[PATCH] Show dangerous warning when -Werror option is used

[Marek Polacek]

On Sun, Apr 01, 2018 at 12:05:40PM +0200, Pali Rohár wrote:
> Command line option -Werror is dangerous as it could cause problems for
> compiling applications in future. Once gcc introduces a new warning or
> change logic for existing warnings then compilation of existing
> application via gcc could throw a new warning.
> 
> As -Werror makes all warnings fatal, it makes applications not
> compilable. -Werror makes sense only for specific gcc versions against
> which was application tested to compile correctly.
> 
> Attached patch adds a new warning when -Werror command line option is
> enabled. It warns user that usage of -Werror can be dangerous.

While I don't think that enabling -Werror for release builds is a good idea,
I disagree that we should warn about using it.

	Marek