On 2012-03-18 18:24 +0100, Hans-Peter Nilsson wrote: > Hi. I don't see a way to turn on option-checking after it being > disabled-by-default due to AC_CONFIG_SUBDIRS. I had expected to > find either an option to AC_DISABLE_OPTION_CHECKING, > e.g. something like AC_DISABLE_OPTION_CHECKING([false]), or > alternatively and more intuitively than two negatives IMHO; > something like AC_OPTION_CHECKING(whichever). A quick grep for > OPTION_CHECKING in the autoconf git repo didn't find me any new > construct to achieve this. > > So, can I have a way to turn *on* option-checking by default > from configure.ac and regardless of AC_CONFIG_SUBDIRS, please? > > Why this odd request? In RAPP, > <http://savannah.nongnu.org/projects/rapp> (feel very welcome to > have a look at its configure.ac), there's the hopefully > self-explanatory: > > # The directory test/installtest isn't configured until after > # installation, but to make autoreconf update this directory we > # have to mention it here > if false; then > AC_CONFIG_SUBDIRS([test/installtest]) > fi It is actually the call to AC_CONFIG_SUBDIRS which disables option checking. Since you're only doing this to make autoreconf recurse into the subdirectory, and don't actually care about the expansion of AC_CONFIG_SUBDIRS, you can fool autoreconf into thinking you called AC_CONFIG_SUBDIRS without actually doing so. For example: dnl Fool autoreconf into thinking we called AC_CONFIG_SUBDIRS here by dnl temporily suppressing its definition. m4_pushdef([AC_CONFIG_SUBDIRS], []) AC_CONFIG_SUBDIRS([test/installtest]) m4_popdef([AC_CONFIG_SUBDIRS]) This is (ab)using internal details of autoreconf, thus it might not be guaranteed to work in the future. Cheers, -- Nick Bowler, Elliptic Technologies (http://www.elliptictech.com/) _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx https://lists.gnu.org/mailman/listinfo/autoconf
