Hello Vincent, * Vincent Torri wrote on Tue, Dec 26, 2006 at 06:39:27PM CET: [...] > I've installed STLport 5.1 in /usr/local. So, the first check (in /usr) > returns a warning, and then STLport is searched in /usr/local. The result > of the configure script is the following: > > checking stl/config/user_config.h usability... no > checking stl/config/user_config.h presence... no > checking for stl/config/user_config.h... no > configure: WARNING: STLport headers not in /usr/include/stlport > checking for stl/config/user_config.h... (cached) no > configure: WARNING: STLport headers not in /usr/local/include/stlport > configure: error: "STLport is needed !" > Can someone explain what the problem is, and then what kind of solution > there is to such problem ? Autoconf caching assumes that AC_CHECK_HEADERS checks do not depend on other state. (This is at least somewhat reasonable: all other header checks could change if you change CPPFLAGS after them.) You have two ways to fix your macro: 1) Put a unset ac_cv_header_std_config_user_config_h before your test. 2) Roll your own manual test (using AC_COMPILE_IFELSE, AC_PREPROC_IFELSE, AC_LANG_PROGRAM etc.) that uses no caching or a manual form of unambiguous caching. The first has the advantage of being simple, but the disadvantages of being more expensive for rechecks (e.g., `./config.status --recheck'), and a wee bit less portable, see <http://www.gnu.org/software/autoconf/manual/html_node/Limitations-of-Builtins.html#index-g_t_0040command_007bunset_007d-1259>. But that's probably not a problem for you in practice. In any case your users will see an error if unset does not work. The second solution is a bit more work. ;-) I think Eric covered the rest of your mail. Cheers, Ralf _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf
