AC_HELP_STRING([--with-BLASname=NAME], [use NAME as the name of the BLAS library (without leading "lib" prefix and trailing suffix). Default: "blas"]),
[case "$withval" in
yes) AC_MSG_ERROR("option \"--with-BLASname\" requires an argument")
;;
no) AC_MSG_ERROR("option \"--with-BLASname\" requires an argument")
AC_HELP_STRING([--with-GLname=NAME], [use NAME as the name of the OpenGL (tm) library (without leading "lib" prefix and trailing suffix). Default: "GL"]),
[case "$withval" in
yes) AC_MSG_ERROR("option \"--with-GLname\" requires an argument")
;;
no) AC_MSG_ERROR("option \"--with-GLname\" requires an argument")