      |
+   |      unsatisfied trait bound introduced here
+
+error[E0284]: type annotations needed
+  --> $DIR/call-generic-method-pass.rs:15:10
+   |
+LL |         !self.eq(other)
+   |          ^^^^^^^^^^^^^^ cannot infer the value of the constant `_`
+   |
+note: required for `S` to implement `PartialEq`
+  --> $DIR/call-generic-method-pass.rs:10:12
+   |
+LL | impl const PartialEq for S {
+   |      ----- ^^^^^^^^^     ^
+   |      |
+   |      unsatisfied trait bound introduced here
+
+error: aborting due to 5 previous errors; 1 warning emitted
+
+Some errors have detailed explanations: E0207, E0284.
+For more information about an error, try `rustc --explain E0207`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-and-non-const-impl.stderr

@@ -1,3 +1,12 @@
+error[E0119]: conflicting implementations of trait `Add` for type `Int`
+  --> $DIR/const-and-non-const-impl.rs:23:1
+   |
+LL | impl std::ops::Add for Int {
+   | -------------------------- first implementation here
+...
+LL | impl const std::ops::Add for Int {
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `Int`
+
 error[E0117]: only traits defined in the current crate can be implemented for primitive types
   --> $DIR/const-and-non-const-impl.rs:7:1
    |
@@ -10,15 +19,6 @@ LL | impl const std::ops::Add for i32 {
    |
    = note: define and implement a trait or new type instead
 
-error[E0119]: conflicting implementations of trait `Add` for type `Int`
-  --> $DIR/const-and-non-const-impl.rs:23:1
-   |
-LL | impl std::ops::Add for Int {
-   | -------------------------- first implementation here
-...
-LL | impl const std::ops::Add for Int {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `Int`
-
 error: aborting due to 2 previous errors
 
 Some errors have detailed explanations: E0117, E0119.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-bounds-non-const-trait.rs

@@ -1,5 +1,5 @@
 // Regression test for issue #117244.
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 trait NonConst {}
 

tests/ui/rfcs/rfc-2632-const-trait-impl/const-bounds-non-const-trait.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/const-bounds-non-const-trait.rs:2:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error: `~const` can only be applied to `#[const_trait]` traits
   --> $DIR/const-bounds-non-const-trait.rs:6:28
    |
@@ -10,5 +19,5 @@ error: `const` can only be applied to `#[const_trait]` traits
 LL | fn operate<T: const NonConst>() {}
    |                     ^^^^^^^^
 
-error: aborting due to 2 previous errors
+error: aborting due to 2 previous errors; 1 warning emitted
 

tests/ui/rfcs/rfc-2632-const-trait-impl/const-check-fns-in-const-impl.rs

@@ -1,4 +1,4 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 struct S;
 #[const_trait]

tests/ui/rfcs/rfc-2632-const-trait-impl/const-check-fns-in-const-impl.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/const-check-fns-in-const-impl.rs:1:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error[E0015]: cannot call non-const fn `non_const` in constant functions
   --> $DIR/const-check-fns-in-const-impl.rs:12:16
    |
@@ -6,6 +15,6 @@ LL |     fn foo() { non_const() }
    |
    = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants
 
-error: aborting due to 1 previous error
+error: aborting due to 1 previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0015`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-default-method-bodies.rs

@@ -1,4 +1,4 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 #[const_trait]
 trait ConstDefaultFn: Sized {

tests/ui/rfcs/rfc-2632-const-trait-impl/const-default-method-bodies.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/const-default-method-bodies.rs:1:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error[E0277]: the trait bound `NonConstImpl: ~const ConstDefaultFn` is not satisfied
   --> $DIR/const-default-method-bodies.rs:24:18
    |
@@ -6,6 +15,6 @@ LL |     NonConstImpl.a();
    |
    = help: the trait `ConstDefaultFn` is implemented for `NonConstImpl`
 
-error: aborting due to 1 previous error
+error: aborting due to 1 previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0277`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-drop-bound.stderr

@@ -1,9 +1,27 @@
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-drop-bound.rs:9:68
+   |
+LL | const fn foo<T, E>(res: Result<T, E>) -> Option<T> where E: ~const Destruct {
+   |                                                                    ^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-drop-bound.rs:20:15
+   |
+LL |     T: ~const Destruct,
+   |               ^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-drop-bound.rs:21:15
+   |
+LL |     E: ~const Destruct,
+   |               ^^^^^^^^
+
 error[E0493]: destructor of `E` cannot be evaluated at compile-time
   --> $DIR/const-drop-bound.rs:12:13
    |
 LL |         Err(_e) => None,
    |             ^^ the destructor for this type cannot be evaluated in constant functions
 
