val report : ?extra:(Stdune.Loc.t option -> Stdune.User_message.Style.t Stdune.Pp.t option) -> Stdune.Exn_with_backtrace.t -> unit
Reports an error.
Because dune doesn't stop at the first error, it might end up reporting the same error twice about missing libraries for instance. To avoid this, we keep a cache of reported errors and ignore errors that have already been reported.
We cache what is actually printed to the screen.
extra
is the extra material that is printed between the backtrace and the hint.
Raised for errors that have already been reported to the user and shouldn't be reported again. This might happen when trying to build a dependency that has already failed.