I feel like it would be beneficial to enable +partial-match (warning 8) as an error by default for ocamlopt and ocamlc (but not in the toplevel because it's useful for quick testing purpose).

Take for example a library a, which provides a parser for a certain format. If the library adds a new node to the AST or splits an existing node into 2, consumers of the library might not notice their code is half broken until it break at runtime, or even in more mysterious ways if the exception that triggered happened to have been caught by a misplaced try ... with _ -> ....

Apologies if that has already been proposed somewhere, i couldn't find any discussion related to this in the issue tracker.