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commit4bb89c4a93e5b09694c053f11c92a6ff07e66c44[log] [tgz]
authorRust timing bot <rust-timer@users.noreply.github.com>Thu Aug 28 08:14:26 2025 +0200
committerGitHub <noreply@github.com>Thu Aug 28 08:14:26 2025 +0200
treec6f93d924a3746372bbf11f1f117d39a433dd4af
parentd36f964125163c2e698de5559efefb8217b8b7f0 [diff]
parent5f39612e7af612f41cf2e78c254e06ad7e4c32e0 [diff]
Unrolled build for #145382
Rollup merge of #145382 - winstonallo:reg-struct-return-asm-test, r=tgross35

Add assembly test for `-Zreg-struct-return` option

r? `@tgross35`

As discussed in rust-lang/rust#145309 with `@tgross35` and `@ojeda,` I added assembly tests for the `-Zreg-struct-return` option verifying that it changes the ABI from hidden pointer to register-return on x86_32.

The test covers:
- Direct struct construction, showing register return vs hidden pointer
- External function calls returning structs, showing ABI mismatch handling

Different memory layouts affect ABI mismatch handling, but register returns use the same register allocation regardless of struct field layout (apart from the fact that they use smaller registers for smaller structs, of course).

[Here](https://godbolt.org/z/dcW6rnMG3) is a compiler explorer with 2 examples. Let me know if there is anything more I could add. Since register returns only happen for structs up to the size of 2 registers, I figured testing the pivot value (8 bytes) would be most critical.
tree: c6f93d924a3746372bbf11f1f117d39a433dd4af
  1. .github/
  2. compiler/
  3. library/
  4. LICENSES/
  5. src/
  6. tests/
  7. .clang-format
  8. .editorconfig
  9. .git-blame-ignore-revs
  10. .gitattributes
  11. .gitignore
  12. .gitmodules
  13. .ignore
  14. .mailmap
  15. bootstrap.example.toml
  16. Cargo.lock
  17. Cargo.toml
  18. CODE_OF_CONDUCT.md
  19. configure
  20. CONTRIBUTING.md
  21. COPYRIGHT
  22. INSTALL.md
  23. LICENSE-APACHE
  24. license-metadata.json
  25. LICENSE-MIT
  26. package-lock.json
  27. package.json
  28. README.md
  29. RELEASES.md
  30. REUSE.toml
  31. rust-bors.toml
  32. rustfmt.toml
  33. triagebot.toml
  34. typos.toml
  35. x
  36. x.ps1
  37. x.py
README.md

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