Class compiles in MonoDevelop Unity 3.5 full profile and VisualStudio but not Unity 5.4.0 - Unity bug 834988

AbstractGenericProtected.cs

using System;

namespace MiscCSharp {
	public static class AbstractGenericProtected {

		public static void Main(string[] args) {
			var debugGraph = new DebugGraph { start = 5, end = 4, numRecords = 10 };
			var floatSeries = new FloatSeries(debugGraph, "series1");
			floatSeries.doStuff();
			System.Console.WriteLine("All done");
		}

	}

	public abstract class Series<T> {
		internal DebugGraph owner;

		/// <summary>
		/// Whether <see cref="DebugGraph"/> should set the old values to false after they wrap.
		/// Must be implemented in concrete sub-class' <see cref="renderRecords"/>.
		/// </summary>
		internal AutoClearType autoClearOld;

		/// <summary>
		/// The value written when <see cref="autoClearOld"/> <see cref="AutoClearType.Default"/> enabled.
		/// A public member so arbitrary values can be assigned.
		/// </summary>
		public T defaultValue = default(T);

		internal readonly T[] records;

		public int currentIndex { get { return owner.start; } }

		public int nextIndexToBeWritten { get { return owner.end; } }

		/// <summary>
		/// Initializes a new instance of the <see cref="DebugGraph.Series"/> class.
		/// </summary>
		protected Series(DebugGraph owner, string name, AutoClearType autoClearOld = AutoClearType.Default) {
			this.owner = owner;
			this.autoClearOld = autoClearOld;
			this.records = new T[owner.numRecords];
		}

		public void doStuff() {
			doAutoClear(); // test calling it
		}

		public void doAutoClear() {
			switch (autoClearOld) {
				case AutoClearType.None:
					break;

				case AutoClearType.Default:
					records[nextIndexToBeWritten] = defaultValue; // error CS0103: The name `nextIndexToBeWritten' does not exist in the current context
					break;

				case AutoClearType.Previous:
					records[nextIndexToBeWritten] = records[currentIndex]; // error CS0103: The name `currentIndex' does not exist in the current context (and `nextIndexToBeWritten')
					break;

				default:
					throw new System.NotImplementedException(string.Format("{0} '{1}'", typeof(AutoClearType).Name, autoClearOld));
			}
		}

	}

	public class FloatSeries : Series<float> {

		internal FloatSeries(DebugGraph owner, string name, AutoClearType autoClearOld = AutoClearType.Default) : base(owner, name, autoClearOld) {
		}

	}

	// Version without Generics as contrast.
	public abstract class SeriesNonGeneric {
		internal DebugGraph owner;

		/// <summary>
		/// Whether <see cref="DebugGraph"/> should set the old values to false after they wrap.
		/// Must be implemented in concrete sub-class' <see cref="renderRecords"/>.
		/// </summary>
		internal AutoClearType autoClearOld;

		/// <summary>
		/// The value written when <see cref="autoClearOld"/> <see cref="AutoClearType.Default"/> enabled.
		/// A public member so arbitrary values can be assigned.
		/// </summary>
		public float defaultValue = 0f;

		internal readonly float[] records;

		public int currentIndex { get { return owner.start; } }

		public int nextIndexToBeWritten { get { return owner.end; } }

		/// <summary>
		/// Initializes a new instance of the <see cref="DebugGraph.Series"/> class.
		/// </summary>
		protected SeriesNonGeneric(DebugGraph owner, string name, AutoClearType autoClearOld = AutoClearType.Default) {
			this.owner = owner;
			this.autoClearOld = autoClearOld;
			this.records = new float[owner.numRecords];
		}

		public void doStuff() {
			doAutoClear(); // test calling it
		}

		public void doAutoClear() {
			switch (autoClearOld) {
				case AutoClearType.None:
					break;

				case AutoClearType.Default:
					records[nextIndexToBeWritten] = defaultValue; // error CS0103: The name `nextIndexToBeWritten' does not exist in the current context
					break;

				case AutoClearType.Previous:
					records[nextIndexToBeWritten] = records[currentIndex]; // error CS0103: The name `currentIndex' does not exist in the current context (and `nextIndexToBeWritten')
					break;

				default:
					throw new System.NotImplementedException(string.Format("{0} '{1}'", typeof(AutoClearType).Name, autoClearOld));
			}
		}

	}

	public class FloatSeriesNonGenerics : SeriesNonGeneric {

		internal FloatSeriesNonGenerics(DebugGraph owner, string name, AutoClearType autoClearOld = AutoClearType.Default) : base(owner, name, autoClearOld) {
		}

	}

	public class DebugGraph {
		public int start;
		
		public int end;

		public int numRecords;
	}

	/// <summary>
	/// Whether to clear the next value to be written (and values that have fallen off left side).
	/// </summary>
	public enum AutoClearType {
		/// <summary>
		/// Do no clearing.
		/// </summary>
		None,
		/// <summary>
		/// Assign the 'default' value.
		/// </summary>
		Default,
		/// <summary>
		/// Assign the previous value.
		/// </summary>
		Previous,
	}

}