Hello, On Mon, Nov 27, 2006 at 07:49:14AM -0800, Bruce Korb wrote: > On 11/26/06, Ralf Wildenhues <Ralf.Wildenhues@xxxxxx> wrote: > >* Bruce Korb wrote on Mon, Nov 27, 2006 at 02:40:07AM CET: > >> # ---------------------------------------------------------------------- > >> # check for various programs used during the build. > >> # On OS/X, "wchar.h" needs "runetype.h" to work properly. > >> # ---------------------------------------------------------------------- ... > >AC_CHECK_HEADERS([runetype.h wchar.h], [], [],[ > >AC_INCLUDES_DEFAULT > >#if HAVE_RUNETYPE_H > ># include <runetype.h> > >#endif > >]) actually, things might be clearer if we refrain from optimization: # First, check for runetype.h (and define HAVE_RUNETYPE_H iff it is # found): AC_CHECK_HEADERS([runetype.h]) # Then check for wchar.h. Amend the standard prologue to include # runetype.h (if it has been found) before wchar.h. (This is needed # on OS X.) AC_CHECK_HEADERS([wchar.h], [], [], [ AC_INCLUDES_DEFAULT #ifdef HAVE_RUNETYPE_H # include <runetype.h> #endif ]) [A side note: I changed #if -> #ifdef, this is the preferred variant in recent versions of Autoconf.] Then the manual could say that an optimization is possible, which merges the two huge code chunks which are expanded from AC_CHECK_HEADERS: # First, check for runetype.h (and define HAVE_RUNETYPE_H iff it is # found). # In the second iteration, check for wchar.h. Amend the standard # prologue to include runetype.h (if it has been found) before # wchar.h. (This is needed on OS X.) AC_CHECK_HEADERS([runetype.h wchar.h], [], [], [ AC_INCLUDES_DEFAULT #ifdef HAVE_RUNETYPE_H # include <runetype.h> #endif ]) > BTW, is there an abbreviated way of saying, ``add all the headers we've > checked on to the list of "AC_INCLUDES_DEFAULT"?'' Various header files can conflict, when included together. So I believe this practice would lead to serious problems. It is better to identify the cases when a header requires another but does not include it, and handle them. Have a nice day, Stepan Kasal _______________________________________________ Autoconf mailing list Autoconf@xxxxxxx http://lists.gnu.org/mailman/listinfo/autoconf
