pub unsafe extern fn dgttrs_(trans: *const c_char,
n: *const lapack_int,
nrhs: *const lapack_int,
dl: *const c_double,
d: *const c_double,
du: *const c_double,
du2: *const c_double,
ipiv: *const lapack_int,
b: *mut c_double,
ldb: *const lapack_int,
info: *mut lapack_int)