[arch-general] Enforcing CFLAGS in PKGBUILDs

[Lukas Fleischer]

On Fri, Aug 05, 2011 at 03:23:44PM +0800, Ray Rashif wrote:
> On 5 August 2011 07:35, Lukas Fleischer <archlinux at cryptocrack.de> wrote:
> > My own opinion is that we shouldn't patch anything here. While using the
> > same optimization flags for all packages might result in some kind of
> > consistency, one of our main guidelines - not to do any unnecessary
> > modifications - is kind of violated here. We should trust upstream
> > having chosen any explicit optimization flags with care (in some cases,
> > enforcing optimization flags might even lead to heavy performance
> > impacts - although this is unlikely to happen). I am aware that there
> > are some corner cases for sure, for which I'd say overriding CFLAGS is
> > okay. However, this shouldn't be common practice, imho.
> >
> > Opinions?
> 
> I have wondered about this before. Upstream developers should include
> in their code/buildsystem proper conditional CFLAGS, i.e append to
> system CFLAGS, override _only_ what they want to override, and don't
> append anything already part of the system CFLAGS.
> 
> For eg. some developers like to enforce -O3, so they should first get
> the system CFLAGS and override it's -O*, if any.

Well, just appending their own flags (which is what most Makefiles do)
is no problem here as only the last "-O" option will matter (check my
reply to Allan).

> 
> But in general, I agree. We shouldn't enforce anything either unless
> we're trying to fix something.

+1.

> The ardour PKGBUILD does this [1], maybe it shouldn't, but I assume
> the -O3 becomes redundant when we pass system CFLAGS to the build as a
> configuration flag.

Yeah, I agree that patching is okay if it's necessary in order to build
a package (or in order not to break anything). That's what I mentioned
above.