Imported Upstream version 5.4.0.167

Former-commit-id: 5624ac747d633e885131e8349322922b6a59baaa

external/cecil/symbols/pdb/Mono.Cecil.Pdb/NativePdbReader.cs

@@ -264,6 +264,9 @@ namespace Mono.Cecil.Pdb {
 			var import = new ImportDebugInformation ();
 
 			foreach (var used_namespace in scope.usedNamespaces) {
+				if (string.IsNullOrEmpty (used_namespace))
+					continue;
+
 				ImportTarget target = null;
 				var value = used_namespace.Substring (1);
 				switch (used_namespace [0]) {

external/cecil/symbols/pdb/Mono.Cecil.Pdb/NativePdbWriter.cs

@@ -80,6 +80,10 @@ namespace Mono.Cecil.Pdb {
 			this.metadata = metadata;
 		}
 
+		void IMetadataSymbolWriter.WriteModule ()
+		{
+		}
+
 		void DefineCustomMetadata (MethodDebugInformation info, MetadataToken import_parent)
 		{
 			var metadata = new CustomMetadataWriter (this.writer);

external/cecil/symbols/pdb/Test/Mono.Cecil.Tests/PdbTests.cs

@@ -153,6 +153,13 @@ namespace Mono.Cecil.Tests {
 			}, readOnly: Platform.OnMono, symbolReaderProvider: typeof (PdbReaderProvider), symbolWriterProvider: typeof (PdbWriterProvider));
 		}
 
+		[Test]
+		public void EmptyRootNamespace ()
+		{
+			TestModule ("EmptyRootNamespace.dll", module => {
+			}, readOnly: Platform.OnMono, symbolReaderProvider: typeof(PdbReaderProvider), symbolWriterProvider: typeof(PdbWriterProvider));
+		}
+
 		[Test]
 		public void LocalVariables ()
 		{