-error: aborting due to 1 previous error
+error: aborting due to 4 previous errors
 
 For more information about this error, try `rustc --explain E0493`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-drop-fail-2.stderr

@@ -1,3 +1,9 @@
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-drop-fail-2.rs:21:26
+   |
+LL | const fn check<T: ~const Destruct>(_: T) {}
+   |                          ^^^^^^^^
+
 error[E0493]: destructor of `T` cannot be evaluated at compile-time
   --> $DIR/const-drop-fail-2.rs:21:36
    |
@@ -6,6 +12,6 @@ LL | const fn check<T: ~const Destruct>(_: T) {}
    |                                    |
    |                                    the destructor for this type cannot be evaluated in constant functions
 
-error: aborting due to 1 previous error
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0493`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-drop-fail.precise.stderr

@@ -1,3 +1,9 @@
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-drop-fail.rs:24:26
+   |
+LL | const fn check<T: ~const Destruct>(_: T) {}
+   |                          ^^^^^^^^
+
 error[E0493]: destructor of `T` cannot be evaluated at compile-time
   --> $DIR/const-drop-fail.rs:24:36
    |
@@ -54,7 +60,7 @@ LL | | }
    | |_- in this macro invocation
    = note: this error originates in the macro `check_all` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to 3 previous errors
+error: aborting due to 4 previous errors
 
 Some errors have detailed explanations: E0080, E0493.
 For more information about an error, try `rustc --explain E0080`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-drop-fail.stock.stderr

@@ -1,3 +1,9 @@
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-drop-fail.rs:24:26
+   |
+LL | const fn check<T: ~const Destruct>(_: T) {}
+   |                          ^^^^^^^^
+
 error[E0493]: destructor of `T` cannot be evaluated at compile-time
   --> $DIR/const-drop-fail.rs:24:36
    |
@@ -6,6 +12,6 @@ LL | const fn check<T: ~const Destruct>(_: T) {}
    |                                    |
    |                                    the destructor for this type cannot be evaluated in constant functions
 
-error: aborting due to 1 previous error
+error: aborting due to 2 previous errors
 
 For more information about this error, try `rustc --explain E0493`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-drop.precise.stderr

@@ -1,3 +1,9 @@
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-drop.rs:19:22
+   |
+LL | const fn a<T: ~const Destruct>(_: T) {}
+   |                      ^^^^^^^^
+
 error[E0493]: destructor of `S<'_>` cannot be evaluated at compile-time
   --> $DIR/const-drop.rs:24:13
    |
@@ -86,7 +92,7 @@ LL | | }
    | |_- in this macro invocation
    = note: this error originates in the macro `implements_const_drop` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to 5 previous errors
+error: aborting due to 6 previous errors
 
 Some errors have detailed explanations: E0080, E0493.
 For more information about an error, try `rustc --explain E0080`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-drop.stock.stderr

@@ -1,3 +1,9 @@
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-drop.rs:19:22
+   |
+LL | const fn a<T: ~const Destruct>(_: T) {}
+   |                      ^^^^^^^^
+
 error[E0493]: destructor of `S<'_>` cannot be evaluated at compile-time
   --> $DIR/const-drop.rs:24:13
    |
@@ -14,6 +20,6 @@ LL | const fn a<T: ~const Destruct>(_: T) {}
    |                                |
    |                                the destructor for this type cannot be evaluated in constant functions
 
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 
 For more information about this error, try `rustc --explain E0493`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-fns-are-early-bound.rs

@@ -7,7 +7,7 @@
 #![feature(
     auto_traits,
     const_trait_impl,
-    effects,
+    effects,  //~ WARN the feature `effects` is incomplete
     lang_items,
     no_core,
     staged_api,

tests/ui/rfcs/rfc-2632-const-trait-impl/const-fns-are-early-bound.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/const-fns-are-early-bound.rs:10:5
+   |
+LL |     effects,
+   |     ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/rfcs/rfc-2632-const-trait-impl/const-impl-requires-const-trait.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/const-impl-requires-const-trait.rs:3:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error: const `impl` for trait `A` which is not marked with `#[const_trait]`
   --> $DIR/const-impl-requires-const-trait.rs:8:12
    |
@@ -19,6 +28,6 @@ LL | impl const A for () {}
    = note: expressions using a const parameter must map each value to a distinct output value
    = note: proving the result of expressions other than the parameter are unique is not supported
 
