error[E0391]: cycle detected when simplifying constant for the type system `Y::A::{constant#0}` --> $DIR/issue-23302-2.rs:4:9 | LL | A = Y::B as isize, | ^^^^^^^^^^^^^ | note: ...which requires const-evaluating + checking `Y::A::{constant#0}`... --> $DIR/issue-23302-2.rs:4:9 | LL | A = Y::B as isize, | ^^^^^^^^^^^^^ = note: ...which again requires simplifying constant for the type system `Y::A::{constant#0}`, completing the cycle note: cycle used when simplifying constant for the type system `Y::A::{constant#0}` --> $DIR/issue-23302-2.rs:4:9 | LL | A = Y::B as isize, | ^^^^^^^^^^^^^ = 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 previous error For more information about this error, try `rustc --explain E0391`.