src/test/ui/unwind-abis/feature-gate-c-unwind.rs

// Test that the "C-unwind" ABI is feature-gated, and cannot be used when the
// `c_unwind` feature gate is not used.

extern "C-unwind" fn f() {}
//~^ ERROR C-unwind ABI is experimental and subject to change [E0658]

fn main() {
    f();
}