-error: aborting due to 2 previous errors
+error: aborting due to 2 previous errors; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0207`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-impl-trait.stderr

@@ -1,28 +1,244 @@
-error[E0277]: can't compare `()` with `()`
-  --> $DIR/const-impl-trait.rs:36:17
+error[E0635]: unknown feature `const_cmp`
+  --> $DIR/const-impl-trait.rs:8:5
    |
-LL |     assert!(cmp(&()));
-   |             --- ^^^ no implementation for `() == ()`
-   |             |
-   |             required by a bound introduced by this call
-   |
-   = help: the trait `const PartialEq` is not implemented for `()`
-   = help: the trait `PartialEq` is implemented for `()`
-note: required by a bound in `cmp`
-  --> $DIR/const-impl-trait.rs:13:23
+LL |     const_cmp,
+   |     ^^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:13:30
    |
 LL | const fn cmp(a: &impl ~const PartialEq) -> bool {
-   |                       ^^^^^^^^^^^^^^^^ required by this bound in `cmp`
+   |                              ^^^^^^^^^
 
-error[E0369]: binary operation `==` cannot be applied to type `&impl ~const PartialEq`
-  --> $DIR/const-impl-trait.rs:14:7
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:17:30
    |
-LL |     a == a
-   |     - ^^ - &impl ~const PartialEq
-   |     |
-   |     &impl ~const PartialEq
+LL | const fn wrap(x: impl ~const PartialEq + ~const Destruct)
+   |                              ^^^^^^^^^
 
-error: aborting due to 2 previous errors
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:17:49
+   |
+LL | const fn wrap(x: impl ~const PartialEq + ~const Destruct)
+   |                                                 ^^^^^^^^
 
