Name already in use

It's a bad idea to overwrite the flags as the garbage collector may have
set other flags.

  It's needless with racc-1.7.1

Separate the directly from the customized test-unit, since it may not
work with bundled gems.

of prefix
(ruby/irb#603)

ruby/irb@359cb28def

completion candidates including newline characters
(ruby/irb#539)

ruby/irb@aaf0c46645

rubygems/rubygems@e916ccb2d9

ruby/uri@8e38592241

ruby/uri@3dfa19e920

This reverts commit 888ba29.

It caused a CI failure
http://ci.rvm.jp/results/trunk-yjit@ruby-sp2-docker/4598881
and I'm investigating it.

ruby/psych@715f3bfad0

Since no type information is available for variadic arguments, 0 is
passed as `int` without promoting to pointer.  On platforms where
`sizeof(int) < sizeof(void*)`, the terminator argument may be read
together with an adjoining word, and may not be found.

Please consider using misc/expand_tabs.rb as a pre-commit hook.

Introduce Universal Parser mode for the parser.
This commit includes these changes:

* Introduce `UNIVERSAL_PARSER` macro. All of CRuby related functions
  are passed via `struct rb_parser_config_struct` when this macro is enabled.
* Add CI task with 'cppflags=-DUNIVERSAL_PARSER' for ubuntu.

Bumps [actions/checkout](https://github.com/actions/checkout) from 3.5.2 to 3.5.3.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@8e5e7e5...c85c95e)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

ruby/psych@ba6fc48591

Bumps [github/codeql-action](https://github.com/github/codeql-action) from 2.3.5 to 2.13.4.
- [Release notes](https://github.com/github/codeql-action/releases)
- [Changelog](https://github.com/github/codeql-action/blob/main/CHANGELOG.md)
- [Commits](github/codeql-action@0225834...cdcdbb5)

---
updated-dependencies:
- dependency-name: github/codeql-action
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

ruby/psych@33024ce2b0