error[E0015]: cannot call non-const fn `_print` in constant functions --> $DIR/issue-79450.rs:9:9 | LL | println!("lul"); | ^^^^^^^^^^^^^^^ | = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants = note: this error originates in the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info) error: aborting due to 1 previous error For more information about this error, try `rustc --explain E0015`.