-Some errors have detailed explanations: E0277, E0369.
-For more information about an error, try `rustc --explain E0277`.
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:18:20
+   |
+LL |     -> impl ~const PartialEq + ~const Destruct
+   |                    ^^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:18:39
+   |
+LL |     -> impl ~const PartialEq + ~const Destruct
+   |                                       ^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:18:20
+   |
+LL |     -> impl ~const PartialEq + ~const Destruct
+   |                    ^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:18:39
+   |
+LL |     -> impl ~const PartialEq + ~const Destruct
+   |                                       ^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:25:29
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                             ^^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:25:48
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                                                ^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:25:29
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                             ^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:25:48
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                                                ^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:25:29
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                             ^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:25:48
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                                                ^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:29:29
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy {
+   |                             ^^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:29:48
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy {
+   |                                                ^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:29:29
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy {
+   |                             ^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:29:48
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy {
+   |                                                ^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:50:41
+   |
+LL | const fn apit(_: impl ~const T + ~const Destruct) {}
+   |                                         ^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:54:73
+   |
+LL | const fn apit_assoc_bound(_: impl IntoIterator<Item: ~const T> + ~const Destruct) {}
+   |                                                                         ^^^^^^^^
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:25:29
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                             ^^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/const-impl-trait.rs:25:48
+   |
+LL |     fn huh() -> impl ~const PartialEq + ~const Destruct + Copy;
+   |                                                ^^^^^^^^
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error[E0493]: destructor of `impl PartialEq + Destruct` cannot be evaluated at compile-time
+  --> $DIR/const-impl-trait.rs:37:26
+   |
+LL |     assert!(wrap(123) == wrap(123));
+   |                          ^^^^^^^^^- value is dropped here
+   |                          |
+   |                          the destructor for this type cannot be evaluated in constants
+
+error[E0493]: destructor of `impl PartialEq + Destruct` cannot be evaluated at compile-time
+  --> $DIR/const-impl-trait.rs:37:26
+   |
+LL |     assert!(wrap(123) == wrap(123));
+   |                          ^^^^^^^^^- value is dropped here
+   |                          |
+   |                          the destructor for this type cannot be evaluated in constants
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error[E0493]: destructor of `impl PartialEq + Destruct` cannot be evaluated at compile-time
+  --> $DIR/const-impl-trait.rs:37:13
+   |
+LL |     assert!(wrap(123) == wrap(123));
+   |             ^^^^^^^^^             - value is dropped here
+   |             |
+   |             the destructor for this type cannot be evaluated in constants
+
+error[E0493]: destructor of `impl PartialEq + Destruct` cannot be evaluated at compile-time
+  --> $DIR/const-impl-trait.rs:37:13
+   |
+LL |     assert!(wrap(123) == wrap(123));
+   |             ^^^^^^^^^             - value is dropped here
+   |             |
+   |             the destructor for this type cannot be evaluated in constants
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error[E0493]: destructor of `impl PartialEq + Destruct` cannot be evaluated at compile-time
+  --> $DIR/const-impl-trait.rs:38:26
+   |
+LL |     assert!(wrap(123) != wrap(456));
+   |                          ^^^^^^^^^- value is dropped here
+   |                          |
+   |                          the destructor for this type cannot be evaluated in constants
+
+error[E0493]: destructor of `impl PartialEq + Destruct` cannot be evaluated at compile-time
+  --> $DIR/const-impl-trait.rs:38:26
+   |
+LL |     assert!(wrap(123) != wrap(456));
+   |                          ^^^^^^^^^- value is dropped here
+   |                          |
+   |                          the destructor for this type cannot be evaluated in constants
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error[E0493]: destructor of `impl PartialEq + Destruct` cannot be evaluated at compile-time
+  --> $DIR/const-impl-trait.rs:38:13
+   |
+LL |     assert!(wrap(123) != wrap(456));
+   |             ^^^^^^^^^             - value is dropped here
+   |             |
+   |             the destructor for this type cannot be evaluated in constants
+
+error[E0493]: destructor of `impl PartialEq + Destruct` cannot be evaluated at compile-time
+  --> $DIR/const-impl-trait.rs:38:13
+   |
+LL |     assert!(wrap(123) != wrap(456));
+   |             ^^^^^^^^^             - value is dropped here
+   |             |
+   |             the destructor for this type cannot be evaluated in constants
+   |
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
+error[E0493]: destructor of `impl ~const T + ~const Destruct` cannot be evaluated at compile-time
+  --> $DIR/const-impl-trait.rs:50:15
+   |
+LL | const fn apit(_: impl ~const T + ~const Destruct) {}
+   |               ^                                    - value is dropped here
+   |               |
+   |               the destructor for this type cannot be evaluated in constant functions
+
+error[E0493]: destructor of `impl IntoIterator<Item : ~const T> + ~const Destruct` cannot be evaluated at compile-time
+  --> $DIR/const-impl-trait.rs:54:27
+   |
+LL | const fn apit_assoc_bound(_: impl IntoIterator<Item: ~const T> + ~const Destruct) {}
+   |                           ^                                                        - value is dropped here
+   |                           |
+   |                           the destructor for this type cannot be evaluated in constant functions
+
+error: aborting due to 32 previous errors
+
+Some errors have detailed explanations: E0493, E0635.
+For more information about an error, try `rustc --explain E0493`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const-trait-bounds-trait-objects.rs

@@ -1,4 +1,4 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 //@ edition: 2021
 
 #[const_trait]

tests/ui/rfcs/rfc-2632-const-trait-impl/const-trait-bounds-trait-objects.stderr

@@ -26,5 +26,14 @@ LL | const fn take(_: &dyn ~const NonConst) {}
    |
    = note: trait objects cannot have `~const` trait bounds
 
-error: aborting due to 4 previous errors
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/const-trait-bounds-trait-objects.rs:1:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+error: aborting due to 4 previous errors; 1 warning emitted
 

tests/ui/rfcs/rfc-2632-const-trait-impl/const_derives/derive-const-non-const-type.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/derive-const-non-const-type.rs:2:26
+   |
+LL | #![feature(derive_const, effects)]
+   |                          ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error: const `impl` for trait `Default` which is not marked with `#[const_trait]`
   --> $DIR/derive-const-non-const-type.rs:10:16
    |
@@ -13,6 +22,6 @@ error[E0207]: the const parameter `host` is not constrained by the impl trait, s
    = note: expressions using a const parameter must map each value to a distinct output value
    = note: proving the result of expressions other than the parameter are unique is not supported
 
-error: aborting due to 2 previous errors
+error: aborting due to 2 previous errors; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0207`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const_derives/derive-const-use.stderr

@@ -1,3 +1,18 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/derive-const-use.rs:3:76
+   |
+LL | #![feature(const_trait_impl, const_cmp, const_default_impls, derive_const, effects)]
+   |                                                                            ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+error[E0635]: unknown feature `const_cmp`
+  --> $DIR/derive-const-use.rs:3:30
+   |
+LL | #![feature(const_trait_impl, const_cmp, const_default_impls, derive_const, effects)]
+   |                              ^^^^^^^^^
+
 error[E0635]: unknown feature `const_default_impls`
   --> $DIR/derive-const-use.rs:3:41
    |
@@ -22,6 +37,24 @@ LL | impl const Default for A {
    = note: expressions using a const parameter must map each value to a distinct output value
    = note: proving the result of expressions other than the parameter are unique is not supported
 
