[cpyrt] Use GetActualClass in cast_actual

[aaronj0]

cast_actual kept the static class, so comparing two proxies of the same object through different base subobjects compared unequal addresses. Reachable when a proxy is not downcast on creation, e.g. for a pinned type. Also drops a stray '&' from the ostream operand name used for the operator<< lookup, and fixes two comment typos.

From the ROOT migration.

[guitargeek]

LGTM! Thanks for porting this over.

[github-actions]

CppJIT CI has detected a new failure on workflow Test running on main while building 83b0fca at job "ubuntu-24.04/llvm21/py3.12/c++20 / run".

Full details are available at: https://github.com/compiler-research/cppjit/actions/runs/34196434718
Here is the relevant piece of the build log for the reference

Step "Build and test" failure:
  Python3_ROOT_DIR: /opt/hostedtoolcache/Python/3.12.14/x64
  LD_LIBRARY_PATH: /opt/hostedtoolcache/Python/3.12.14/x64/lib
  LLVM_DIR: /home/runner/work/cppjit/cppjit/install/lib/cmake/llvm
  Clang_DIR: /home/runner/work/cppjit/cppjit/install/lib/cmake/clang
##[endgroup]
(node:6082) [DEP0040] DeprecationWarning: The `punycode` module is deprecated. Please use a userland alternative instead.
(Use `node --trace-deprecation ...` to show where the warning was created)
With the provided path, there will be 1 file uploaded
Artifact name is valid!
Root directory input is valid!
Beginning upload of artifact content to blob storage
(node:6082) [DEP0169] DeprecationWarning: `url.parse()` behavior is not standardized and prone to errors that have security implications. Use the WHATWG URL API instead. CVEs are not issued for `url.parse()` vulnerabilities.
Uploaded bytes 207
Finished uploading artifact content to blob storage!
SHA256 digest of uploaded artifact zip is 8a30bfc831ac712f868fab297494d030f1c83254c3d42f589f6c995b585bcfac
Finalizing artifact upload
Artifact result-ubuntu-24.04-llvm21-py3.12-cxx20.zip successfully finalized. Artifact ID 10044141501
Artifact result-ubuntu-24.04-llvm21-py3.12-cxx20 has been successfully uploaded! Final size is 207 bytes. Artifact ID is 10044141501
Artifact download URL: https://github.com/compiler-research/cppjit/actions/runs/34196434718/artifacts/10044141501
Post job cleanup.
Node 20 is being deprecated. This workflow is running with Node 24 by default. If you need to temporarily use Node 20, you can set the ACTIONS_ALLOW_USE_UNSECURE_NODE_VERSION=true environment variable. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/
Post job cleanup.
[command]/usr/bin/git version
git version 2.55.0
Temporarily overriding HOME='/home/runner/work/_temp/60ad09f7-63d1-462c-93c8-a2888e89dbf3' before making global git config changes
Adding repository directory to the temporary git global config as a safe directory
[command]/usr/bin/git config --global --add safe.directory /home/runner/work/cppjit/cppjit
[command]/usr/bin/git config --local --name-only --get-regexp core\.sshCommand
[command]/usr/bin/git submodule foreach --recursive sh -c "git config --local --name-only --get-regexp 'core\.sshCommand' && git config --local --unset-all 'core.sshCommand' || :"
[command]/usr/bin/git config --local --name-only --get-regexp http\.https\:\/\/github\.com\/\.extraheader
http.https://github.com/.extraheader
[command]/usr/bin/git config --local --unset-all http.https://github.com/.extraheader
[command]/usr/bin/git submodule foreach --recursive sh -c "git config --local --name-only --get-regexp 'http\.https\:\/\/github\.com\/\.extraheader' && git config --local --unset-all 'http.https://github.com/.extraheader' || :"
[command]/usr/bin/git config --local --name-only --get-regexp ^includeIf\.gitdir:
[command]/usr/bin/git submodule foreach --recursive git config --local --show-origin --name-only --get-regexp remote.origin.url
Evaluate and set job outputs
Set output 'summary'
Cleaning up orphan processes
##[warning]Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4, actions/setup-python@v5, actions/upload-artifact@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/