/** Record that a warning is about to be issued, and treat it as an
error if <tt>warnings_flag & warnings_error</tt>. This is exported
only for the sake of Yacc-compatible conflict reports in conflicts.c.
/** Record that a warning is about to be issued, and treat it as an
error if <tt>warnings_flag & warnings_error</tt>. This is exported
only for the sake of Yacc-compatible conflict reports in conflicts.c.