rust/tests/ui/check-cfg/invalid-arguments.unsafe_attr.stderr

error: invalid `--check-cfg` argument: `unsafe(cfg(foo))`
   |
   = note: expected `cfg(name, values("value1", "value2", ... "valueN"))`
   = note: visit <https://doc.rust-lang.org/nightly/rustc/check-cfg.html> for more details