> - macros defined with AC_DEFUN_IDEMPOTENT are *known* to be expandable > any number of times, hence they may be both invoked and required, > > - macros defined with AC_DEFUN_ONCE are *known* to be expandable only > once, hence the recommendation for them is to AC_REQUIRE them,
Do we have any of these? I'd just change AC_DEFUN_ONCE to the meaning you suggest for AC_DEFUN_IDEMPOTENT, with this further change to its semantics: if an AC_DEFUN_ONCE is invoked from the toplevel, never warn; if it is invoked from a macro without AC_REQUIRE, always warn. For 2.65 we can start using AC_DEFUN_ONCE more liberally in autoconf itself Paolo
