At the top of a loop, loop-assigned variables need to be marked as not
definitely unassigned, otherwise we will give incorrect results for
code like this:
```dart
f() {
late int x;
bool firstIteration = true;
while (true) {
if(firstIteration) {
x = 0;
firstIteration = false;
} else {
print(x); // BOGUS ERROR: x definitely unassigned
}
}
}
```
Previously, we were handling this by calling `joinUnassigned` at the
bottom of `removePromotedAll`, but it's simpler to just mark these
variables as not-unassigned while discarding promotions. This change
will make the implementation more closely match spec changes I'll be
making shortly.
Change-Id: If50e28d20a75730aa5187a62ae5cac8690b0dfaf
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/152861
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Commit-Queue: Paul Berry <paulberry@google.com>
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.
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Dart Web: For programs targeting the web, Dart Web includes both a development time compiler (dartdevc) and a production time compiler (dart2js).
License & patents
Dart is free and open source.
See LICENSE and PATENT_GRANT.
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