* doc/sourcebuild.texi (Test directives): Document that arguments
include-opts and exclude-opts are now optional for dg-skip-if,
dg-xfail-if, dg-xfail-run-if, and dg-shouldfail.
* lib/target-supports-dg.exp (check-flags): Provide defaults for
include-opts and exclude-opts; skip checking the flags if arguments
are the same as the defaults.
(dg-xfail-if): Verify the number of arguments, supply defaults
for unspecified optional arguments.
(dg-skip-if, dg-xfail-run-if): Verify the number of arguments.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@157206 138bc75d-0d04-0410-961f-82ee72b054a4