Tests failed with error message: violates the constraint of type parameter 'T'.

[VincentBu]

Run: runtime-coreclr libraries-jitstress 20210629.1

Failed tests:

- System.Text.Tests.TranscodingStreamTests.Flush_FlushesInnerStreamButNotDecodedState

System.ArgumentException : Type to mock must be an interface or an abstract or non-sealed class. ---- System.TypeLoadException : GenericArguments[0], 'System.Int32', on 'System.Collections.Generic.GenericEqualityComparer`1[T]' violates the constraint of type parameter 'T'.

- System.Collections.Immutable.Tests.ImmutableSortedDictionaryTest.Remove_FirstKey_RemovesKeyValuePair

System.TypeLoadException : GenericArguments[0], 'System.Int32', on 'System.Collections.Generic.GenericEqualityComparer`1[T]' violates the constraint of type parameter 'T'.

- System.Collections.ObjectModel.Tests.PublicMethodsTest.RemoveAtTest

System.Security.VerificationException : Method System.SpanHelpers.IndexOf: type argument 'System.Int64' violates the constraint of type parameter 'T'.

- System.Collections.Tests.Queue_Generic_Tests_int.IGenericSharedAPI_Add_AfterRemovingAnyValue(count: 1)

System.TypeLoadException : GenericArguments[0], 'System.Int32', on 'System.Collections.Generic.GenericEqualityComparer`1[T]' violates the constraint of type parameter 'T'.

- System.Diagnostics.Tests.StackTraceTests.ToString_ShowILOffset

System.TypeLoadException : GenericArguments[0], 'System.Int32', on 'System.Collections.Generic.GenericEqualityComparer`1[T]' violates the constraint of type parameter 'T'.

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[VincentBu]

Also failed in runtime-coreclr libraries-jitstress 20210630.1

Failed tests:

net6.0-Linux-Release-arm-CoreCLR_checked-jitminopts-(Ubuntu.1804.Arm32.Open)Ubuntu.1804.Armarch.Open@mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-18.04-helix-arm32v7-bfcd90a-20200121150440

- System.Globalization.ISOWeekTests.GetWeeksInYear
- System.Globalization.ISOWeekTests.GetWeekOfYear
- System.Globalization.ISOWeekTests.GetYear
- System.Globalization.ISOWeekTests.GetYearEnd
- System.Globalization.ISOWeekTests.GetYearStart
- System.Globalization.ISOWeekTests.ToDateTime

Error message
System.TypeInitializationException : The type initializer for 'System.Globalization.ISOWeekTests' threw an exception.
---- System.TypeLoadException : GenericArguments[0], 'System.Int32', on 'System.Collections.Generic.GenericEqualityComparer`1[T]' violates the constraint of type parameter 'T'.


Stack trace
   at System.Globalization.ISOWeekTests.GetWeeksInYear() in /_/src/libraries/System.Globalization.Calendars/tests/ISOWeek/ISOWeekTests.cs:line 140
----- Inner Stack Trace -----
   at System.Collections.Generic.HashSet`1.AddIfNotPresent(T value, Int32& location)
   at System.Collections.Generic.HashSet`1.Add(T item) in /_/src/libraries/System.Private.CoreLib/src/System/Collections/Generic/HashSet.cs:line 455
   at System.Globalization.ISOWeekTests..cctor() in /_/src/libraries/System.Globalization.Calendars/tests/ISOWeek/ISOWeekTests.cs:line 14

net6.0-Linux-Release-arm64-CoreCLR_checked-jitminopts-(Ubuntu.1804.Arm64.Open)Ubuntu.1804.Armarch.Open@mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-18.04-helix-arm64v8-20210531091519-97d8652

- System.Text.Encodings.Web.Tests.TextEncoderSettingsTests.GetAllowedCodePoints

Error message
System.TypeLoadException : GenericArguments[0], 'System.Int32', on 'System.Collections.Generic.GenericEqualityComparer`1[T]' violates the constraint of type parameter 'T'.