+error: const `impl` for trait `PartialEq` which is not marked with `#[const_trait]`
+  --> $DIR/derive-const-use.rs:11:12
+   |
+LL | impl const PartialEq for A {
+   |            ^^^^^^^^^
+   |
+   = note: marking a trait with `#[const_trait]` ensures all default method bodies are `const`
+   = note: adding a non-const method body in the future would be a breaking change
+
+error[E0207]: the const parameter `host` is not constrained by the impl trait, self type, or predicates
+  --> $DIR/derive-const-use.rs:11:6
+   |
+LL | impl const PartialEq for A {
+   |      ^^^^^ unconstrained const parameter
+   |
+   = note: expressions using a const parameter must map each value to a distinct output value
+   = note: proving the result of expressions other than the parameter are unique is not supported
+
 error: const `impl` for trait `Default` which is not marked with `#[const_trait]`
   --> $DIR/derive-const-use.rs:15:16
    |
@@ -37,6 +70,22 @@ error[E0207]: the const parameter `host` is not constrained by the impl trait, s
    = note: expressions using a const parameter must map each value to a distinct output value
    = note: proving the result of expressions other than the parameter are unique is not supported
 
+error: const `impl` for trait `PartialEq` which is not marked with `#[const_trait]`
+  --> $DIR/derive-const-use.rs:15:25
+   |
+LL | #[derive_const(Default, PartialEq)]
+   |                         ^^^^^^^^^
+   |
+   = note: marking a trait with `#[const_trait]` ensures all default method bodies are `const`
+   = note: adding a non-const method body in the future would be a breaking change
+   = note: this error originates in the derive macro `PartialEq` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0207]: the const parameter `host` is not constrained by the impl trait, self type, or predicates
+   |
+   = note: expressions using a const parameter must map each value to a distinct output value
+   = note: proving the result of expressions other than the parameter are unique is not supported
+   = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
+
 error[E0284]: type annotations needed
   --> $DIR/derive-const-use.rs:18:35
    |
@@ -50,16 +99,17 @@ LL | #[derive_const(Default, PartialEq)]
    |                ^^^^^^^ unsatisfied trait bound introduced in this `derive` macro
    = note: this error originates in the derive macro `Default` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error[E0308]: mismatched types
-  --> $DIR/derive-const-use.rs:16:14
+error[E0284]: type annotations needed
+  --> $DIR/derive-const-use.rs:18:23
+   |
+LL | const _: () = assert!(S((), A) == S::default());
+   |                       ^^^^^^^^^^^^^^^^^^^^^^^^ cannot infer the value of the constant `_`
+   |
+note: required for `S` to implement `PartialEq`
+  --> $DIR/derive-const-use.rs:15:25
    |
 LL | #[derive_const(Default, PartialEq)]
-   |                         --------- in this derive macro expansion
-LL | pub struct S((), A);
-   |              ^^ expected `host`, found `true`
-   |
-   = note: expected constant `host`
-              found constant `true`
+   |                         ^^^^^^^^^ unsatisfied trait bound introduced in this `derive` macro
    = note: this error originates in the derive macro `PartialEq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0284]: type annotations needed
@@ -79,7 +129,24 @@ LL | impl const Default for A {
    |      unsatisfied trait bound introduced here
    = note: this error originates in the derive macro `Default` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error: aborting due to 8 previous errors
+error[E0284]: type annotations needed
+  --> $DIR/derive-const-use.rs:16:18
+   |
+LL | #[derive_const(Default, PartialEq)]
+   |                         --------- in this derive macro expansion
+LL | pub struct S((), A);
+   |                  ^ cannot infer the value of the constant `_`
+   |
+note: required for `A` to implement `PartialEq`
+  --> $DIR/derive-const-use.rs:11:12
+   |
+LL | impl const PartialEq for A {
+   |      ----- ^^^^^^^^^     ^
+   |      |
+   |      unsatisfied trait bound introduced here
+   = note: this error originates in the derive macro `PartialEq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-Some errors have detailed explanations: E0207, E0284, E0308, E0635.
+error: aborting due to 14 previous errors; 1 warning emitted
+
+Some errors have detailed explanations: E0207, E0284, E0635.
 For more information about an error, try `rustc --explain E0207`.

