error[E0080]: evaluation of constant value failed
  --> tests/ui/guid_sep.rs:12:14
   |
12 |     let _g = guid!("01234567089ab-cdef-0123-456789abcdef");
   |              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ the evaluated program panicked at 'GUID string is missing one or more separators (`-`)', $DIR/tests/ui/guid_sep.rs:12:14
   |
   = note: this error originates in the macro `guid` (in Nightly builds, run with -Z macro-backtrace for more info)