Configure options to disable some features, which are checked using
AC_ARG_ENABLE can be invoked with --enable-<option> as well.
The current configure script always generates a #define for such options
even though the --enable-<option> case should not generate a #define.
Fix this by properly checking if the feature should be enabled, in which
case no #define is being generated.
Signed-off-by: Stefan Hauser <stefan@shauser.net>
if the system doesn't support getpass, we still default on the options
that require it which causes a build failure. instead, only default
enable these when getpass is available.
Instead of declaring an "unused-variable" or "unused-but-set-variable"
structure.
This avoid unexpected broken configurations when using something like:
$ ./configure CFLAGS="-Wall -Wextra -Werror"
It causes AC_COMPILE_IFELSE to fail and thus leading to a mismatch
configuration (because the CFLAGS are passed to the macro).
