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

error: using `#![feature(effects)]` without enabling next trait solver globally
   |
   = note: the next trait solver must be enabled globally for the effects feature to work correctly
   = help: use `-Znext-solver` to enable

error: cannot specialize on const impl with non-const impl
  --> $DIR/specializing-constness.rs:23:1
   |
LL | impl<T: Spec + Sup> A for T {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^

error: cannot specialize on trait `Compat`
  --> $DIR/specializing-constness.rs:23:16
   |
LL | impl<T: Spec + Sup> A for T {
   |                ^^^

error: cannot specialize on trait `Compat`
  --> $DIR/specializing-constness.rs:23:9
   |
LL | impl<T: Spec + Sup> A for T {
   |         ^^^^

error: aborting due to 4 previous errors; 1 warning emitted