[mtouch] Store a list of members for each native symbol.

There might be more than one member for each P/Invoke symbol, so make sure to
keep track of every one of them.

tools/common/DerivedLinkContext.cs

@@ -7,13 +7,22 @@ namespace Xamarin.Tuner
 {
 	public class DerivedLinkContext : LinkContext
 	{
-		Dictionary<string, MemberReference> required_symbols;
+		Dictionary<string, List<MemberReference>> required_symbols;
 		List<MethodDefinition> marshal_exception_pinvokes;
 
-		public Dictionary<string, MemberReference> RequiredSymbols {
+
+		public List<MemberReference> GetRequiredSymbolList (string symbol)
+		{
+			List<MemberReference> rv;
+			if (!RequiredSymbols.TryGetValue (symbol, out rv))
+				required_symbols [symbol] = rv = new List<MemberReference> ();
+			return rv;
+		}
+
+		public Dictionary<string, List<MemberReference>> RequiredSymbols {
 			get {
 				if (required_symbols == null)
-					required_symbols = new Dictionary<string, MemberReference> ();
+					required_symbols = new Dictionary<string, List<MemberReference>> ();
 				return required_symbols;
 			}
 		}

tools/linker/MonoTouch.Tuner/ListExportedSymbols.cs

@@ -17,6 +17,12 @@ namespace MonoTouch.Tuner
 		PInvokeWrapperGenerator state;
 		bool skip_sdk_assemblies;
 
+		public DerivedLinkContext DerivedLinkContext {
+			get {
+				return (DerivedLinkContext) Context;
+			}
+		}
+
 		internal ListExportedSymbols (PInvokeWrapperGenerator state, bool skip_sdk_assemblies = false)
 		{
 			this.state = state;
@@ -67,7 +73,7 @@ namespace MonoTouch.Tuner
 			if (method.IsPInvokeImpl && method.HasPInvokeInfo) {
 				var pinfo = method.PInvokeInfo;
 				if (pinfo.Module.Name == "__Internal")
-					((DerivedLinkContext) Context).RequiredSymbols [pinfo.EntryPoint] = method;
+					DerivedLinkContext.GetRequiredSymbolList (pinfo.EntryPoint).Add (method);
 
 				if (state != null) {
 					switch (pinfo.EntryPoint) {
@@ -89,7 +95,7 @@ namespace MonoTouch.Tuner
 				object symbol;
 				// The Field attribute may have been linked away, but we've stored it in an annotation.
 				if (property != null && Context.Annotations.GetCustomAnnotations ("ExportedFields").TryGetValue (property, out symbol)) {
-					((DerivedLinkContext) Context).RequiredSymbols[(string) symbol] = property;
+					DerivedLinkContext.GetRequiredSymbolList ((string) symbol).Add (property);
 				}
 			}
 		}

tools/mtouch/Application.cs

@@ -1256,8 +1256,9 @@ namespace Xamarin.Bundler {
 																"Native linking failed, undefined Objective-C class: {0}. The symbol '{1}' could not be found in any of the libraries or frameworks linked with your application.",
 							                                    symbol.Replace ("_OBJC_CLASS_$_", ""), symbol));
 						} else {
-							var member = target.GetMemberForSymbol (symbol.Substring (1));
-							if (member != null) {
+							var members = target.GetMembersForSymbol (symbol.Substring (1));
+							if (members != null && members.Count > 0) {
+								var member = members.First (); // Just report the first one.
 								// Neither P/Invokes nor fields have IL, so we can't find the source code location.
 								errors.Add (new MonoTouchException (5214, error,
 									"Native linking failed, undefined symbol: {0}. " +

tools/mtouch/Target.cs

@@ -167,8 +167,8 @@ namespace Xamarin.Bundler
 				Frameworks.Add ("CFNetwork"); // required by xamarin_start_wwan
 		}
 
-		Dictionary<string, MemberReference> entry_points;
-		public IDictionary<string, MemberReference> GetEntryPoints ()
+		Dictionary<string, List<MemberReference>> entry_points;
+		public IDictionary<string, List<MemberReference>> GetEntryPoints ()
 		{
 			if (entry_points == null)
 				GetRequiredSymbols ();
@@ -182,7 +182,7 @@ namespace Xamarin.Bundler
 
 			var cache_location = Path.Combine (App.Cache.Location, "entry-points.txt");
 			if (cached_link || !any_assembly_updated) {
-				entry_points = new Dictionary<string, MemberReference> ();
+				entry_points = new Dictionary<string, List<MemberReference>> ();
 				foreach (var ep in File.ReadAllLines (cache_location))
 					entry_points.Add (ep, null);
 			} else {
@@ -191,7 +191,7 @@ namespace Xamarin.Bundler
 					// This happens when using the simlauncher and the msbuild tasks asked for a list
 					// of symbols (--symbollist). In that case just produce an empty list, since the
 					// binary shouldn't end up stripped anyway.
-					entry_points = new Dictionary<string, MemberReference> ();
+					entry_points = new Dictionary<string, List<MemberReference>> ();
 					marshal_exception_pinvokes = new List<MethodDefinition> ();
 				} else {
 					entry_points = LinkContext.RequiredSymbols;
@@ -214,9 +214,24 @@ namespace Xamarin.Bundler
 			return entry_points.Keys;
 		}
 
-		public MemberReference GetMemberForSymbol (string symbol)
+		public IEnumerable<string> GetRequiredSymbols (Assembly assembly, bool includeObjectiveCClasses)
 		{
-			MemberReference rv = null;
+			if (entry_points == null)
+				GetRequiredSymbols ();
+
+			foreach (var ep in entry_points) {
+				if (ep.Value == null)
+					continue;
+				foreach (var mr in ep.Value) {
+					if (mr.Module.Assembly == assembly.AssemblyDefinition)
+						yield return ep.Key;
+				}
+			}
+		}
+
+		public List<MemberReference> GetMembersForSymbol (string symbol)
+		{
+			List<MemberReference> rv = null;
 			entry_points?.TryGetValue (symbol, out rv);
 			return rv;
 		}