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)] | ^^^^^^^^^ 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 error: `~const` can only be applied to `#[const_trait]` traits | note: `PartialEq` can't be used with `~const` because it isn't annotated with `#[const_trait]` --> $SRC_DIR/core/src/cmp.rs:LL:COL error[E0015]: cannot call non-const operator in constant functions --> $DIR/derive-const-with-params.rs:8:23 | LL | #[derive_const(PartialEq)] | --------- in this derive macro expansion LL | pub struct Reverse(T); | ^ | = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants error[E0015]: cannot call non-const operator in constant functions --> $DIR/derive-const-with-params.rs:11:5 | LL | a == b | ^^^^^^ | = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants error: aborting due to 4 previous errors For more information about this error, try `rustc --explain E0015`.