buildtools.git

   acconfig.h       configure.in                 Makefile.am
       |                |                           |
       |  --------------+----------------------     |
       |  |             |                     |     |
       v  v             |    acinclude.m4     |     |
   *autoheader*         |         |           v     v
       |                |         v      --->*automake* 
       v                |--->*aclocal*   |       |      
   config.in            |         |      |       v      
                        |         v      |   Makefile.in
                        |    aclocal.m4---
                        |     |
                        v     v
                       *autoconf*
                           |
                           v
                       configure