Failures on [pkg/vm] Handle switch statements in unreachable code eliminator

[dcharkes]

There are new test failures on [tests][web-fixit] Fix date_time_extremes_test....Reland "[pkg/vm] Handle switch statements in unreachable code eliminator.".

The tests

language/nnbd/boolean_conversion/boolean_conversion_weak_test RuntimeError (expected Pass)

are failing on configurations

dartkp-weak-asserts-linux-release-x64

Log: https://dart-ci.appspot.com/log/vm-kernel-precomp-linux-release-x64/dartkp-weak-asserts-linux-release-x64/15831/language/nnbd/boolean_conversion/boolean_conversion_weak_test

exit code:
255

stderr:
Unhandled exception:
Expect.throws(AssertionError) fails: Did not throw
#0      Expect._fail (package:expect/expect.dart:721)
#1      Expect.throws (package:expect/expect.dart:629)
#2      Expect.throwsAssertionError (package:expect/expect.dart:638)
#3      check (file:///b/s/w/ir/tests/language/nnbd/boolean_conversion/boolean_conversion_lib1.dart:27)
#4      main (file:///b/s/w/ir/tests/language/nnbd/boolean_conversion/boolean_conversion_weak_test.dart:18)
#5      _delayEntrypointInvocation.<anonymous closure> (dart:isolate-patch/isolate_patch.dart:297)
#6      _RawReceivePort._handleMessage (dart:isolate-patch/isolate_patch.dart:184)

--- Re-run this test:
python3 tools/test.py -n dartkp-weak-asserts-linux-release-x64 language/nnbd/boolean_conversion/boolean_conversion_weak_test

Will bisect locally.

tools/bisect.dart \
-Dend=262311772b2128ef778d0a1d189f0c6c51780132 \
-Dstart=751a47f942268c3c61561f4ee77466f1e5066930 \
-Dtest_command="python3 tools/test.py --build -n dartkp-weak-asserts-linux-release-x64 language/nnbd/boolean_conversion/boolean_conversion_weak_test" \
-Dfailure_string="Expect.throws(AssertionError) fails: Did not throw"

[dcharkes]

Ensuring SDK repo in /usr/local/google/home/dacoharkes/master-dart-sdk/sdk/.
Ensuring failure reproduces on 751a47f.
Commit 751a47f, reproduces failure.
Ensuring failure does not reproduce on f787597.
Commit f787597, does not reproduce failure.
Bisecting 751a47f...a211ec9 (29 commits). Trying 088b178.
Commit 088b178, reproduces failure.
Bisecting 088b178...a211ec9 (15 commits). Trying 2cce183.
Commit 2cce183, reproduces failure.
Bisecting 2cce183...a211ec9 (8 commits). Trying 682c82a.
Commit 682c82a, reproduces failure.
Bisecting 682c82a...a211ec9 (4 commits). Trying ea517c1.
Commit ea517c1, reproduces failure.
Bisecting ea517c1...a211ec9 (2 commits). Trying a211ec9.
Commit a211ec9, reproduces failure.
Bisected to a211ec9.

A build file removal, that seems a bit suspicious. Maybe this test is flaky or the bisection script is broken.

Edit: the actual cause is 2623117.

Edit 2: And git log hash1...hash2 should have been git log hash1~...hash2 to not let commit hash1 slip through.

Commit range f787597...751a47f.
Ensuring SDK repo in /usr/local/google/home/dacoharkes/master-dart-sdk/sdk/.
Ensuring failure reproduces on 751a47f.
Commit 751a47f, reproduces failure.
Ensuring failure does not reproduce on f787597.
Commit f787597, does not reproduce failure.
Bisecting f787597...751a47f (30 commits). Trying 1ecc1ba.
Commit 1ecc1ba, reproduces failure.
Bisecting f787597...1ecc1ba (15 commits). Trying abb299e.
Commit abb299e, reproduces failure.
Bisecting f787597...abb299e (8 commits). Trying 93acfda.
Commit 93acfda, reproduces failure.
Bisecting f787597...93acfda (4 commits). Trying a211ec9.
Commit a211ec9, reproduces failure.
Bisecting f787597...a211ec9 (2 commits). Trying 2623117.
Commit 2623117, reproduces failure.
Bisected to 2623117.

[dcharkes]

It's likely that the following regressions were caused by the same change. These are also all related to bools and nulls in legacy mode.

There are new test failures on [tests][web-fixit] Fix date_time_extremes_test....[cfe] Update ast-to-text.

The tests

co19/Language/Expressions/Logical_Boolean_Expressions/syntax_t01 RuntimeError (expected Pass)
co19_2/Language/Expressions/Logical_Boolean_Expressions/syntax_t01 RuntimeError (expected Pass)
language/regress/regress34147_test RuntimeError (expected Pass)
language_2/if_null/precedence_runtime_test RuntimeError (expected Pass)
language_2/regress/regress34147_test RuntimeError (expected Pass)

are failing on configurations

dartkp-linux-debug-x64
dartkp-linux-release-x64
dartkp-weak-asserts-linux-release-x64