Bug: VM service `addBreakpointWithScriptUri` and `addBreakpoint` don't add valid breakpoints for code in `dart:` libraries. See #47204
This PR contains :
- a new test : 'service/break_on_dart_colon_test.dart', that checks several URIs to register breakpoints in `dart:` libs.
- a fix in `Debugger::SetBreakpointAtLineCol` to make it calls `Library::LookupScript'` with the right value for `useResolvedUri` parameter.
Fixes https://github.com/dart-lang/sdk/issues/47204
TEST=runtime/observatory/tests/service/break_on_dart_colon_test.dart
Change-Id: Id3d6722c278e3238202a9d84a0d34612b957035c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/213766
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>
The flag isn't used anywhere in our tests or in embedder code. Turning
it on will result in a VM startup error.
We should therefore remove all uses of the flag and the flag itself.
This is a unmodified reland of
https://dart-review.googlesource.com/c/sdk/+/204500
after some remaining g3 usages have been fixed (the flutter
roll didn't port the GN changes to BUILD changes in g3)
TEST=Existing test suite.
Change-Id: Ic28c9b334a0b04524ee57e2554cc8d713a83fbfb
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/204785
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
This reverts commit b1f1aee94d.
Reason for revert: Some left-over uses in g3 need to removed first
(some were removed in b/380758599 but apparently there's some
usages left).
Original change's description:
> [vm] Remove --causal-async-stacks flag
>
> The flag isn't used anywhere in our tests or in embedder code. Turning
> it on will result in a VM startup error.
>
> We should therefore remove all uses of the flag and the flag itself.
>
> TEST=Existing test suite.
>
> Change-Id: I19dfba052df7948dfdb379c0610dab67ebbcd12d
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/204500
> Reviewed-by: Clement Skau <cskau@google.com>
> Commit-Queue: Martin Kustermann <kustermann@google.com>
TBR=kustermann@google.com,cskau@google.com
Change-Id: I03aad46f46153d5ea4ac2fcdd5685d0ef2a0d9af
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/204723
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
The flag isn't used anywhere in our tests or in embedder code. Turning
it on will result in a VM startup error.
We should therefore remove all uses of the flag and the flag itself.
TEST=Existing test suite.
Change-Id: I19dfba052df7948dfdb379c0610dab67ebbcd12d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/204500
Reviewed-by: Clement Skau <cskau@google.com>
Commit-Queue: Martin Kustermann <kustermann@google.com>
BreakpointLocation token_pos and end_token_pos are populated when
breakpoint is resolved and are read when vm needs to see if a
function has breakpoints.
Since the breakpoint is resolved once and token positions are
populated with real values only once using simple atomics is sufficient
to resolve data race.
Fixes https://github.com/dart-lang/sdk/issues/45877
TEST=service[_2]/break_on_function_many_child_isolates_test.dart on tsan
Change-Id: I92066d094ca3a86c80f0de648debea05ccde5e49
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/197561
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Alexander Aprelev <aam@google.com>
Retrieve CodeBreakpoint::ToCString() while we hold on to the CodeBreakpoint, before BreakpointLocation potentially deleted with terminated isolate.
GroupDebugger::NotifyCompilation(func) might be called several times for a given function when multiple isolates in a group race to compile it. Debugger needs to handle this scenario gracefully, ensure that already resolved breakpoints won't get resolved again.
TEST=observatory_2/tests/service_2/break_on_function_many_child_isolates_test
Fixes https://github.com/dart-lang/sdk/issues/45516.
Change-Id: Ieebab86103b1999a13daff7b7bbc87ffa778ec82
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/197520
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Alexander Aprelev <aam@google.com>
There is a synthetic try/catch within a try/finally block.
When trying to assess whether an exception is caught, the debugger
should skip such generated try/catch blocks. Otherwise, it considers
that try/finally actually handles the exception, which is wrong.
Fixes https://github.com/dart-lang/sdk/issues/45684
TEST=runtime/observatory{,_2}/tests/service{,_2}/regress_45684_test.dart
Change-Id: I60e8837204cf97ee1ab02ffd03364e7f69857004
Fixed: 45684
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/196124
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Ben Konyi <bkonyi@google.com>
objects
It's possible for scripts to appear in multiple components provided by
the front end in certain situations (e.g., mixin applications in
different libraries). Previously when trying to set a breakpoint, if
multiple scripts were found matching the target URI the debugger would
give up and not set the breakpoint.
