Exception: No pending assemblies queued for compilation and no compilers running. in 2019.3b5

Unity Engine
,
1

Since updating to 2019.3.0b5 I endlessly get this error:

Exception: No pending assemblies queued for compilation and no compilers running. Compilation will never finish.
UnityEditor.Scripting.ScriptCompilation.CompilationTask.QueuePendingAssemblies () (at /Users/builduser/buildslave/unity/build/Editor/Mono/Scripting/ScriptCompilation/CompilationTask.cs:367)
UnityEditor.Scripting.ScriptCompilation.CompilationTask.Poll () (at /Users/builduser/buildslave/unity/build/Editor/Mono/Scripting/ScriptCompilation/CompilationTask.cs:256)
UnityEditor.Scripting.ScriptCompilation.EditorCompilation.PollCompilation () (at /Users/builduser/buildslave/unity/build/Editor/Mono/Scripting/ScriptCompilation/EditorCompilation.cs:1926)
UnityEditor.Scripting.ScriptCompilation.EditorCompilation.TickCompilationPipeline (UnityEditor.Scripting.ScriptCompilation.EditorScriptCompilationOptions options, UnityEditor.BuildTargetGroup platformGroup, UnityEditor.BuildTarget platform) (at /Users/builduser/buildslave/unity/build/Editor/Mono/Scripting/ScriptCompilation/EditorCompilation.cs:1919)
UnityEditor.Scripting.ScriptCompilation.EditorCompilationInterface+<>c__DisplayClass49_0.<TickCompilationPipeline>b__0 () (at /Users/builduser/buildslave/unity/build/Editor/Mono/Scripting/ScriptCompilation/EditorCompilationInterface.cs:390)
UnityEditor.Scripting.ScriptCompilation.EditorCompilationInterface.EmitExceptionAsError[T] (System.Func`1[TResult] func, T returnValue) (at /Users/builduser/buildslave/unity/build/Editor/Mono/Scripting/ScriptCompilation/EditorCompilationInterface.cs:97)
UnityEditor.Scripting.ScriptCompilation.EditorCompilationInterface:TickCompilationPipeline(EditorScriptCompilationOptions, BuildTargetGroup, BuildTarget) (at /Users/builduser/buildslave/unity/build/Editor/Mono/Scripting/ScriptCompilation/EditorCompilationInterface.cs:390)
2

Could you report a bug on this?

This exception should never be emitted and shows that there is a bug in the compilation pipeline. We would need a repro project in order to be able to fix it.

3

Deleting parts of my Library cleared the error so I can’t reproduce it alas.

4

I also get this after every Unity 2019.3.bx upgrade…

Exception: No pending assemblies queued for compilation and no compilers running. Compilation will never finish.
etc…

Followed by
Assembly with cyclic references detected (Packages/com.unity.cinemachine/Runtime/com.unity.cinemachine.asmdef)
Assembly with cyclic references detected (Packages/com.unity.render-pipelines.universal/Runtime/Unity.RenderPipelines.Universal.Runtime.asmdef)

So anything URP related is unusable in 2019.3.bx since the scripts fail to load / work.
Creating URP assets is not accessible anymore.

5

It would be very helpful if you could submit a bug report with a minimal reproduction project for this issue.

This is a known issue and we’re working on a fix. Related forum thread: https://discussions.unity.com/t/764277

6

also getting this in 2019.3.7, I believe the error is because of a circular reference (I made the mistake of reference 2 projects to each other before remove the first one):

Exception: No pending assemblies queued for compilation and no compilers running. Compilation will never finish.
UnityEditor.Scripting.ScriptCompilation.CompilationTask.QueuePendingAssemblies () (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEditor.Scripting.ScriptCompilation.CompilationTask.Poll () (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilation.PollCompilation () (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilation.TickCompilationPipeline (UnityEditor.Scripting.ScriptCompilation.EditorScriptCompilationOptions options, UnityEditor.BuildTargetGroup platformGroup, UnityEditor.BuildTarget platform) (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilationInterface+<>c__DisplayClass50_0.b__0 () (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilationInterface.EmitExceptionAsError[T] (System.Func`1[TResult] func, T returnValue) (at <78f1ad0f25c84e3ca853e639f50d95f5>:0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilationInterface:TickCompilationPipeline(EditorScriptCompilationOptions, BuildTargetGroup, BuildTarget)

7

Same error in 2020.2.0f1

Exception: No pending assemblies queued for compilation and no compilers running. Compilation will never finish.
UnityEditor.Scripting.ScriptCompilation.CompilationTask.QueuePendingAssemblies () (at :0)
UnityEditor.Scripting.ScriptCompilation.CompilationTask.Poll () (at :0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilation.CompileScriptAssemblies (UnityEditor.Scripting.ScriptCompilation.ScriptAssembly[ ] scriptAssemblies, UnityEditor.Scripting.ScriptCompilation.ScriptAssemblySettings scriptAssemblySettings, System.String tempBuildDirectory, UnityEditor.Scripting.ScriptCompilation.CompilationTaskOptions compilationTaskOptions, UnityEditor.Scripting.ScriptCompilation.EditorCompilation+CompileScriptAssembliesOptions compileScriptAssembliesOptions) (at :0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilation.CompileScriptsWithSettings (UnityEditor.Scripting.ScriptCompilation.ScriptAssemblySettings scriptAssemblySettings, System.String tempBuildDirectory, UnityEditor.Scripting.ScriptCompilation.TargetAssembly[ ]& notCompiledTargetAssemblies, System.String[ ]& notCompiledScripts, UnityEditor.Scripting.ScriptCompilation.CompilationTaskOptions compilationTaskOptions) (at :0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilation.CompileScripts (UnityEditor.Scripting.ScriptCompilation.EditorScriptCompilationOptions editorScriptCompilationOptions, UnityEditor.BuildTargetGroup platformGroup, UnityEditor.BuildTarget platform, System.String[ ] extraScriptingDefines, UnityEditor.Scripting.ScriptCompilation.CompilationTaskOptions compilationTaskOptions) (at :0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilation.TickCompilationPipeline (UnityEditor.Scripting.ScriptCompilation.EditorScriptCompilationOptions options, UnityEditor.BuildTargetGroup platformGroup, UnityEditor.BuildTarget platform, System.String[ ] extraScriptingDefines) (at :0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilationInterface.TickCompilationPipeline (UnityEditor.Scripting.ScriptCompilation.EditorScriptCompilationOptions options, UnityEditor.BuildTargetGroup platformGroup, UnityEditor.BuildTarget platform, System.String[ ] extraScriptingDefines) (at :0)
UnityEditor.Scripting.ScriptCompilation.EditorCompilationInterface:TickCompilationPipeline(EditorScriptCompilationOptions, BuildTargetGroup, BuildTarget, String[ ])

8

It is somehow related to cyclic dependencies.

2 Likes
9

How did you do that
please explain