Re: Suggestion: add -pipe to default buildflags

[Guillem Jover <guillem@debian.org>]

Hi!

On Tue, 2012-06-05 at 13:54:30 +0300, Serge wrote:
> Recent discussion in debian-devel shows that there're people who care about
> small /tmp-files created by gcc without -pipe option.
> 
> Suggestion: add the -pipe option to default dpkg build flags:
> CFLAGS, CXXFLAGS and FFLAGS. I.e. instead of "-g -O2" use "-g -O2 -pipe"
> 
> It can make things faster, in theory. Can it break anything?

It's been known to break in the past (ICE), but that should be fixed
by now. It will break if the platform assembler does not support
getting the files through pipes, but that should not affect GNU
systems (although dpkg works on other non-GNU systems). It's said to
use “way” more memory than w/o. Possibly other issues given that it's
not gcc's default.

So before considering adding it by default, I'd like the following
things done (these should actually be in general the guidelines to
follow when proposing a new flag added to the default):

 * A test rebuild of the whole archive w/ and w/o, and a comparison
   to see if there's no difference in the amount built.
 * A comparison of the build logs to see the memory and build time
   difference (sbuild should provides those).
 * Once these are done, and if it still seems worth it, a discussion
   started in debian-devel proposing the change, asking if there's
   other known issues, concerns, etc.

thanks,
guillem