Macro warn_report 

macro_rules! warn_report {
    ($err:expr) => { ... };
    ($err:expr, $($rest:tt)*) => { ... };
}

Log a report for err at level WARN

Examples:

use tor_error::warn_report;
warn_report!(err, "Cheese exhausted (ephemeral)");
warn_report!(err, "Unable to parse message {:?}", msg);