This change allows for multiple Scripts to be associated with a
BreakpointLocation.
Fixes https://github.com/flutter/flutter/issues/66832
TEST=runtime/observatory_2/tests/service_2/sdk_break_with_mixin_test.dart
Change-Id: I935721f4753675a9a2051a71cc1720e590f8d4f6
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/195664
Commit-Queue: Ben Konyi <bkonyi@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Attempts to acquire safepoint lock while in SafepointOperationScope could result
in deadlocks if somebody else was holding that lock when they were forced to a safepoint.
Clean up few places where locks were acquired in SafepointOperationScope.
Introduce StoppedMutatorsScope and GroupDebugger::RunUnderReadLockIfNeeded that acquires
a lock only if it runs outside of StoppedMutatorsScope - to prevent such deadlocks.
Also fix tsan warning about data race around message_notify_callback by making it atomic.
TEST=tsan runs of debugger CI tests
Fixes https://github.com/dart-lang/sdk/issues/45527
Fixes https://github.com/dart-lang/sdk/issues/45549
Issue https://github.com/dart-lang/sdk/issues/36097
Change-Id: Ibb53d9ce760d869e044e17075aeebf20fc0016a5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/193582
Commit-Queue: Alexander Aprelev <aam@google.com>
Reviewed-by: Ben Konyi <bkonyi@google.com>
Keep list of all per-isolate BreakpointLocations on isolate_group so all of them
can be traversed by isolate group when function is compiled and
GroupDebugger::NotifyCompilation() is invoked.
This also fixes data race around line_number lazy-initialization.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=existing ci test suite
Change-Id: I821b49a56cdc28da8d0c0c97e7d850995285c48a
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/193380
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Alexander Aprelev <aam@google.com>
BreakpointLocation represents source code location, which can
correspond to multiple Functions(in case of some mixin method
mixed-in in several classes, for example).
BreakpointLocation is connected to a Function via CodeBreakpoint.
CodeBreakpoint represents some point in the generated Code in some
Function. BreakpointLocation connects to multiple
CodeBreakpoints - one per Function that source code location was
generated into.
This CL removes Function reference stored directly in BreakpointLocation
as it is misleading.
This CL also removes some source-code-related attributes(uri/token_pos)
stored in CodeBreakpoint. If CodeBreakpoint code needs that information
it can find it in BreakpointLocation it references.
This should help with further refactoring to support BreakpointLocation
that map to multiple scripts
TEST=ci
Change-Id: I41b82fddc5018ef7df61c9d3a3c4aee657cee528
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/192946
Commit-Queue: Alexander Aprelev <aam@google.com>
Reviewed-by: Ben Konyi <bkonyi@google.com>
CodeBreakpoint class tracks patching of the call targets for the purpose of routing the call to the debugger runtime.
With this CL CodeBreakpoint instance is managed by GroupDebugger, debugger class owned by IsolateGroup, and can be associated with multiple BreakpointLocation, one location per isolate that set a breakpoint at particular code location.
TEST=observatory/tests/service/break_on_function_child_isolate_test
Issue https://github.com/dart-lang/sdk/issues/36097
Change-Id: I3b3d0974a0fb9668742e5c1e2a2ce13b84b1d630
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/190732
Commit-Queue: Alexander Aprelev <aam@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
The async, off-stack part of DebuggerStackTrace::CollectAwaiterReturn's
stack unwinding incorrectly looked on the stack instead of following
the Closure's awaiter chain.
This caused the async stack traces to be truncated and missing any
async frames, in turn causing ShouldPauseOnException to incorrectly
conclude no handler frame existing.
This would affect any case where the exception handling was located
around any except for the inner most awaiter.