tests/ui/rfcs/rfc-2632-const-trait-impl/const_derives/derive-const-with-params.rs

@@ -1,4 +1,5 @@
-//@ check-pass
+//@ known-bug: #110395
+// FIXME(effects) check-pass
 
 #![feature(derive_const)]
 #![feature(const_trait_impl, effects)]

tests/ui/rfcs/rfc-2632-const-trait-impl/const_derives/derive-const-with-params.stderr

@@ -0,0 +1,49 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/derive-const-with-params.rs:5:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+error: const `impl` for trait `PartialEq` which is not marked with `#[const_trait]`
+  --> $DIR/derive-const-with-params.rs:7:16
+   |
+LL | #[derive_const(PartialEq)]
+   |                ^^^^^^^^^
+   |
+   = note: marking a trait with `#[const_trait]` ensures all default method bodies are `const`
+   = note: adding a non-const method body in the future would be a breaking change
+   = note: this error originates in the derive macro `PartialEq` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: `~const` can only be applied to `#[const_trait]` traits
+  --> $DIR/derive-const-with-params.rs:7:16
+   |
+LL | #[derive_const(PartialEq)]
+   |                ^^^^^^^^^
+   |
+   = note: this error originates in the derive macro `PartialEq` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error[E0207]: the const parameter `host` is not constrained by the impl trait, self type, or predicates
+   |
+   = note: expressions using a const parameter must map each value to a distinct output value
+   = note: proving the result of expressions other than the parameter are unique is not supported
+
+error[E0284]: type annotations needed
+  --> $DIR/derive-const-with-params.rs:11:5
+   |
+LL |     a == b
+   |     ^^^^^^ cannot infer the value of the constant `_`
+   |
+note: required for `Reverse<i32>` to implement `PartialEq`
+  --> $DIR/derive-const-with-params.rs:7:16
+   |
+LL | #[derive_const(PartialEq)]
+   |                ^^^^^^^^^ unsatisfied trait bound introduced in this `derive` macro
+   = note: this error originates in the derive macro `PartialEq` (in Nightly builds, run with -Z macro-backtrace for more info)
+
+error: aborting due to 4 previous errors; 1 warning emitted
+
+Some errors have detailed explanations: E0207, E0284.
+For more information about an error, try `rustc --explain E0207`.

tests/ui/rfcs/rfc-2632-const-trait-impl/cross-crate-default-method-body-is-const.rs

@@ -3,7 +3,7 @@
 //
 //@ check-pass
 
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 //@ aux-build: cross-crate.rs
 extern crate cross_crate;

tests/ui/rfcs/rfc-2632-const-trait-impl/cross-crate-default-method-body-is-const.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/cross-crate-default-method-body-is-const.rs:6:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/rfcs/rfc-2632-const-trait-impl/cross-crate.gated.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/cross-crate.rs:3:60
+   |
+LL | #![cfg_attr(any(gated, gatednc), feature(const_trait_impl, effects))]
+   |                                                            ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/rfcs/rfc-2632-const-trait-impl/cross-crate.gatednc.stderr

@@ -1,11 +1,20 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/cross-crate.rs:3:60
+   |
+LL | #![cfg_attr(any(gated, gatednc), feature(const_trait_impl, effects))]
+   |                                                            ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error[E0277]: the trait bound `cross_crate::NonConst: ~const cross_crate::MyTrait` is not satisfied
-  --> $DIR/cross-crate.rs:17:14
+  --> $DIR/cross-crate.rs:18:14
    |
 LL |     NonConst.func();
    |              ^^^^ the trait `~const cross_crate::MyTrait` is not implemented for `cross_crate::NonConst`
    |
    = help: the trait `cross_crate::MyTrait` is implemented for `cross_crate::NonConst`
 
-error: aborting due to 1 previous error
+error: aborting due to 1 previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0277`.

tests/ui/rfcs/rfc-2632-const-trait-impl/cross-crate.rs

@@ -1,6 +1,7 @@
 //@ revisions: stock gated stocknc gatednc
 //@ [gated] check-pass
 #![cfg_attr(any(gated, gatednc), feature(const_trait_impl, effects))]
+//[gated,gatednc]~^ WARN the feature `effects` is incomplete
 
