error[E0015]: cannot call non-const operator in constant functions --> $DIR/generic-bound.rs:25:5 | LL | arg + arg | ^^^^^^^^^ | note: impl defined here, but it is not `const` --> $DIR/generic-bound.rs:16:1 | LL | impl const std::ops::Add for S { | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants = help: add `#![feature(effects)]` to the crate attributes to enable error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0015`.