TEST=Added regression test to pause_on_unhandled_exceptions_catcherror_test
Closes: https://github.com/dart-lang/sdk/issues/37953
Bug: https://github.com/dart-lang/sdk/issues/37953
Change-Id: I34a2b5ce3c7532032b2ef3dfbc2af7294d13a4c7
Cq-Do-Not-Cancel-Tryjobs: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/187405
Commit-Queue: Clement Skau <cskau@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
This is a reland of b6dc4dad4d
TEST=ci
Original change's description:
> [vm/aot] Avoid using most Code objects in stack traces with --dwarf-stack-traces
>
> The following changes are done in preparation for the removal of Code
> objects in AOT with --dwarf-stack-traces:
>
> * Stack trace objects are extended to hold uword PCs (which may not
> fit into Smi range).
>
> * Scanning stack frames in GC (StackFrame::VisitObjectPointers)
> now avoids using Code objects.
> In order to find CompressedStackMaps it now calls
> ReversePc::FindCompressedStackMaps.
>
> * Singleton Code object (StubCode::UnknownDartCode()) is prepared as
> a replacement for Code objects in stack traces. It has
> PayloadStart() == 0 and Size() == kUwordMax so it includes
> arbitrary PCs.
>
> * In --dwarf-stack-traces mode, most Code objects obtained from stack
> frames are replaced with StubCode::UnknownDartCode().
> This simulates future behavior of ReversePc::Lookup when Code objects
> will be removed.
>
> Issue: https://github.com/dart-lang/sdk/issues/44852
> Change-Id: I7cec7b8b9396c9cfeca3c256a412ba4e82a7e0c4
> TEST=ci
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/182720
> Commit-Queue: Alexander Markov <alexmarkov@google.com>
> Reviewed-by: Tess Strickland <sstrickl@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>
Change-Id: Ia2fc4672a085cd963b7fc103369851df3603590c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/186202
Commit-Queue: Vyacheslav Egorov <vegorov@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
This reverts commit b6dc4dad4d.
Reason for revert: broke package:vm_snapshot_analysis in Flutter
(https://github.com/flutter/flutter/issues/76313).
Original change's description:
> [vm/aot] Avoid using most Code objects in stack traces with --dwarf-stack-traces
>
> The following changes are done in preparation for the removal of Code
> objects in AOT with --dwarf-stack-traces:
>
> * Stack trace objects are extended to hold uword PCs (which may not
> fit into Smi range).
>
> * Scanning stack frames in GC (StackFrame::VisitObjectPointers)
> now avoids using Code objects.
> In order to find CompressedStackMaps it now calls
> ReversePc::FindCompressedStackMaps.
>
> * Singleton Code object (StubCode::UnknownDartCode()) is prepared as
> a replacement for Code objects in stack traces. It has
> PayloadStart() == 0 and Size() == kUwordMax so it includes
> arbitrary PCs.
>
> * In --dwarf-stack-traces mode, most Code objects obtained from stack
> frames are replaced with StubCode::UnknownDartCode().
> This simulates future behavior of ReversePc::Lookup when Code objects
> will be removed.
>
> Issue: https://github.com/dart-lang/sdk/issues/44852
> Change-Id: I7cec7b8b9396c9cfeca3c256a412ba4e82a7e0c4
> TEST=ci
> Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/182720
> Commit-Queue: Alexander Markov <alexmarkov@google.com>
> Reviewed-by: Tess Strickland <sstrickl@google.com>
> Reviewed-by: Martin Kustermann <kustermann@google.com>
Issue: https://github.com/dart-lang/sdk/issues/44852
Change-Id: I6f66171eecf1133363a7ce56193e782e43a20baf
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/185488
Reviewed-by: Zach Anderson <zra@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
The following changes are done in preparation for the removal of Code
objects in AOT with --dwarf-stack-traces:
* Stack trace objects are extended to hold uword PCs (which may not
fit into Smi range).
* Scanning stack frames in GC (StackFrame::VisitObjectPointers)
now avoids using Code objects.
In order to find CompressedStackMaps it now calls
ReversePc::FindCompressedStackMaps.
* Singleton Code object (StubCode::UnknownDartCode()) is prepared as
a replacement for Code objects in stack traces. It has
PayloadStart() == 0 and Size() == kUwordMax so it includes
arbitrary PCs.
* In --dwarf-stack-traces mode, most Code objects obtained from stack
frames are replaced with StubCode::UnknownDartCode().
