// run-fail // check-run-results // exec-env:RUST_BACKTRACE=0 // Test that we format the panic message only once. // Regression test for https://github.com/rust-lang/rust/issues/110717 use std::fmt; struct PrintOnFmt; impl fmt::Display for PrintOnFmt { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { eprintln!("fmt"); f.write_str("PrintOnFmt") } } fn main() { panic!("{}", PrintOnFmt) }