Hi, Currently, automake doesn't set any of the various *CLEANFILES variables. Since the "+=" syntax is not portable when the variables are not initialized (and causes an automake warning), this leaves no option for Makefile.am snippets from various tools other than using the *clean-local targets to do their cleanups. The problem with this is that it's imperative as opposed to declarative.
I've been maintaining a pieces of Makefile.am snippet called git.mk: http://git.gnome.org/browse/pango/tree/git.mk What it does is to generate .gitignore files based on what "make maintainer-clean" removes. However, because of the problem stated above, I cannot simply aggregate the various *CLEANFILES variables and also have to add support for individual tools (autoconf, automake, libtool, gtk-doc, gnome-doc-utils, mallard, intltool, and gsettings so far). If instead automake was changed to always pre-initialize *CLEANFILES variables, all snippets could just append to do variables and my git.mk snippet would be more generic and much more simpler at the same time. So I want to suggest that automake be changed to initialized *CLEANFILES if the Makefile.am doesn't initialize them explicitly. In another note, if that change is made and my git.mk simplified to not have tool-specific logic in it, it would be a great addition to automake itself. Cheers, behdad