This simulates future behavior of ReversePc::Lookup when Code objects
will be removed.
Issue: https://github.com/dart-lang/sdk/issues/44852
Change-Id: I7cec7b8b9396c9cfeca3c256a412ba4e82a7e0c4
TEST=ci
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/182720
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
The logic for background compiler can be simplified due to:
* we only have one bg compiler
* it always optimizes
* it is allocated at isolate startup and freed on isolate shutdown
* an existing check in the compiler for whether the BG compiler is
disabled is racy and therefore not helpful
* when a mutator communicates with BG compiler it will use
SafepointMutexLocker instead of MutexLocker
This CL also ecapsulates disabling the BG compiler via a
NoBackgroundCompilerScope object. It allows nested disabling and guards
against races.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Refactoring of existing code.
Change-Id: I36ed6592c9a8b91e94181698b7de662b4ee984e9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/183400
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Currently we have things called XPtr which are not what you get from ptr().
Old world:
handle->raw() returns RawObject* (tagged)
raw_obj->ptr() returns RawObject* (untagged)
After 6fe15f6df9:
handle->raw() returns ObjectPtr
obj_ptr->ptr() returns ObjectLayout*
New world:
handle->ptr() returns ObjectPtr
obj_ptr->untag() returns UntaggedObject*
TEST=ci
Change-Id: I6c7f34014cf20737607caaf84979838300d12df2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/149367
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Siva Annamalai <asiva@google.com>
Reviewed-by: Vyacheslav Egorov <vegorov@google.com>
As part of making the compiler and other subsystems independent
of `Isolate` we have to move various state from `Isolate` to
`IsolateGroup` (or to another place).
The access of `ObjectStore::closure_functions()` was spread out over our
codebase, including from `Isolate`. This CL moves it to a centralized
place - ClosureFunctionsCache.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Pure refactoring - relying on existing test coverage.
Change-Id: I3b282623f07614cdc2c2a863bd5b9d6c7748d36f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177130
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
As part of making the compiler and other subsystems independent
of `Isolate` we have to move various state from `Isolate` to
`IsolateGroup`.
The class_table and object_store were already moved to `IsolateGroup`.
This CL only replaces usages of `Isolate::{object_store,class_table}`
with the equivalent in `IsolateGroup`.
Issue https://github.com/dart-lang/sdk/issues/36097
TEST=Pure refactoring - relying on existing test coverage.
Change-Id: I34a0682d715b054d6c5faff077a513980f59a348
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/177126
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: Alexander Aprelev <aam@google.com>
Reviewed-by: Ryan Macnak <rmacnak@google.com>
First, change LocationForPosition and TokenRangeAtLine to return
whether they successfully located the offset/line. Also change the
wrappers in Script (GetTokenLocation and TokenRangeAtLine) to return
whether or not any information was successfully located.
These methods now only change the out parameters in the case that
appropriate information was found, so any unconditional uses of the out
parameters need the out parameters to be appropriately initialized.
We now allow negative lines to be requested in TokenRangeAtLine (with
the failure behavior described above) so the line returned by
LocationAtPosition can be fed into TokenRangeAtLine without intermediate
checking.
The calculation of the token length, which uses the script source and
not the line starts array, has been moved to a new method,
Script::GetTokenLength. The new method returns the length (or a
negative value if the token length could not be determined) instead of
using an out parameter.
TEST=Existing tests on trybots, to ensure tests using current
line/number info aren't affected.
Bug: https://github.com/dart-lang/sdk/issues/44436
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-product-x64-try,vm-kernel-linux-product-x64-try,vm-kernel-linux-release-simarm-try,vm-kernel-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm64-try,vm-kernel-precomp-linux-release-simarm-try
Change-Id: Ibc048a226d11ff9a340a8d249654d07720fdf115
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/175365
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Clement Skau <cskau@google.com>
Instead, split each old use into the following cases:
* If the TokenPosition value is expected to be a real token position,
then use TokenPosition::Pos().
* If the TokenPosition is being serialized in some way, then use
TokenPosition::Serialize() and change the place where the
TokenPosition is recreated to use TokenPosition::Deserialize().
* If the value of the TokenPosition is being printed for debugging
purposes, then just use TokenPosition::ToCString() instead.
