1 error[E0277]: expected a `Fn<()>` closure, found `extern "C" fn() {f}`
2 --> $DIR/extern-wrong-value-type.rs:9:11
5 | ----- ^ expected an `Fn<()>` closure, found `extern "C" fn() {f}`
7 | required by a bound introduced by this call
9 = help: the trait `Fn<()>` is not implemented for fn item `extern "C" fn() {f}`
10 = note: wrap the `extern "C" fn() {f}` in a closure with no arguments: `|| { /* code */ }`
11 note: required by a bound in `is_fn`
12 --> $DIR/extern-wrong-value-type.rs:4:28
14 LL | fn is_fn<F>(_: F) where F: Fn() {}
15 | ^^^^ required by this bound in `is_fn`
17 error: aborting due to previous error
19 For more information about this error, try `rustc --explain E0277`.