[vlc-devel] [PATCH 1/2] configure: add an option to turn some dangerous warnings into errors

[Rémi Denis-Courmont]

Le perjantaina 20. maaliskuuta 2020, 11.20.49 EET Steve Lhomme a écrit :
> Mismatching pointers are usually a result of using the incorrect pointer and
> might trigger crashes.
> 
> Missing initializers are useful for structures of callbacks, to make sure a
> new callback is not missing by accident. It's always possible to put NULL,
> on purpose, knowingly.
> 
> Both flags produce no error on win32/win64 with clang or gcc. But they
> cannot be set globally outside of the build script as many contribs will
> likely fail these tests and we shouldn't refuse/patch a contrib just for
> that.
> 
> I have been compiling with these flags for weeks without issues. It helped
> find some issue (48442d3536edae578f1a384e73346d1e2a4c0061) that were pushed
> unnoticed without these checks.
> ---
>  configure.ac | 6 ++++++
>  1 file changed, 6 insertions(+)
> 
> diff --git a/configure.ac b/configure.ac
> index bc1874cb97c..c96b3fe6fac 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -4480,6 +4480,12 @@ AS_VAR_IF(with_libfuzzer, no, [], [
>      ])
>  ])
> 
> +AC_ARG_ENABLE([extra-checks],
> +  AS_HELP_STRING([--enable-extra-checks],
> +         [Turn some compilation warnings into errors]), [
> +  AX_APPEND_COMPILE_FLAGS([-Werror=incompatible-pointer-types
> -Werror=missing-field-initializers], [CFLAGS]) +])

I don't see what justifies adding yet another option here. In this case, you 
can just as well pass them with CFLAGS/CXXFLAGS like everybody and everything 
else does.

-- 
Rémi Denis-Courmont
http://www.remlab.net/