Make RbConfig::CONFIG values mutable [Bug #16738]

	As `RbConfig.expand` modifies the argument and involved `CONFIG`
	values, its values should be mutable.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67872 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	Fixed duplicated warning

	As `command_rhs` is always a "value expression", `command_asgn`
	does not need the same check.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67868 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	Do not turn on keyword_init for Struct subclass if keyword hash is
	 empty

	This was accidentally turned on because there was no checking for
	Qundef.

	Also, since only a single keyword is currently supported, simplify
	the rb_get_kwargs call.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67866 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	`Regexp` in `MatchData` can be `nil`

	`String#sub` with a string pattern defers creating a `Regexp`
	until `MatchData#regexp` creates a `Regexp` from the matched
	string.  `Regexp#last_match(group_name)` accessed its content
	without creating the `Regexp` though.  [Bug #16508]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67865 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	time.c (find_time_t): fix round-to-zero bug

	`find_time_t` did not work correctly for year older than the Epoch
	because it used C's integer division (which rounds negative to zero).

	For example, `TIme.new(1933)` returned a wrong time whose year is 1922
	in Asia/Kuala_Lumpur because there is no 00:00:00 1st Jan. 1933 in the
	time zone.

	```
	$ TZ=Asia/Kuala_Lumpur ruby -e 'p Time.new(1933)'
	1932-12-31 00:00:00 +0700
	```

	This change fixes the issue by using `DIV` macro instead of `/`.
	Now `Time.new(1933)` returns a time in 1933.

	```
	$ TZ=Asia/Kuala_Lumpur ruby -e 'p Time.new(1933)'
	1933-01-01 00:20:00 +0720
	```

	[Bug #16159]

	Added a test for [Bug #16159]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67864 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	Guard static variable first

	* ext/openssl/ossl_asn1.c (Init_ossl_asn1): register the static
	  variable to grab an internal object, before creating the object.
	  otherwise the just-created object could get collected during the
	  global variable list allocation.  [Bug #16196]

	Slimed down test runtime by stressing openssl.so only [Bug #16196]


	Prefer rb_gc_register_mark_object

	* ext/openssl/ossl_asn1.c (Init_ossl_asn1): prefer
	  `rb_gc_register_mark_object`, which is better for constant
	  objects, over `rb_gc_register_address` for global/static
	  variables which can be re-assigned at runtime.  [Bug #16196]

	Skip very time consuming test [Bug #16196]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67863 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	marshal.c: check instance variable count

	* marshal.c (w_obj_each): ensure that no instance variable was
	  added while dumping other instance variables.  [Bug #15968]

	Hoisted out w_ivar_each


	marshal.c: check instance variable count

	* marshal.c (w_ivar_each): ensure that no instance variable was
	  removed while dumping other instance variables.  [Bug #15968]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67861 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

	test_ftp.rb: loosen timeout for Travis osx

	https://travis-ci.org/ruby/ruby/jobs/454798071

	git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65723 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67829 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

`FileTest.send(command, ...)` allows to call not only FileTest-related
methods but also any method that belongs to Kernel, Object, etc.
patched by <mame@ruby-lang.org>


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67814 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

WEBrick: prevent response splitting and header injection

This is a follow up to d9d4a28.
The commit prevented CRLR, but did not address an isolated CR or an
isolated LF.

Co-Authored-By: NARUSE, Yui <naruse@airemix.jp>


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_5@67813 b2dd03c8-39d4-4d8f-98ff-823fe69b080e