Since the following commit ...

commit 73ab254336100c5971e3a1e14b73222efd0e9822
Author: Akira TAGOH <akira@tagoh.org>
Date:   Tue Oct 23 15:52:37 2012 +0900

    autogen.sh: Add -I option to tell aclocal a place for external m4 files


... bootstrapping in a clean git checkout fails:

sam@droopy:~/build/src/fontconfig $ ./autogen.sh 
I am going to run ./configure with no arguments - if you wish 
to pass any to it, please specify them on the ./autogen.sh command line.
Running aclocal -I m4
aclocal: couldn't open directory 'm4': No such file or directory


Creating the directory fixes the problem. It would make life easier for people who build directly from git if this directory could be present in the git tree to prevent the error. Since git doesn't track empty directories, it would need a dummy file inside too. Another option would be to add 'mkdir -p m4' to the top of autogen.sh.

Thanks!