error[E0015]: cannot call non-const fn `regular_in_block` in constant functions --> $DIR/const-extern-fn-call-extern-fn.rs:9:9 | LL | regular_in_block(); | ^^^^^^^^^^^^^^^^^^ | = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants error[E0015]: cannot call non-const fn `regular` in constant functions --> $DIR/const-extern-fn-call-extern-fn.rs:18:9 | LL | regular(); | ^^^^^^^^^ | = note: calls in constant functions are limited to constant functions, tuple structs and tuple variants error: aborting due to 2 previous errors For more information about this error, try `rustc --explain E0015`.