ASAN leaves a pointer to the fake frame on the stack; we can use the
__asan_addr_is_in_fake_stack API to work out the extent of the fake
stack and thus mark any VALUEs contained therein.

[Bug #20001]

This reverts commit d10bc3a2b8300cffc383e10c3730871e851be24c.

ASAN leaves a pointer to the fake frame on the stack; we can use the
__asan_addr_is_in_fake_stack API to work out the extent of the fake
stack and thus mark any VALUEs contained therein.

[Bug #20001]

Too complex classes use a hash table to store ivs, and should always pin
their IVs.  We shouldn't touch those classes in compaction.

This commit dumps the `mid` of the imemo callinfo when calling
`ObjectSpace.dump_all`.

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.

* Add deprecations for public struct rb_io members.

This reverts commit 10621f7cb9a0c70e568f89cce47a02e878af6778.

This was reverted because the gc integrity build started failing. We
have figured out a fix so I'm reopening the PR.

Original commit message:

Fix cvar caching when class is cloned

The class variable cache that was added in
ruby#4544 changed the behavior of class
variables on cloned classes. As reported when a class is cloned AND a
class variable was set, and the class variable was read from the
original class, reading a class variable from the cloned class would
return the value from the original class.

This was happening because the IC (inline cache) is stored on the ISEQ
which is shared between the original and cloned class, therefore they
share the cache too.

To fix this we are now storing the `cref` in the cache so that we can
check if it's equal to the current `cref`. If it's different we don't
want to read from the cache. If it's the same we do. Cloned classes
don't share the same cref with their original class.

This will need to be backported to 3.1 in addition to 3.2 since the bug
exists in both versions.

We also added a marking function which was missing.

Fixes [Bug #19379]

Co-authored-by: Aaron Patterson <tenderlove@ruby-lang.org>

This reverts commit 77d1b082470790c17c24a2f406b4fec5d522636b.