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llvm / llvm-project / 7b346357db30d531245104c1c0aa8940a1f41b9a
commit7b346357db30d531245104c1c0aa8940a1f41b9a[log] [tgz]
authorFangrui Song <i@maskray.me>Tue Jun 04 09:14:54 2024 -0700
committerGitHub <noreply@github.com>Tue Jun 04 09:14:54 2024 -0700
treec0a59e54ae51f5e6d339e4df004ece4dff5d6063
parent6ac5047aa6bf12644e38afb188bd8d821a181ba5 [diff]
[ELF] Orphan placement: prefer the last similar section when its rank <= orphan's rank

`findOrphanPos` finds the most similar output section (that has input
sections). In the event of proximity ties, we select the first section.

However, when an orphan section's rank is equal to or larger than the
most similar sections's, it makes sense to prioritize the last similar
section. This new behavior matches GNU ld better.

```
// orphan placement for .bss (SHF_ALLOC|SHF_WRITE, SHT_NOBITS)

WA SHT_PROGBITS
(old behavior) <= here
A
WA SHT_PROGBITS
AX
WA (.data)
(new behavior) <= here
```

When the orphan section's rank is less, the current behavior
prioritizing the first section still makes sense.
```
// orphan with a smaller rank, e.g. .rodata

<= here
WA
AX
WA
```

Close #92987

Pull Request: https://github.com/llvm/llvm-project/pull/94099
4 files changed
tree: c0a59e54ae51f5e6d339e4df004ece4dff5d6063
  1. .ci/
  2. .github/
  3. bolt/
  4. clang/
  5. clang-tools-extra/
  6. cmake/
  7. compiler-rt/
  8. cross-project-tests/
  9. flang/
  10. libc/
  11. libclc/
  12. libcxx/
  13. libcxxabi/
  14. libunwind/
  15. lld/
  16. lldb/
  17. llvm/
  18. llvm-libgcc/
  19. mlir/
  20. offload/
  21. openmp/
  22. polly/
  23. pstl/
  24. runtimes/
  25. third-party/
  26. utils/
  27. .clang-format
  28. .clang-tidy
  29. .git-blame-ignore-revs
  30. .gitattributes
  31. .gitignore
  32. .mailmap
  33. CODE_OF_CONDUCT.md
  34. CONTRIBUTING.md
  35. LICENSE.TXT
  36. pyproject.toml
  37. README.md
  38. SECURITY.md
README.md

The LLVM Compiler Infrastructure

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Welcome to the LLVM project!

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