 //@ aux-build: cross-crate.rs
 extern crate cross_crate;

tests/ui/rfcs/rfc-2632-const-trait-impl/cross-crate.stock.stderr

@@ -1,5 +1,5 @@
 error[E0015]: cannot call non-const fn `<cross_crate::Const as cross_crate::MyTrait>::func` in constant functions
-  --> $DIR/cross-crate.rs:20:11
+  --> $DIR/cross-crate.rs:21:11
    |
 LL |     Const.func();
    |           ^^^^^^

tests/ui/rfcs/rfc-2632-const-trait-impl/cross-crate.stocknc.stderr

@@ -1,5 +1,5 @@
 error[E0015]: cannot call non-const fn `<cross_crate::NonConst as cross_crate::MyTrait>::func` in constant functions
-  --> $DIR/cross-crate.rs:17:14
+  --> $DIR/cross-crate.rs:18:14
    |
 LL |     NonConst.func();
    |              ^^^^^^
@@ -11,7 +11,7 @@ LL + #![feature(const_trait_impl)]
    |
 
 error[E0015]: cannot call non-const fn `<cross_crate::Const as cross_crate::MyTrait>::func` in constant functions
-  --> $DIR/cross-crate.rs:20:11
+  --> $DIR/cross-crate.rs:21:11
    |
 LL |     Const.func();
    |           ^^^^^^

tests/ui/rfcs/rfc-2632-const-trait-impl/default-method-body-is-const-same-trait-ck.rs

@@ -1,4 +1,4 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 #[const_trait]
 pub trait Tr {

tests/ui/rfcs/rfc-2632-const-trait-impl/default-method-body-is-const-same-trait-ck.stderr

@@ -1,3 +1,12 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/default-method-body-is-const-same-trait-ck.rs:1:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error[E0277]: the trait bound `(): ~const Tr` is not satisfied
   --> $DIR/default-method-body-is-const-same-trait-ck.rs:8:12
    |
@@ -6,6 +15,6 @@ LL |         ().a()
    |
    = help: the trait `Tr` is implemented for `()`
 
-error: aborting due to 1 previous error
+error: aborting due to 1 previous error; 1 warning emitted
 
 For more information about this error, try `rustc --explain E0277`.

tests/ui/rfcs/rfc-2632-const-trait-impl/do-not-const-check-override.rs

@@ -1,5 +1,5 @@
 //@ check-pass
-#![feature(const_trait_impl, rustc_attrs, effects)]
+#![feature(const_trait_impl, rustc_attrs, effects)] //~ WARN the feature `effects` is incomplete
 
 #[const_trait]
 trait Foo {

tests/ui/rfcs/rfc-2632-const-trait-impl/do-not-const-check-override.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/do-not-const-check-override.rs:2:43
+   |
+LL | #![feature(const_trait_impl, rustc_attrs, effects)]
+   |                                           ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/auxiliary/cross-crate.rs

@@ -1,4 +1,4 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 pub const fn foo() {}
 

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/effect-param-infer.rs

@@ -3,7 +3,7 @@
 //
 //@ check-pass
 
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 #[const_trait]
 pub trait Foo<Rhs: ?Sized = Self> {

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/effect-param-infer.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/effect-param-infer.rs:6:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/fallback.rs

@@ -1,6 +1,6 @@
 //@ check-pass
 
-#![feature(effects)]
+#![feature(effects)] //~ WARN the feature `effects` is incomplete
 
 pub const fn owo() {}
 

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/fallback.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/fallback.rs:3:12
+   |
+LL | #![feature(effects)]
+   |            ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/helloworld.rs

@@ -3,7 +3,12 @@
 // gate-test-effects
 // ^ effects doesn't have a gate so we will trick tidy into thinking this is a gate test
 
-#![feature(const_trait_impl, effects, core_intrinsics, const_eval_select)]
+#![feature(
+    const_trait_impl,
+    effects, //~ WARN the feature `effects` is incomplete
+    core_intrinsics,
+    const_eval_select
+)]
 
 // ensure we are passing in the correct host effect in always const contexts.
 

