[cfe] Ensure that shorting is stopped before expression usage

The creation of the shorting stop expression was done lazily
in NullAwareExpressionInferenceResult.expression. Since the shorting
calls flow analysis to stop null promotion doing this out of order
let to inconsistent flow analysis state.

This CL introduces an `inferNullAwareExpression` the allows to
caller to continue the shorting (if in an opt-in library). The
inferExpression method, used everywhere else, stops any shorting
currently in progress.

Closes #43275

Change-Id: I448163e29bdb0de8e493e5c62aa0474d0c9a593f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/173729
Reviewed-by: Dmitry Stefantsov <dmitryas@google.com>
Commit-Queue: Johnni Winther <johnniwinther@google.com>
9 files changed
tree: b6f97f358918e568b670a0a2983811fac2277d79
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. client/
  6. docs/
  7. pkg/
  8. runtime/
  9. samples/
  10. samples-dev/
  11. samples_2/
  12. sdk/
  13. tests/
  14. third_party/
  15. tools/
  16. utils/
  17. .clang-format
  18. .gitattributes
  19. .gitconfig
  20. .gitignore
  21. .gn
  22. .mailmap
  23. .packages
  24. .style.yapf
  25. .vpython
  26. AUTHORS
  27. BUILD.gn
  28. CHANGELOG.md
  29. codereview.settings
  30. CONTRIBUTING.md
  31. DEPS
  32. LICENSE
  33. PATENT_GRANT
  34. PRESUBMIT.py
  35. README.dart-sdk
  36. README.md
  37. sdk_args.gni
  38. WATCHLISTS
README.md

Dart

A client-optimized language for fast apps on any platform

Dart is:

  • Optimized for UI: Develop with a programming language specialized around the needs of user interface creation

  • Productive: Make changes iteratively: use hot reload to see the result instantly in your running app

  • Fast on all platforms: Compile to ARM & x64 machine code for mobile, desktop, and backend. Or compile to JavaScript for the web

Dart's flexible compiler technology lets you run Dart code in different ways, depending on your target platform and goals:

  • Dart Native: For programs targeting devices (mobile, desktop, server, and more), Dart Native includes both a Dart VM with JIT (just-in-time) compilation and an AOT (ahead-of-time) compiler for producing machine code.

  • Dart Web: For programs targeting the web, Dart Web includes both a development time compiler (dartdevc) and a production time compiler (dart2js).

Dart platforms illustration

License & patents

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See LICENSE and PATENT_GRANT.

Using Dart

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There are more documents on our wiki.

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