error: const `impl` for trait `FromResidual` which is not marked with `#[const_trait]`
  --> $DIR/ice-119717-constant-lifetime.rs:6:15
   |
LL | impl<T> const FromResidual for T {
   |               ^^^^^^^^^^^^
   |
   = 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[E0210]: type parameter `T` must be used as the type parameter for some local type (e.g., `MyStruct<T>`)
  --> $DIR/ice-119717-constant-lifetime.rs:6:6
   |
LL | impl<T> const FromResidual for T {
   |      ^ type parameter `T` must be used as the type parameter for some local type
   |
   = note: implementing a foreign trait is only possible if at least one of the types for which it is implemented is local
   = note: only traits defined in the current crate can be implemented for a type parameter

error[E0121]: the placeholder `_` is not allowed within types on item signatures for functions
  --> $DIR/ice-119717-constant-lifetime.rs:9:31
   |
LL |     fn from_residual(t: T) -> _ {
   |                               ^ not allowed in type signatures
   |
help: try replacing `_` with the type in the corresponding trait method signature
   |
LL |     fn from_residual(t: T) -> T {
   |                               ~

error: aborting due to 3 previous errors

Some errors have detailed explanations: E0121, E0210.
For more information about an error, try `rustc --explain E0121`.