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/helloworld.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/helloworld.rs:8:5
+   |
+LL |     effects,
+   |     ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/ice-112822-expected-type-for-param.rs

@@ -1,16 +1,15 @@
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 const fn test() -> impl ~const Fn() {
     //~^ ERROR `~const` can only be applied to `#[const_trait]` traits
     //~| ERROR `~const` can only be applied to `#[const_trait]` traits
-    //~| ERROR cycle detected
     const move || { //~ ERROR const closures are experimental
         let sl: &[u8] = b"foo";
 
         match sl {
             [first, remainder @ ..] => {
                 assert_eq!(first, &b'f');
-                //~^ ERROR can't compare `&u8` with `&u8`
+                //~^ ERROR cannot call non-const fn
             }
             [] => panic!(),
         }

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/ice-112822-expected-type-for-param.stderr

@@ -1,5 +1,5 @@
 error[E0658]: const closures are experimental
-  --> $DIR/ice-112822-expected-type-for-param.rs:7:5
+  --> $DIR/ice-112822-expected-type-for-param.rs:6:5
    |
 LL |     const move || {
    |     ^^^^^
@@ -8,6 +8,15 @@ LL |     const move || {
    = help: add `#![feature(const_closures)]` to the crate attributes to enable
    = note: this compiler was built on YYYY-MM-DD; consider upgrading it if it is out of date
 
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/ice-112822-expected-type-for-param.rs:1:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
 error: `~const` can only be applied to `#[const_trait]` traits
   --> $DIR/ice-112822-expected-type-for-param.rs:3:32
    |
@@ -22,47 +31,16 @@ LL | const fn test() -> impl ~const Fn() {
    |
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
 
-error[E0277]: can't compare `&u8` with `&u8`
-  --> $DIR/ice-112822-expected-type-for-param.rs:12:17
+error[E0015]: cannot call non-const fn `core::panicking::assert_failed::<&u8, &u8>` in constant functions
+  --> $DIR/ice-112822-expected-type-for-param.rs:11:17
    |
 LL |                 assert_eq!(first, &b'f');
-   |                 ^^^^^^^^^^^^^^^^^^^^^^^^ no implementation for `&u8 == &u8`
+   |                 ^^^^^^^^^^^^^^^^^^^^^^^^
    |
-   = help: the trait `~const PartialEq<&u8>` is not implemented for `&u8`
+   = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants
    = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
-error[E0391]: cycle detected when computing type of opaque `test::{opaque#0}`
-  --> $DIR/ice-112822-expected-type-for-param.rs:3:20
-   |
-LL | const fn test() -> impl ~const Fn() {
-   |                    ^^^^^^^^^^^^^^^^
-   |
-note: ...which requires borrow-checking `test`...
-  --> $DIR/ice-112822-expected-type-for-param.rs:3:1
-   |
-LL | const fn test() -> impl ~const Fn() {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires promoting constants in MIR for `test`...
-  --> $DIR/ice-112822-expected-type-for-param.rs:3:1
-   |
-LL | const fn test() -> impl ~const Fn() {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-note: ...which requires const checking `test`...
-  --> $DIR/ice-112822-expected-type-for-param.rs:3:1
-   |
-LL | const fn test() -> impl ~const Fn() {
-   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   = note: ...which requires computing whether `test::{opaque#0}` is freeze...
-   = note: ...which requires evaluating trait selection obligation `test::{opaque#0}: core::marker::Freeze`...
-   = note: ...which again requires computing type of opaque `test::{opaque#0}`, completing the cycle
-note: cycle used when computing type of `test::{opaque#0}`
-  --> $DIR/ice-112822-expected-type-for-param.rs:3:20
-   |
-LL | const fn test() -> impl ~const Fn() {
-   |                    ^^^^^^^^^^^^^^^^
-   = note: see https://rustc-dev-guide.rust-lang.org/overview.html#queries and https://rustc-dev-guide.rust-lang.org/query.html for more information
+error: aborting due to 4 previous errors; 1 warning emitted
 
-error: aborting due to 5 previous errors
-
-Some errors have detailed explanations: E0277, E0391, E0658.
-For more information about an error, try `rustc --explain E0277`.
+Some errors have detailed explanations: E0015, E0658.
+For more information about an error, try `rustc --explain E0015`.

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/infer-fallback.rs

@@ -1,5 +1,5 @@
 //@ check-pass
-#![feature(const_trait_impl, effects)]
+#![feature(const_trait_impl, effects)] //~ WARN the feature `effects` is incomplete
 
 const fn a() {}
 

tests/ui/rfcs/rfc-2632-const-trait-impl/effects/infer-fallback.stderr

@@ -0,0 +1,11 @@
+warning: the feature `effects` is incomplete and may not be safe to use and/or cause compiler crashes
+  --> $DIR/infer-fallback.rs:2:30
+   |
+LL | #![feature(const_trait_impl, effects)]
+   |                              ^^^^^^^
+   |
+   = note: see issue #102090 <https://github.com/rust-lang/rust/issues/102090> for more information
+   = note: `#[warn(incomplete_features)]` on by default
+
+warning: 1 warning emitted
+