R3. It is recommended that each package adopt and document a consistent system for propagating/returning error conditions/exceptions and provide an API for changing the behavior. For example, all routines may, by default, return an error code with the option of changing it to generate an abort on the error (for running in the debugger). No package should have hardwired calls to abort, exit, or MPI_Abort(). Also, no package should have hardwired print statements for error conditions. Each package should document which error codes/exceptions are recoverable, which may result in lost resources (for example, unfreed memory), and which indicate that the process may be in an undefined or totally broken state (for example, after a segmentation violation). It is the responsibility of the calling routine not to simply continue the computation when a “hard” error is returned; the calling routine will likely, by default, call an abort, but again that should be possible to override.