error: const `impl` for trait `Foo` which is not marked with `#[const_trait]`
  --> $DIR/spec-effectvar-ice.rs:10:15
   |
LL | impl<T> const Foo for T {}
   |               ^^^ this trait is not `const`
   |
   = 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
help: mark `Foo` as `#[const_trait]` to allow it to have `const` implementations
   |
LL | #[const_trait] trait Foo {}
   | ++++++++++++++

error: const `impl` for trait `Foo` which is not marked with `#[const_trait]`
  --> $DIR/spec-effectvar-ice.rs:13:15
   |
LL | impl<T> const Foo for T where T: const Specialize {}
   |               ^^^ this trait is not `const`
   |
   = 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
help: mark `Foo` as `#[const_trait]` to allow it to have `const` implementations
   |
LL | #[const_trait] trait Foo {}
   | ++++++++++++++

error: `const` can only be applied to `#[const_trait]` traits
  --> $DIR/spec-effectvar-ice.rs:13:34
   |
LL | impl<T> const Foo for T where T: const Specialize {}
   |                                  ^^^^^ can't be applied to `Specialize`
   |
help: mark `Specialize` as `#[const_trait]` to allow it to have `const` implementations
   |
LL | #[const_trait] trait Specialize {}
   | ++++++++++++++

error: specialization impl does not specialize any associated items
  --> $DIR/spec-effectvar-ice.rs:13:1
   |
LL | impl<T> const Foo for T where T: const Specialize {}
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
note: impl is a specialization of this impl
  --> $DIR/spec-effectvar-ice.rs:10:1
   |
LL | impl<T> const Foo for T {}
   | ^^^^^^^^^^^^^^^^^^^^^^^

error: cannot specialize on trait `Specialize`
  --> $DIR/spec-effectvar-ice.rs:13:34
   |
LL | impl<T> const Foo for T where T: const Specialize {}
   |                                  ^^^^^^^^^^^^^^^^

error: aborting due to 5 previous errors