[LifetimeSafety] Detect dangling fields (#177363)

Detect dangling field references when stack memory escapes to class
fields. This change extends lifetime safety analysis to detect a common
class of temporal memory safety bugs where local variables or parameters
are stored in class fields but outlive their scope.

- Added a new `FieldEscapeFact` class to represent when an origin
escapes via assignment to a field
- Refactored `OriginEscapesFact` into a base class with specialized
subclasses for different escape scenarios
- Added detection for stack memory escaping to fields in constructors
and member functions
- Implemented new diagnostic for dangling field references with
appropriate warning messages

Importantly,
- Added `AddParameterDtors` option to CFG to add parameter dtors and
lifetime ends behind an option. In principle, parameters ctors and dtors
do not belong in the function context but in the caller context. This
becomes incorrect to include in function's CFG when we have inlined CFGs
like some analyses in the analyzer (produces double dtors for
arguments). Therefore this provides a way to opt-in to know about
destructed params on function exits.
21 files changed
tree: 40d7385328a1be464282eaedee2673e19839df2f
  1. .ci/
  2. .github/
  3. bolt/
  4. clang/
  5. clang-tools-extra/
  6. cmake/
  7. compiler-rt/
  8. cross-project-tests/
  9. flang/
  10. flang-rt/
  11. libc/
  12. libclc/
  13. libcxx/
  14. libcxxabi/
  15. libsycl/
  16. libunwind/
  17. lld/
  18. lldb/
  19. llvm/
  20. llvm-libgcc/
  21. mlir/
  22. offload/
  23. openmp/
  24. orc-rt/
  25. polly/
  26. runtimes/
  27. third-party/
  28. utils/
  29. .clang-format
  30. .clang-format-ignore
  31. .clang-tidy
  32. .git-blame-ignore-revs
  33. .gitattributes
  34. .gitignore
  35. .mailmap
  36. CODE_OF_CONDUCT.md
  37. CONTRIBUTING.md
  38. LICENSE.TXT
  39. pyproject.toml
  40. README.md
  41. SECURITY.md
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