BUG: Visual C++ .NET Compiler Generates Two Different Native Types for the Same Boolean Return Type

Steps to Reproduce the Behavior

1. In Visual C++ .NET, create a new Managed C++ Application project that is named TestBoolean.
2. Double-click the TestBoolean.cpp file in Solution Explorer and then replace the code in that file with the following code:

   // This is the main project file for the Visual C++ Application project that is 
   // generated by using an Application Wizard.
   
   #include "stdafx.h"
   
   #using <mscorlib.dll>
   #include <tchar.h>
   
   using namespace System;
   
   __gc class TestBoolean
   {
   public:
   	[returnvalue:System::Runtime::InteropServices::MarshalAs
   	(System::Runtime::InteropServices::UnmanagedType::VariantBool)]
   	bool RetValBoolean ([System::Runtime::InteropServices::MarshalAs
   	(System::Runtime::InteropServices::UnmanagedType::VariantBool)] bool b)
   	{
   		return b;
   	}
   };
   
   int _tmain(void)
   {
   	TestBoolean *test = new TestBoolean();
   	Console::WriteLine(test->RetValBoolean(true));
   	return 0;
   }
   						

3. Press CTRL+SHIFT+B to build the project.
4. From the command prompt, type the following:

   	c:\>ildasm.exe /adv
   						

   This starts ildasm in the advanced mode.
5. Open TestBoolean.exe in ildasm.
   
   
6. On the View menu, click Metalnfo and then click Show!.
   
   Examine the metadata that is produced. You see that the compiler emits two different native types for the return value.

   Global fields
   -------------------------------------------------------
   
   Global MemberRefs
   -------------------------------------------------------
   
   TypeDef #1
   -------------------------------------------------------
   	TypDefName: TestBoolean  (02000002)
   	Flags     : [NotPublic] [AutoLayout] [Class] [AnsiClass]  (00000000)
   	Extends   : 01000008 [TypeRef] System.Object
   	Method #1 
   	-------------------------------------------------------
   		MethodName: RetValBoolean (06000003)
   		Flags     : [Public] [ReuseSlot]  (00000006)
   		RVA       : 0x00001000
   		ImplFlags : [IL] [Managed]  (00000000)
   		CallCnvntn: [DEFAULT]
   		hasThis 
   		ReturnType: Boolean
   		1 Arguments
   			Argument #1:  Boolean
   		3 Parameters
   			(0) ParamToken : (08000001) Name :  flags: [HasFieldMarshal]  (00002000)
   				NATIVE_TYPE_U1 
   			(0) ParamToken : (08000002) Name :  flags: [HasFieldMarshal]  (00002000)
   				NATIVE_TYPE_VARIANTBOOL 
   			(1) ParamToken : (08000003) Name : b flags: [HasFieldMarshal]  (00002000)
   				NATIVE_TYPE_VARIANTBOOL 
   					

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