Just check if iteration level is non-zero

The level in ivar is no longer needed to check if iterating, only used
for increment/decrement.

Old YJIT backend (x86-64 only), for benchmarking purposes.

Merge 'gh/master' into rust-yjit

teenyup

Revert "Do not include external library sources into packages"

This reverts commit a042043.

(cherry picked from commit 8325094)

 Fix integer overflow

    Make use of the check in rb_alloc_tmp_buffer2.

    https://hackerone.com/reports/1328463

    When parsing cookies, only decode the values

    Bump version

    Co-authored-by: Nobuyoshi Nakada <[email protected]>
    Co-authored-by: Yusuke Endoh <[email protected]>

merge some parts of CGI 0.1.1

	Fix integer overflow

	Make use of the check in rb_alloc_tmp_buffer2.

	When parsing cookies, only decode the values

	Bump version

add tag v2_6_9

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/tags/v2_6_9@67954 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

Needs `$` in `make` command line to be escaped