getOpt' checks "non-option options"

When given RequireOrder the getOpt' function should not
parse options
following a non-option.  But currently (as of version
6.4.1 of ghc) it
does.  E.g. when parsing with RequireOrder and if
invalid-opt3 is not a
recognized option then the following produces an error:

  progname --valid-opt1 --valid-opt2 non-opt --invalid-opt3

However, anything after non-opt should not be parsed. 
The problem can be
fixed as follows:

164c164
<          procNextOpt (NonOpt x)   RequireOrder      =
([],x:rest,us,[])
---
>          procNextOpt (NonOpt x)   RequireOrder      =
([],x:rest,[],[])

Best
Sebastian