Automake generates rules to automatically rebuild Makefiles, configure, and other derived files like Makefile.in.
If you are using
AM_MAINTAINER_MODE in configure.ac, then
these automatic rebuilding rules are only enabled in maintainer mode.
Sometimes it is convenient to supplement the rebuild rules for
configure or config.status with additional dependencies.
CONFIG_STATUS_DEPENDENCIES can be used to list these extra
dependencies. These variables should be defined in all
Makefiles of the tree (because these two rebuild rules are
output in all them), so it is safer and easier to
from configure.ac. For instance, the following statement will
cause configure to be rerun each time version.sh is
Note the ‘$(top_srcdir)/’ in the file name. Since this variable is to be used in all Makefiles, its value must be sensible at any level in the build hierarchy.
Beware not to mistake
CONFIGURE_DEPENDENCIES adds dependencies to the
configure rule, whose effect is to run autoconf. This
variable should be seldom used, because automake already tracks
m4_included files. However it can be useful when playing
tricky games with
m4_esyscmd or similar non-recommendable
macros with side effects. Be also aware that interactions of this
variable with the autom4te cache are quite problematic and can cause subtle
breakage, so you might want to disable the cache if you want to use
CONFIG_STATUS_DEPENDENCIES adds dependencies to the
config.status rule, whose effect is to run configure.
This variable should therefore carry any non-standard source that may
be read as a side effect of running configure, like version.sh
in the example above.
Speaking of version.sh scripts, we recommend against them today. We recommend that version.sh be replaced by an M4 file that is included by configure.ac:
m4_include([version.m4]) AC_INIT([name], VERSION_NUMBER) AM_INIT_AUTOMAKE ...
Here version.m4 could contain something like ‘m4_define([VERSION_NUMBER], [1.2])’. The advantage of this second form is that automake will take care of the dependencies when defining the rebuild rule, and will also distribute the file automatically.