diff --git a/src/Compilers/VisualBasic/Portable/BasicCodeAnalysis.vbproj b/src/Compilers/VisualBasic/Portable/BasicCodeAnalysis.vbproj
index 01c41ca224d909a2f151bc7c2ad985284fafb404..c0c40fb4981fbff1679b380ce9326cde4f5517b3 100644
--- a/src/Compilers/VisualBasic/Portable/BasicCodeAnalysis.vbproj
+++ b/src/Compilers/VisualBasic/Portable/BasicCodeAnalysis.vbproj
@@ -10,7 +10,7 @@
     <AssemblyName>Microsoft.CodeAnalysis.VisualBasic</AssemblyName>
     <TargetFramework>netstandard1.3</TargetFramework>
     <ServiceablePackage>true</ServiceablePackage>
-    <NoWarn>$(NoWarn);42014;40057;42016;41999</NoWarn>
+    <NoWarn>$(NoWarn);42014;40057</NoWarn>
     <CodeAnalysisRuleSet>..\BasicCodeAnalysisRules.ruleset</CodeAnalysisRuleSet>
     <!-- This is required to prevent downgrade references from CscCore/VbcCode since we must
          reference Microsoft.NETCore.App to target the shared framework (bug
diff --git a/src/Compilers/VisualBasic/Portable/Compilation/VisualBasicCompilation.vb b/src/Compilers/VisualBasic/Portable/Compilation/VisualBasicCompilation.vb
index 3e3947ff044565c6233331b7eccc21e4fed5429d..19c0e78b86ca6909db7a23e2c4e45dc9a5119aec 100644
--- a/src/Compilers/VisualBasic/Portable/Compilation/VisualBasicCompilation.vb
+++ b/src/Compilers/VisualBasic/Portable/Compilation/VisualBasicCompilation.vb
@@ -245,7 +245,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic
                             Debug.Assert(tree IsNot VisualBasicSyntaxTree.Dummy)
                             Debug.Assert(tree.IsMyTemplate)
 
-                            Interlocked.CompareExchange(_lazyMyTemplate, tree, VisualBasicSyntaxTree.Dummy)
+                            Interlocked.CompareExchange(Of SyntaxTree)(_lazyMyTemplate, tree, VisualBasicSyntaxTree.Dummy)
                         Else
                             ' we need to make one.
                             Dim text As String = EmbeddedResources.VbMyTemplateText
@@ -260,7 +260,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic
                                 Throw ExceptionUtilities.Unreachable
                             End If
 
