* sprintf.c (rb_f_sprintf): preceding ".." for negative
  hexadecimal numbers should not appear if prec (e.g. %.4) is
  specified.

* compar.c (cmp_eq,cmp_gt,cmp_ge,cmp_lt,cmp_le): "<=>" might
  return nil.  check using rb_cmpint().

* error.c (init_syserr): remove sys_nerr dependency.

* regex.c (re_match): avoid dereferencing if size == 0.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_6@3112 b2dd03c8-39d4-4d8f-98ff-823fe69b080e