Crash in compiler when compiling leap.dart (flaky)

[whesse]

A crash on the buildbot, that only occurred once, showed the compiler crashing:

../../out/ReleaseIA32/dart-sdk/lib/async/future.dart:764:1:
Internal Error: The compiler crashed when compiling this element.
Object _nonNullError(Object error) =>
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The compiler is broken.

When compiling the above element, the compiler crashed. It is not
possible to tell if this is caused by a problem in your program or
not. Regardless, the compiler should not crash.

The Dart team would greatly appreciate if you would take a moment to
report this problem at http://dartbug.com/new.

Please include the following information:

• the name and version of your operating system,
• the Dart SDK build number (1.18.0-edge.17e0b56025bdc6e03e56dabd4f0efd1b37cc279b), and
• the entire message you see here (including the full stack trace
  below as well as the source location above).

The compiler crashed: Bad state: no elements
#0 Link.head (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/util/link.dart:8)
#1 OrderedTypeSet.forEach (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/ordered_typeset.dart:98)
#2 Types.computeLeastUpperBoundInterfaces.getSupertypesAtDepth (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/dart_types.dart:1580)
#3 Types.computeLeastUpperBoundInterfaces (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/dart_types.dart:1590)
#4 Types.computeLeastUpperBound (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/dart_types.dart:1713)
#5 TypeCheckerVisitor.visitConditional (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/typechecker.dart:1834)
#6 Conditional.accept (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/tree/nodes.dart:951)
#7 TypeCheckerVisitor.analyze (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/typechecker.dart:441)
#8 TypeCheckerVisitor.visitReturn (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/typechecker.dart:1709)
#9 Return.accept (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/tree/nodes.dart:1511)
#10 TypeCheckerVisitor.analyze (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/typechecker.dart:441)
#11 TypeCheckerVisitor.visitFunctionExpression (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/typechecker.dart:666)
#12 FunctionExpression.accept (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/tree/nodes.dart:1111)
#13 TypeCheckerTask.check.. (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/typechecker.dart:68)
#14 CompilerTask.measure (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/common/tasks.dart:58)
#15 TypeCheckerTask.check. (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/typechecker.dart:62)
#16 CompilerDiagnosticReporter.withCurrentElement (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:1563)
#17 TypeCheckerTask.check (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/typechecker.dart:61)
#18 _CompilerResolution.computeWorldImpact. (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:2020)
#19 _HashVMBase&MapMixin&&_LinkedHashMapMixin.putIfAbsent (dart:collection-patch/compact_hash.dart:259)
#20 _CompilerResolution.computeWorldImpact (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:2001)
#21 Compiler.analyzeElement. (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:1053)
#22 CompilerTask.measureSubtask (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/common/tasks.dart:171)
#23 Compiler.analyzeElement (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:1040)
#24 Compiler.analyze. (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:1075)
#25 CompilerTask.measureSubtask (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/common/tasks.dart:171)
#26 Compiler.analyze (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:1057)
#27 ResolutionWorkItem.run (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/common/resolution.dart:43)
#28 Compiler.emptyQueue..... (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:961)
#29 CompilerTask.measureSubtask (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/common/tasks.dart:171)
#30 Compiler.emptyQueue.... (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:960)
#31 CompilerTask.measureSubtask (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/common/tasks.dart:171)
#32 Compiler.emptyQueue... (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:957)
#33 CompilerDiagnosticReporter.withCurrentElement (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:1563)
#34 Compiler.emptyQueue.. (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:955)
#35 QueueFilter.processWorkItem (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/enqueue.dart:954)
#36 Enqueuer.forEach (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/enqueue.dart:645)
#37 Compiler.emptyQueue. (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:954)
#38 CompilerTask.measureSubtask (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/common/tasks.dart:171)
#39 Compiler.emptyQueue (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:953)
#40 Compiler.processQueue. (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:990)
#41 CompilerTask.measureSubtask (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/common/tasks.dart:171)
#42 Compiler.processQueue (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:967)
#43 Compiler.compileLoadedLibraries. (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:841)
#44 CompilerTask.measureSubtask (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/common/tasks.dart:171)
#45 Compiler.compileLoadedLibraries (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:797)
#46 Compiler.runInternal. (file:///b/build/slave/dart2js-linux-drt-2-2-be/build/sdk/pkg/compiler/lib/src/compiler.dart:707)
#47 _RootZone.runUnary (dart:async/zone.dart:1204)
#48 _FutureListener.handleValue (dart:async/future_impl.dart:131)
#49 _Future._propagateToListeners.handleValueCallback (dart:async/future_impl.dart:637)
#50 _Future._propagateToListeners (dart:async/future_impl.dart:667)
#51 _Future._completeWithValue (dart:async/future_impl.dart:477)
#52 _Future._asyncComplete. (dart:async/future_impl.dart:528)
#53 _microtaskLoop (dart:async/schedule_microtask.dart:41)
#54 _startMicrotaskLoop (dart:async/schedule_microtask.dart:50)
#55 _runPendingImmediateCallback (dart:isolate-patch/isolate_patch.dart:96)
#56 _RawReceivePortImpl._handleMessage (dart:isolate-patch/isolate_patch.dart:149)

make: *** [out/ReleaseIA32/obj/gen/leap.dart.js] Error 253

[fsc8000]

I tried reproducing this again by compiling leap.dart in a loop for a while to check if this could be a VM issue, but it seems not reproducible anymore, and I have not seen it occur on the buildbot again either.