27.6.2 Other Variables

There are other variables in Automake that follow similar principles to allow user options. For instance, Texinfo rules (see section Texinfo) use MAKEINFOFLAGS and AM_MAKEINFOFLAGS. Similarly, DejaGnu tests (see section Support for test suites) use RUNTESTDEFAULTFLAGS and AM_RUNTESTDEFAULTFLAGS. The tags and ctags rules (see section Interfacing to etags) use ETAGSFLAGS, AM_ETAGSFLAGS, CTAGSFLAGS, and AM_CTAGSFLAGS. Java rules (see section Java) use JAVACFLAGS and AM_JAVACFLAGS. None of these rules do support per-target flags (yet).

To some extent, even AM_MAKEFLAGS (see section Recursing subdirectories) obeys this naming scheme. The slight difference is that MAKEFLAGS is passed to sub-makes implicitly by make itself.

However you should not think that all variables ending with FLAGS follow this convention. For instance, DISTCHECK_CONFIGURE_FLAGS (see section What Goes in a Distribution), ACLOCAL_AMFLAGS (see Rebuilding Makefiles and Handling Local Macros), are two variables that are only useful to the maintainer and have no user counterpart.

ARFLAGS (see section Building a library) is usually defined by Automake and has neither AM_ nor per-target cousin.

Finally you should not think either that the existence of a per-target variable implies that of an AM_ variable or that of a user variable. For instance, the mumble_LDADD per-target variable overrides the global LDADD variable (which is not a user variable), and mumble_LIBADD exists only as a per-target variable. See section Program and Library Variables.