AC_SUBST([guix_system])
])
+dnl GUIX_ASSERT_SUPPORTED_SYSTEM
+dnl
+dnl Assert that this is a system to which the distro is ported.
+AC_DEFUN([GUIX_ASSERT_SUPPORTED_SYSTEM], [
+ AC_REQUIRE([GUIX_SYSTEM_TYPE])
+
+ AC_ARG_WITH([courage], [AC_HELP_STRING([--with-courage],
+ [Assert that even if this platform is unsupported, you will be
+courageous and port the GNU System distribution to it (see
+"GNU Distribution" in the manual.)])],
+ [guix_courageous="$withval"],
+ [guix_courageous="no"])
+
+ # Currently only Linux-based systems are supported, and only on some
+ # platforms.
+ case "$guix_system" in
+ x86_64-linux|i686-linux)
+ ;;
+ *)
+ if test "x$guix_courageous" = "xyes"; then
+ AC_MSG_WARN([building Guix on `$guix_system', which is not supported])
+ else
+ AC_MSG_ERROR([`$guix_system' is not a supported platform.
+See "GNU Distribution" in the manual, or try `--with-courage'.])
+ fi
+ ;;
+ esac
+])
+
dnl GUIX_ASSERT_GUILE_FEATURES FEATURES
dnl
dnl Assert that FEATURES are provided by $GUILE.