-                            If Interlocked.CompareExchange(_lazyMyTemplate, tree, VisualBasicSyntaxTree.Dummy) Is VisualBasicSyntaxTree.Dummy Then
+                            If Interlocked.CompareExchange(Of SyntaxTree)(_lazyMyTemplate, tree, VisualBasicSyntaxTree.Dummy) Is VisualBasicSyntaxTree.Dummy Then
                                 ' set global cache
                                 s_myTemplateCache(parseOptions) = tree
                             End If
diff --git a/src/Compilers/VisualBasic/Portable/Emit/EditAndContinue/VisualBasicSymbolMatcher.vb b/src/Compilers/VisualBasic/Portable/Emit/EditAndContinue/VisualBasicSymbolMatcher.vb
index 32e5fa5769498a9f5d1254afb0e328545e02a319..815b55c770ffab48acd48ccd82199667265e272a 100644
--- a/src/Compilers/VisualBasic/Portable/Emit/EditAndContinue/VisualBasicSymbolMatcher.vb
+++ b/src/Compilers/VisualBasic/Portable/Emit/EditAndContinue/VisualBasicSymbolMatcher.vb
@@ -134,7 +134,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Emit
                             typesByName.Add(type.Name, type)
                         End If
                     Next
-                    Interlocked.CompareExchange(Me._lazyTopLevelTypes, typesByName, Nothing)
+                    Interlocked.CompareExchange(Of IReadOnlyDictionary(Of String, Cci.INamespaceTypeDefinition))(Me._lazyTopLevelTypes, typesByName, Nothing)
                 End If
                 Return Me._lazyTopLevelTypes
             End Function
diff --git a/src/Compilers/VisualBasic/Portable/Symbols/Source/SourceLambdaSymbol.vb b/src/Compilers/VisualBasic/Portable/Symbols/Source/SourceLambdaSymbol.vb
index 8b2c68f7619ea231b9bfb7cafa7783a1739363f2..15b986a2f43a5924e0e5f9df66c7723b6d5b98ae 100644
--- a/src/Compilers/VisualBasic/Portable/Symbols/Source/SourceLambdaSymbol.vb
+++ b/src/Compilers/VisualBasic/Portable/Symbols/Source/SourceLambdaSymbol.vb
@@ -55,7 +55,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Symbols
             Get
                 If Me._lazyAnonymousDelegateSymbol Is ErrorTypeSymbol.UnknownResultType Then
                     Dim newValue As NamedTypeSymbol = MakeAssociatedAnonymousDelegate()
-                    Dim oldValue As NamedTypeSymbol = Interlocked.CompareExchange(Me._lazyAnonymousDelegateSymbol, newValue, ErrorTypeSymbol.UnknownResultType)
+                    Dim oldValue As NamedTypeSymbol = Interlocked.CompareExchange(Of NamedTypeSymbol)(Me._lazyAnonymousDelegateSymbol, newValue, ErrorTypeSymbol.UnknownResultType)
                     Debug.Assert(oldValue Is ErrorTypeSymbol.UnknownResultType OrElse oldValue Is newValue)
                 End If
                 Return Me._lazyAnonymousDelegateSymbol
diff --git a/src/Compilers/VisualBasic/Portable/Symbols/Source/SourceMethodSymbol.vb b/src/Compilers/VisualBasic/Portable/Symbols/Source/SourceMethodSymbol.vb
index b97582748a043652bebccee0afcef40afd274d89..6a1a6a0d13c4035da13ab7db874f8585512521a4 100644
--- a/src/Compilers/VisualBasic/Portable/Symbols/Source/SourceMethodSymbol.vb
+++ b/src/Compilers/VisualBasic/Portable/Symbols/Source/SourceMethodSymbol.vb
@@ -1296,7 +1296,7 @@ lReportErrorOnTwoTokens:
                 meParameter = Nothing
             Else
                 If _lazyMeParameter Is Nothing Then
-                    Interlocked.CompareExchange(_lazyMeParameter, New MeParameterSymbol(Me), Nothing)
+                    Interlocked.CompareExchange(Of ParameterSymbol)(_lazyMeParameter, New MeParameterSymbol(Me), Nothing)
                 End If
 
                 meParameter = _lazyMeParameter
diff --git a/src/Compilers/VisualBasic/Portable/Symbols/SynthesizedSymbols/SynthesizedMethodBase.vb b/src/Compilers/VisualBasic/Portable/Symbols/SynthesizedSymbols/SynthesizedMethodBase.vb
index cf7dfb5a7b6b28040f7076606e8f6baff7eb82f4..5613d3dca11c53797478c2ef7af773ec6abbea8c 100644
--- a/src/Compilers/VisualBasic/Portable/Symbols/SynthesizedSymbols/SynthesizedMethodBase.vb
+++ b/src/Compilers/VisualBasic/Portable/Symbols/SynthesizedSymbols/SynthesizedMethodBase.vb
@@ -178,7 +178,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Symbols
                 meParameter = Nothing
             Else
                 If _lazyMeParameter Is Nothing Then
-                    Interlocked.CompareExchange(_lazyMeParameter, New MeParameterSymbol(Me), Nothing)
+                    Interlocked.CompareExchange(Of ParameterSymbol)(_lazyMeParameter, New MeParameterSymbol(Me), Nothing)
                 End If
 
                 meParameter = _lazyMeParameter
diff --git a/src/Scripting/VisualBasicTest/BasicScriptingTest.vbproj b/src/Scripting/VisualBasicTest/BasicScriptingTest.vbproj
index a7e851f98705d8d4f7a314b6b8e0cbddd53fcb66..de98e9101948a51686290677a003ca6ec7dcf61a 100644
--- a/src/Scripting/VisualBasicTest/BasicScriptingTest.vbproj
+++ b/src/Scripting/VisualBasicTest/BasicScriptingTest.vbproj
@@ -12,7 +12,7 @@
     <TargetFramework>netstandard1.3</TargetFramework>
     <PackageTargetFallback>portable-net452</PackageTargetFallback>
     <RoslynProjectType>UnitTestDesktop</RoslynProjectType>
-    <NoWarn>$(NoWarn);40057;42016</NoWarn>
+    <NoWarn>$(NoWarn);40057</NoWarn>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Debug|AnyCPU'" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Release|AnyCPU'" />
diff --git a/src/Scripting/VisualBasicTest/InteractiveSessionTests.vb b/src/Scripting/VisualBasicTest/InteractiveSessionTests.vb
index 67e2bb07062b2fb0e21eced24538e151c9909c51..ffafd0c97a97db31d140e10fc475127bf3328e2f 100644
--- a/src/Scripting/VisualBasicTest/InteractiveSessionTests.vb
+++ b/src/Scripting/VisualBasicTest/InteractiveSessionTests.vb
@@ -19,7 +19,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Scripting.UnitTests
                 ContinueWith("Dim y As Integer = 2").
                 ContinueWith("?x + y")
 