That is, we try to pin down when token positions are expected to
be real vs. when other types of token positions can be found.
Another source of possible error when using token positions is to
convert between synthetic and real token positions. In the past,
synthetic token positions may have been based off real token positions,
but that is no longer the case. Thus, all methods that allow
that conversion have been removed, and instead there is a new static
method for constructing synthetic tokens from valid nonces.
This CL also makes it so that Pos() and relational operators on token
positions are only defined on real token positions, to avoid any
assumptions about what the value encoded in synthetic positions mean. To
help with cases where non-real token positions may occur, four helper
methods are added:
* TokenPosition::Min(a, b): A static method that returns the smallest
real token position provided. If neither `a` or `b` are real,
returns `a`.
* TokenPosition::Max(a, b): A static method that returns the largest
real token position provided. If neither `a` or `b` are real,
returns `a`.
* TokenPosition::IsWithin(start, end): Determines whether `this` falls
between `start` and `end` (inclusive). If `this` is non-real, then it
must be either `start` or `end` if synthetic, otherwise false.
Otherwise, we mimic the old style of range checking, which means that
non-real starts and ends are treated as less than every real token.
* TokenPosition::CompareForSorting(other): Unlike the relational
operators, provides a comparison between any types of token positions
for purposes such as sorting. Currently only used in the profiler.
It also changes TokenPosition::ToCString() to tag synthetic token
positions, so they can be distinguished from real ones at a glance.
TEST=Existing test suite on trybots, especially the observatory tests
which make heavy use of the debugger and the unit tests for the
profiler/source report modules.
Bug: https://github.com/dart-lang/sdk/issues/44436
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-nnbd-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-nnbd-linux-debug-x64-try,vm-kernel-linux-debug-x64-try,vm-kernel-linux-release-x64-try,vm-kernel-nnbd-linux-release-x64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-nnbd-linux-release-x64-try,vm-kernel-linux-product-x64-try,vm-kernel-precomp-linux-product-x64-try
Change-Id: Ic06aa0bc7a1f0fbac7257ed22ca5e7e0ccd7f3f2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/174924
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
The Next() method on TokenPositions used to increment the internal
value_ field, but now creates a new TokenPosition with value_ + 1.
There are only three places this is used:
* Getting the token position after the end token position for
implicit closure functions in the scope builder.
* Getting the token position after the end token position for
variable declarations in the scope builder.
* Iterating over the token positions on a single source line in
the debugger.
So the overhead of creating new TokenPositions vs. mutating the original
should be limited, compared to the benefit of being able to assume
TokenPosition values are constant once created. There's too much
dependence on the copy and copy assignment operators due to the previous
possibility of mutation to make the internal field constant at the
moment without much more sweeping changes, unfortunately.
Also remove the copy assignment in initializing TokenPosition constants.
TEST=Tested using existing tests on trybots.
Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-nnbd-linux-debug-x64-try,vm-kernel-precomp-linux-debug-x64-try,vm-kernel-nnbd-linux-debug-x64-try,vm-kernel-linux-debug-x64-try,vm-kernel-linux-release-x64-try,vm-kernel-nnbd-linux-release-x64-try,vm-kernel-precomp-linux-release-x64-try,vm-kernel-precomp-nnbd-linux-release-x64-try,vm-kernel-linux-product-x64-try,vm-kernel-precomp-linux-product-x64-try
Change-Id: Ie18b7f45bd9c6a43647ecd189330d91a4dff373b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/174922
Commit-Queue: Tess Strickland <sstrickl@google.com>
Reviewed-by: Clement Skau <cskau@google.com>
All existing embedders have been opted into --lazy-async-stacks, the
VM also uses it as it's default in all configurations.
After this CL, any user of --causal-async-stacks will get an error
message when trying to use it.
=> In any such case, please simply remove the flag.
TEST=Exhaustive CQ.
Bug: https://github.com/dart-lang/sdk/issues/37668
Change-Id: Ia440afcf2dba464aa8b8cf381b93bbac8eb9f8dc
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/172564
Commit-Queue: Clement Skau <cskau@google.com>
Reviewed-by: Clement Skau <cskau@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
Bruno Leroux