docs: autom4te cache can break CONFIGURE_DEPENDENCIES

In fact, the new test 'remake-configure-dependencies.sh' only
works because it disables the autom4te cache :-(  That is more
of an AUtotools design issue than an Automake bug, so better
just document it ...

* doc/automake.texi (Rebuilding): ... here.

Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>

diff --git a/doc/automake.texi b/doc/automake.texi
index 47a8e3a..b4dad5c 100644 (file)
--- a/doc/automake.texi
+++ b/doc/automake.texi
@@ -9911,7 +9911,11 @@ Beware not to mistake @code{CONFIGURE_DEPENDENCIES} for
 variable should be seldom used, because @command{automake} already tracks
 @code{m4_include}d files.  However it can be useful when playing
 tricky games with @code{m4_esyscmd} or similar non-recommendable
-macros with side effects.
+macros with side effects.  Be also aware that interactions of this
+variable with the @ref{Autom4te Cache, , autom4te cache, autoconf,
+The Autoconf Manual} are quite problematic and can cause subtle
+breakage, so you might want to disable the cache if you want to use
+@code{CONFIGURE_DEPENDENCIES}.
 
 @code{CONFIG_STATUS_DEPENDENCIES} adds dependencies to the
 @file{config.status} rule, whose effect is to run @file{configure}.