glibc/sysdeps/unix/sysv/sysv4/solaris2/configure.in

sinclude(./aclocal.m4)dnl Autoconf lossage
GLIBC_PROVIDES dnl See aclocal.m4 in the top level source directory.
# Local configure fragment for sysdeps/unix/sysv/sysv4/solaris2

# Concensus on stdio is that it's broken.
test $stdio = default && stdio=libio

# Crypt is your friend.
case $add_ons in
  *crypt*)
    message=
    ;;
  *)
    message="\
*** WARNING:
*** Are you sure you do not want to use the \`crypt' add-on?"
    ;;
esac

if test "$message"; then
  if test $enable_sanity = yes; then
    echo "\
*** You should not compile the GNU libc without the \`crypt' add-on.
*** Not using them risks to be incompatible with the libraries of
*** other systems.  Consider getting the add-on and restart the
*** configuration.
*** If you reall mean to avoid this add-on run configure again, now
*** using the extra parameter \`--disable-sanity-checks'."
    exit 1
  else
    echo "$message"
  fi
fi