Decompiling the following code in either DEBUG or RELEASE build gives the exception below:

        public IEnumerable<int> YieldTest(IEnumerable<int> sequenceA, List<int> sequenceB)
        {
            foreach (var i in sequenceA)
            {
                foreach (var j in sequenceB)
                {
                    yield return i*j;
                }
            }
        }

So a foreach nested inside another foreach...

Current member / type: System.Collections.Generic.IEnumerable`1<System.Int32> Tests.TestClass::YieldTest(System.Collections.Generic.IEnumerable`1<System.Int32>,System.Collections.Generic.List`1<System.Int32>)
File path: C:\Projects\Sandbox\Decompile Test\Tests\Tests\bin\Release\Tests.dll

Product version: 2019.1.118.0
Exception in: System.Collections.Generic.IEnumerable<System.Int32> YieldTest(System.Collections.Generic.IEnumerable<System.Int32>,System.Collections.Generic.List<System.Int32>)

Invalid state value
at €—..
(‚ ž, Queue`1 , ILogicalConstruct ”) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\LogicFlow\YieldGuardedBlocksBuilder.cs:line 203
at €—..Ÿ(‚ ž) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\LogicFlow\YieldGuardedBlocksBuilder.cs:line 187
at €—..(‚ ž) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\LogicFlow\YieldGuardedBlocksBuilder.cs:line 129
at €—..š(„ ‚) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\LogicFlow\YieldGuardedBlocksBuilder.cs:line 76
at €—..() in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\LogicFlow\LogicalFlowBuilderStep.cs:line 126
at €—..œ(DecompilationContext ™, •Ÿ €–) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\LogicFlow\LogicalFlowBuilderStep.cs:line 51
at ‚–.™“.(MethodBody €–, •Ÿ Ÿ, ILanguage ) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\DecompilationPipeline.cs:line 88
at ‚–.™“.‹(MethodBody €–, ILanguage ) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\DecompilationPipeline.cs:line 70
at Telerik.JustDecompiler.Decompiler.Extensions.“(MethodBody €–, DecompilationContext †, Œ Ÿ“, Func`2
”, DecompilationContext& ”“) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\Extensions.cs:line 104
at Telerik.JustDecompiler.Decompiler.Extensions.”(MethodBody €–, DecompilationContext †, ž& ž) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\Extensions.cs:line 139
at ž..–() in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Steps\RebuildYieldStatementsStep.cs:line 134
at ž..Match(‰ œ—) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Steps\RebuildYieldStatementsStep.cs:line 49
at ž..œ(DecompilationContext ™, •Ÿ €–) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Steps\RebuildYieldStatementsStep.cs:line 20
at ‚–.™“.(MethodBody €–, •Ÿ Ÿ, ILanguage ) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\DecompilationPipeline.cs:line 88
at ‚–.™“.‹(MethodBody €–, ILanguage ) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\DecompilationPipeline.cs:line 70
at Telerik.JustDecompiler.Decompiler.Extensions.›“(™“ œ“, ILanguage , MethodBody €–, DecompilationContext& ™) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\Extensions.cs:line 95
at Telerik.JustDecompiler.Decompiler.Extensions.š“(MethodBody €–, ILanguage , DecompilationContext& ™,  œ–) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\Extensions.cs:line 58
at ——.ƒ˜.—(ILanguage , MethodDefinition €,  œ–) in C:\DeveloperTooling_JD_Agent1\_work\15\s\OpenSource\Cecil.Decompiler\Decompiler\WriterContextServices\BaseWriterContextService.

I also send an email about this when I encountered it earlier but here is an actual code example.