On Sun, Mar 18, 2018 at 10:17:41AM +0100, Duy Nguyen wrote:
> On Sun, Mar 18, 2018 at 10:06 AM, Eric Sunshine <sunshine@xxxxxxxxxxxxxx> wrote:
> > On Sun, Mar 18, 2018 at 09:18:34AM +0100, Nguyễn Thái Ngọc Duy wrote:
> >> The set of extra warnings we enable when DEVELOPER has to be
> >> conservative because we can't assume any compiler version the
> >> developer may use. Detect the compiler version so we know when it's
> >> safe to enable -Wextra and maybe more.
> >>
> >> Helped-by: Jeff King <peff@xxxxxxxx>
> >> Signed-off-by: Nguyễn Thái Ngọc Duy <pclouds@xxxxxxxxx>
> >> ---
> >> diff --git a/detect-compiler b/detect-compiler
> >> --- /dev/null
> >> +++ b/detect-compiler
> >> @@ -0,0 +1,50 @@
> >> +get_version_line() {
> >> + "$CC" -v 2>&1 | grep ' version '
> >> +}
> >
> > On MacOS, "cc -v" output is:
> >
> > --- >8 ---
> > Apple LLVM version 9.0.0 (clang-900.0.39.2)
> > Target: x86_64-apple-darwin16.7.0
> > Thread model: posix
> > InstalledDir: ...
> > --- >8 ---
>
> Does it still build ok for you with your changes squashed in? I think
> the check for clang4/gcc6 and setting -Wextra in config.mak.dev may
> backfire because clang9 probably has a lot more warnings enabled and
> some of them we don't want and cause compile error...
I don't think we can predict that going forward, though. We'd have to
wait for people to use the new compiler and then send a patch disabling
whatever causes a problem (or better yet, fixing the code if
appropriate).
This framework can only help us write those patches; I don't think it
can save us from having to do them in the first place.
-Peff
