warning: Panic message contains a brace
  --> $DIR/panic-brace.rs:5:5
   |
LL |     panic!("here's a brace: {");
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: `#[warn(panic_fmt)]` on by default
   = note: This message is not used as a format string, but will be in a future Rust version
help: add a "{}" format string to use the message literally
   |
LL |     panic!("{}", "here's a brace: {");
   |            ^^^^^

warning: Panic message contains a brace
  --> $DIR/panic-brace.rs:6:5
   |
LL |     std::panic!("another one: }");
   |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: This message is not used as a format string, but will be in a future Rust version
help: add a "{}" format string to use the message literally
   |
LL |     std::panic!("{}", "another one: }");
   |                 ^^^^^

warning: Panic message contains an unused formatting placeholder
  --> $DIR/panic-brace.rs:7:18
   |
LL |     core::panic!("Hello {}");
   |                  ^^^^^^^^^^
   |
   = note: This message is not used as a format string when given without arguments, but will be in a future Rust version
help: add the missing argument(s)
   |
LL |     core::panic!("Hello {}", argument);
   |                            ^^^^^^^^^^
help: or add a "{}" format string to use the message literally
   |
LL |     core::panic!("{}", "Hello {}");
   |                  ^^^^^

warning: Panic message contains an unused formatting placeholder
  --> $DIR/panic-brace.rs:8:20
   |
LL |     assert!(false, "{:03x} bla");
   |                    ^^^^^^^^^^^^
   |
   = note: This message is not used as a format string when given without arguments, but will be in a future Rust version
help: add the missing argument(s)
   |
LL |     assert!(false, "{:03x} bla", argument);
   |                                ^^^^^^^^^^
help: or add a "{}" format string to use the message literally
   |
LL |     assert!(false, "{}", "{:03x} bla");
   |                    ^^^^^

warning: 4 warnings emitted