If find is set to search for file matching a regular expression (-regex ’.*’),
the argument pointer arg_ptr is incremented (parser.c:1644) before it is used
(parser.c:1645) which results in a nullpointer dereference (parser.c:926). 

Examples of Correct Fixes: 
1) Increment arg_ptr *after* argv[*arg_ptr] is read.

2) Save the previous value of argv[*arg_ptr] in a temporary variable and use
this one. 

Examples of Incorrect Fixes: 
1) Do not increment arg_ptr at all (Regression because other arguments may not
be parsed at all). 

2) Add null-pointer check (Incomplete Fix because estimate pattern match is
still called with a nullpointer).
