Alexander Markov

Bisected this change in behavior to https://github.com/dart-lang/sdk/commit/efdffab8b77f5ca21ee08e2b7bb8b05a312a1317. /cc @mkustermann @lrhn Before that change, execution of `async*` closure continued up to `await completer.future` and the exception from `event.completeError(Exception())` was thrown and...

Happened once again: ``` ================== WARNING: ThreadSanitizer: data race (pid=7841) Read of size 8 at 0x563395138f98 by thread T18: #0 icu_68::umtx_initImplPreInit(icu_68::UInitOnce&) ??:? (dart+0x29043bc) #1 (anonymous namespace)::getInclusionsForSource(UPropertySource, UErrorCode&) characterproperties.cpp:? (dart+0x2806b09) #2...

... and again: ``` WARNING: ThreadSanitizer: data race (pid=2599) Atomic read of size 1 at 0x56269e311478 by thread T6: #0 pthread_mutex_lock ??:? (dart+0x1fcadfa) #1 std::__2::mutex::lock() mutex.cpp:? (dart+0x2c55c15) #2 u_getBinaryPropertySet_68 ??:?...

Bisected to 2ead86ab9dcbfe9217af01670c7d93ede73381c9. /cc @brianquinlan

We have some logic for creating and caching `PatchClass` objects in `KernelLoader::ClassForScriptAt`. `PatchClass` object is used instead of `Class` when member has a script which is different from the script...

In order to support dynamic invocations of record field getters AOT now tracks all possible shapes of record objects in a program. Record shapes which were not present during compilation...

@aam Consider trying out simpler and faster hash functions, such as Jenkins hash. Multiplication is quite slow compared to shift, addition and bitwise operations. Maybe @mraleph @mkustermann have better ideas.

There are still a few TODOs referencing this issue in the VM source code. So we can leave this issue open until those TODOs are addressed or cleaned up.

`service_2/async_generator_breakpoint_test/dds_1` turned flaky -> Timeout on `dartk-checked-linux-release-x64` configuration: https://dart-ci.appspot.com/log/vm-kernel-checked-linux-release-x64/dartk-checked-linux-release-x64/14841/service_2/async_generator_breakpoint_test/dds_1

Same happened on dartk-linux-release-arm64. Log: https://dart-ci.appspot.com/log/cross-vm-linux-release-arm64/dartk-linux-release-arm64/9827/service_2/evaluate_activation_test/scope/dds