Stack trace
   at System.Collections.Generic.HashSet`1.AddIfNotPresent(T value, Int32& location)
   at System.Collections.Generic.HashSet`1.UnionWith(IEnumerable`1 other) in /_/src/libraries/System.Private.CoreLib/src/System/Collections/Generic/HashSet.cs:line 494
   at System.Collections.Generic.HashSet`1..ctor(IEnumerable`1 collection, IEqualityComparer`1 comparer) in /_/src/libraries/System.Private.CoreLib/src/System/Collections/Generic/HashSet.cs:line 103
   at System.Linq.Enumerable.ExceptIterator[TSource](IEnumerable`1 first, IEnumerable`1 second, IEqualityComparer`1 comparer)+MoveNext() in /_/src/libraries/System.Linq/src/System/Linq/Except.cs:line 62
   at System.Collections.Generic.EnumerableHelpers.ToArray[T](IEnumerable`1 source, Int32& length) in /_/src/libraries/Common/src/System/Collections/Generic/EnumerableHelpers.cs:line 41
   at System.Linq.Buffer`1..ctor(IEnumerable`1 source) in /_/src/libraries/System.Linq/src/System/Linq/Buffer.cs:line 38
   at System.Linq.OrderedEnumerable`1.ToArray() in /_/src/libraries/System.Linq/src/System/Linq/OrderedEnumerable.SpeedOpt.cs:line 14
   at System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source) in /_/src/libraries/System.Linq/src/System/Linq/ToCollection.cs:line 17
   at System.Text.Encodings.Web.Tests.TextEncoderSettingsTests.GetAllowedCodePoints() in /_/src/libraries/System.Text.Encodings.Web/tests/TextEncoderSettingsTests.cs:line 394

[VincentBu]

Many tests failed with same error message:
System.TypeLoadException : GenericArguments[0], 'System.Int32', on 'System.Collections.Generic.GenericEqualityComparer`1[T]' violates the constraint of type parameter 'T'.

Run : runtime-coreclr libraries-jitstress 20210701.1

Failed tests:

net6.0-windows-Release-arm64-CoreCLR_checked-jitminopts-Windows.10.Arm64v8.Open

- System.ComponentModel.Composition.Registration.Tests.*

net6.0-Linux-Release-arm-CoreCLR_checked-jitminopts-(Ubuntu.1804.Arm32.Open)Ubuntu.1804.Armarch.Open@mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-18.04-helix-arm32v7-bfcd90a-20200121150440

- XPathTests.FunctionalTests.Location.Paths.MiscWithEncodingTests.MatchesTest1138
- System.Xml.Linq.Tests.RegressionTests.CreatingXElementsFromNewDev10Types

net6.0-Linux-Release-arm64-CoreCLR_checked-jitminopts-(Ubuntu.1804.Arm64.Open)Ubuntu.1804.Armarch.Open@mcr.microsoft.com/dotnet-buildtools/prereqs:ubuntu-18.04-helix-arm64v8-20210531091519-97d8652

- System.Linq.Tests.*

One of error messages:

System.TypeLoadException : GenericArguments[0], 'System.Int32', on 'System.Collections.Generic.GenericEqualityComparer`1[T]' violates the constraint of type parameter 'T'.


Stack trace
   at System.Collections.Generic.HashSet`1.AddIfNotPresent(T value, Int32& location)
   at System.Collections.Generic.HashSet`1.Add(T item) in /_/src/libraries/System.Private.CoreLib/src/System/Collections/Generic/HashSet.cs:line 455
   at System.Linq.Tests.TestExtensions.RunOnceList`1.AssertAll() in /_/src/libraries/System.Linq/tests/TestExtensions.cs:line 46
   at System.Linq.Tests.TestExtensions.RunOnceList`1.CopyTo(T[] array, Int32 arrayIndex) in /_/src/libraries/System.Linq/tests/TestExtensions.cs:line 86
   at System.Collections.Generic.EnumerableHelpers.ToArray[T](IEnumerable`1 source, Int32& length) in /_/src/libraries/Common/src/System/Collections/Generic/EnumerableHelpers.cs:line 20
   at System.Linq.Buffer`1..ctor(IEnumerable`1 source) in /_/src/libraries/System.Linq/src/System/Linq/Buffer.cs:line 38
   at System.Linq.OrderedEnumerable`1.GetEnumerator()+MoveNext() in /_/src/libraries/System.Linq/src/System/Linq/OrderedEnumerable.cs:line 24
   at System.Linq.Tests.ThenByTests.RunOnce() in /_/src/libraries/System.Linq/tests/ThenByTests.cs:line 142

[JulieLeeMSFT]

@BruceForstall PTAL. This test is failing repeatedly.

[BruceForstall]

@stephentoub Does this look to you like a libraries test issue, or a CLR issue?

[stephentoub]

Just from the exception, and the various unrelated tests it manifests on, I'd guess runtime.

[vlada-shubina]

Not sure if it's related or not, however dotnet/templating CI started intermittently failing after this update dotnet/templating#3387 with similar message.
The issue is intermittent and fails CI at 50% rate at the moment.
Standard_Console_Output (7).log

I'll revert the runtime update to see if it helps to fight the issue and try to upgrade to Newtonsoft.Json / NuGet to see if it helps.