automake version (am__api_version) hardcoded in configure script

Question

I'm currently working on a Linux project using autotools. The code is submitted in SCM (Perforce) and we have the configure script, Makefile.am, Makefile.in - the usual autotools boilerplate. Recently, somebody has changed Makefile.am, but forgot to regenerate Makefile.in; when I tried to build, I got this error:

WARNING: `automake-1.11' is missing on your system.  You should only need it if
         you modified `Makefile.am', `acinclude.m4' or `configure.ac'.
         You might want to install the `Automake' and `Perl' packages.
         Grab them from any GNU archive site.
 cd . && /bin/bash ./config.status Makefile depfiles

I see the automake version is hardcoded in the configure script (and seems to come from aclocal.m4):

am__api_version='1.11'

So I guess I need automake-1.11 (not 1.10, not anything newer) to regenerate the Makefile.in file.

Why is that? Why should we be tied to a specific automake version? We're mostly building on Ubuntu 14.04, where 1.14 is the default version installed. Is there a way to tell the build system to simply use whatever version of automake is installed? Or is it safe to maybe remove the am__api_version definition from aclocal.m4?

Answer 1

The problem is that you are trying to recreate Makefile.in with other version of autotools. It would lead to version mismatch as aclocal.m4 was built with different version and it is used to generate the remaining files.

Instead of recreating only Makefile.in, try to also recreate aclocal.m4 and all remaining autotools generated files:

autoreconf --force --install