[Ffmpeg-devel] build systems

[Dave Dodge]

On Tue, Sep 20, 2005 at 01:36:58PM +0100, M?ns Rullg?rd wrote:
> Attila Kinali said:
> > Then why hasn't anyone written a replacement yet?
> 
> It would take time and effort.

Yes, consider that autoconf has been around for over a decade and has
accumulated a lot of knowledge about obscure systems most people
haven't even heard of.  That's it's strength.  It presents a common
front-end for configuration, which from a user standpoint is a
godsend.  It makes scripted builds very simple.

...but then so does pretty much any configuration system that calls
itself "configure" and understands at least the --prefix and --help
options.  From a user standpoint, as long as I see that I'm usually
happy.  I do remember the days of having to hand-edit headers and
Makefiles in some unique way for every build tree; autotools made that
mostly go away, for which I am thankful.

Where autotools falls down (this is from an end-user viewpoint, not a
maintainer viewpoint):

  - Some projects have multiple configure scripts in subdirectories.
    This is a pain because it takes so much longer to build and
    experiment with configure settings.  It also makes
    hacking/overriding the configure script very complicated.

  - I've seen build trees that insisted on re-running the configure
    script every time you did a "make".  I consider this broken.

  - Libtool bloat.  Example: a few years ago I compiled Mozilla.  At
    the time the final executable was around 16M in size.  The
    compilation however consumed 1.5 _gigabytes_ of disk space.  For a
    16M executable.  This is completely absurd, and I believe libtool
    or perhaps some specific way of using it is the cause.

  - Libtool failures.  Be VERY thankful that this is rare, because
    debugging libtool output is ten thousand times worse than anything
    you might find in a configure script or Makefile.  If you've never
    been face-to-face with this monster, be very glad; if you have
    been, you're probably cursing at it under your breath as you read
    this.  My most recent encounter was in July, and I'm still sore
    from it.

                                                  -Dave Dodge