-            Assert.Equal(3, s.ReturnValue)
+            Assert.Equal(3, CType(s.ReturnValue, Integer))
         End Function
 
         <Fact>
@@ -27,7 +27,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Scripting.UnitTests
             Dim source = "
 ?1 _
 "
-            Assert.Equal(1, VisualBasicScript.EvaluateAsync(source).Result)
+            Assert.Equal(1, CType(VisualBasicScript.EvaluateAsync(source).Result, Integer))
         End Sub
 
         <Fact>
@@ -35,7 +35,7 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Scripting.UnitTests
             Dim source = "
 ?1
 "
-            Assert.Equal(1, VisualBasicScript.EvaluateAsync(source).Result)
+            Assert.Equal(1, CType(VisualBasicScript.EvaluateAsync(source).Result, Integer))
         End Sub
 
         <Fact>
@@ -61,7 +61,7 @@ End If
 ?x + 1
 "
 
-            Assert.Equal(6, VisualBasicScript.EvaluateAsync(source).Result)
+            Assert.Equal(6, CType(VisualBasicScript.EvaluateAsync(source).Result, Integer))
         End Sub
 
         <Fact>
@@ -81,7 +81,7 @@ Dim d = New With { Key .F = 777 }
     & "" "" & (a.GetType() Is b.GetType()).ToString() _
     & "" "" & (b.GetType() is d.GetType()).ToString()
 ")
-            Assert.Equal("True False True", script.EvaluateAsync().Result)
+            Assert.Equal("True False True", CType(script.EvaluateAsync().Result, String))
         End Sub
 
         <Fact>
@@ -107,7 +107,7 @@ Dim d = Function () As Integer
     & "" "" & (b.GetType() is d.GetType()).ToString()
 ")
 
-            Assert.Equal("True False True", script.EvaluateAsync().Result)
+            Assert.Equal("True False True", CType(script.EvaluateAsync().Result, String))
         End Sub
     End Class
 
diff --git a/src/Scripting/VisualBasicTest/ScriptTests.vb b/src/Scripting/VisualBasicTest/ScriptTests.vb
index e64264a006757853a5bb74fcf08303230bb7c466..135694269fbaf4824d615fbb2d5472138c79b81b 100644
--- a/src/Scripting/VisualBasicTest/ScriptTests.vb
+++ b/src/Scripting/VisualBasicTest/ScriptTests.vb
@@ -22,14 +22,14 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Scripting.UnitTests
 
         <Fact>
         Public Sub TestEvalScript()
-            Dim value = VisualBasicScript.EvaluateAsync("? 1 + 2", s_defaultOptions)
-            Assert.Equal(3, value.Result)
+            Dim value = CType(VisualBasicScript.EvaluateAsync("? 1 + 2", s_defaultOptions).Result, Integer)
+            Assert.Equal(3, value)
         End Sub
 
         <Fact>
         Public Async Function TestRunScript() As Task
             Dim state = Await VisualBasicScript.RunAsync("? 1 + 2", s_defaultOptions)
-            Assert.Equal(3, state.ReturnValue)
+            Assert.Equal(3, CType(state.ReturnValue, Integer))
         End Function
 
         <Fact>
@@ -37,13 +37,13 @@ Namespace Microsoft.CodeAnalysis.VisualBasic.Scripting.UnitTests
             Dim script = VisualBasicScript.Create("? 1 + 2", s_defaultOptions)
             Dim state = Await script.RunAsync()
             Assert.Same(script, state.Script)
-            Assert.Equal(3, state.ReturnValue)
+            Assert.Equal(3, CType(state.ReturnValue, Integer))
         End Function
 
         <Fact>
         Public Async Function TestRunScriptWithSpecifiedReturnType() As Task
             Dim state = Await VisualBasicScript.RunAsync("? 1 + 2", s_defaultOptions)
-            Assert.Equal(3, state.ReturnValue)
+            Assert.Equal(3, CType(state.ReturnValue, Integer))
         End Function
 
         <Fact>