Since the introduction of the testing SCons-based build system to the Battle for Wesnoth project, I have been annoyed repeteadly by its decreased performance in comparison with the old autotools based system we were using, and its increased power consumption in my laptop.
I felt alone in this world... since March IIRC, until I stumbled upon our Debian packager's blog entry about it just yesterday. *grin*
I cannot deny that Loonycyborg and ESR have done a great job in making the SCons build recipe for Wesnoth better over time, but there are these tiny issues that they cannot overcome without modifying SCons' source code itself and requesting all our users to use a patched version of SCons for that. Nonetheless, it annoys me that users have to install a non-GNU tool to be able to even see the build options for the software. This is certainly one of the good things about autotools: you generate the processed recipe and it will run on any machine with the UNIX or GNU coreutils, a compatible sh* and make! Of course, assuming the author of the raw recipe (configure.ac/in and friends) did not use what is called "bad practice" in it (bashisms, silent environment requirements, etc.). I still have to find a processed autotools recipe (Makefile.in, configure) that fails to run and do its job from a released source code distribution in any FLOSS project.
So with autotools it is rarely needed to install the recipe-processor tools (aclocal, autoconf, automake, autoheader, autopoint) if one wants to run software, not develop it. Yet with SCons and... CMake (the other candidate replacement for autotools at Wesnoth), it is necessary to install the equivalent of Apache server in the client machines for the equivalent of downloading a set of files from a public area of the server. Why?
That said, I'm personally sticking to autotools for managing builds (and have fun tailoring them to temporary needs at times!) in my personal project, Mesiga, until the GNU project comes with a better solution... should that be possible. Moreover, I'd personally maintain the autotools recipe in Wesnoth if our Release Manager wouldn't have been so persistent in the "let it rot" policy.
The fact that SCons project's homepage is filled with propaganda from big people in the software industry such as iD Software and ESR, is even more disturbing for me. It makes me think it... it... IT IS A TRAP! The "What makes SCons better?" section is fearsome... to me it looks like 'featuritis'. There are so many features built into SCons that they are overwhelming to me. Why users have to install this big piece of software in their machines if they just want to build some software, I mean?
And this question has haunted me in nightmares for quite a few months already... because of that, I have been sleeping less than 6 hours a day, so no wonder if I'm writing nonsense here.
Thanks goodness they didn't make adding new source code files to targets harder than with autotools.