Hi, I've solved my problem ;) I finally found that I was using
LDFLAGS="$LDFLAGS -ltotest" AC_LINK_IFELSE([ AC_LANG_PROGRAM([#include <wx/url.h>], [wxURL u(wxT("http://www.google.it"));]) ], [WXURL_PRESENCE=1], [WXURL_PRESENCE=0]) instead of LIBS="$LIBS -ltotest" AC_LINK_IFELSE([ AC_LANG_PROGRAM([#include <wx/url.h>], [wxURL u(wxT("http://www.google.it"));]) ], [WXURL_PRESENCE=1], [WXURL_PRESENCE=0]) Using LIBS instead of LDFLAGS solved the problem ! Francesco