So the new version of Automake is out, and is most likely going to be the last release of the first major version. The next version of Automake is going to be 2.0, not to be confused with Automake NG which is a parallel project, still maintained by Stefano, but with a slightly different target.
After the various issues in 1.13 series Stefano decided to take a much more conservative approach for both 1.14 and the upcoming 2.0. While a bunch of features are getting deprecated with these two versions, they will not be dropped at least until version 3.0 I suppose. This mean that there should be all the time for developers to update their Autotools before they starting failing. Users of -Werror for Automake will of course still see issues, but I’ve already written about it so I’m not going back on the topic.
There are no big deals with the new release, by the way, as its topic seems to be mostly “get things straight”. For instance, the C compilation handling has been streamlined, with anticipation of further streamlining on Automake 2.0. In particular, the next major release will get rid of the subdir-objects option… by force-enabling it, which also means that the connected, optional AM_PROG_CC_C_O is now bolted on the basic AC_PROG_CC. What does this mean? Mostly that there is one fewer line to add to your configure.ac when you use subdir-objects, and if you don’t use subdir-objects today, you should. It also means that the compile script is now needed by all automake projects.
The only one new feature that I think is worth the release, is better support for including files within Makefile.am — this allows the creation of almost independent “module” files so that your build rules still live with the source files, but the final result is non-recursive. The changes make Karel’s way much more practical, to the point I’ve actually started writing documentation for it in Autotools Mythbuster.
# src/Makefile.inc
bin_PROGRAMS += myprog
man_MANS += %D%/myprog.8
myprog_SOURCES = %D%/myprog.c
%D%/myprog-utils.c
The idea is that instead of knowing exactly what your subdirectory is that contains the sources, you can simply use %D% (or reldir) and then you can move said directory around. It makes it possible to properly handle a bundled-but-optout-capable library so that you don’t have to fight too much with the build system. I think that’ll actuall be the next post in the Autotools Mythbuster series, how to create a library project with a clear bundling path and, at the same time, the ability to use the system copy of the library itself.
Anyway, let’s all thank Stefano for a likely uneventful automake release. Autotools Mythbuster is being updated, for now you can find up to date forward porting notes but before coming back from vacation I’ll most likely update a few more sections.