[Mono-dev] UnmanagedFunctionPointer/Callingconvention Bug

[David_Hudson at capgroup.com]

Hi,

I found a bug using Mono 1.13.8 on Windows XP using gmcs.

I have posted this as Bug 78982 in Bugzilla.

This code will not compile:

----------------------------------------
using System;
using System.Runtime.InteropServices;

namespace Test.Bug
{
    public sealed class Test
    {
        private const CallingConvention CALLING_CONVENTION =
CallingConvention.Cdecl;

        [UnmanagedFunctionPointer(CALLING_CONVENTION)]
        public delegate int CallingConventionBug(IntPtr ptr);
    }
}
----------------------------------------

You get this set of compilation errors.
------------------------------
[csc] Unhandled Exception: System.NullReferenceException: Object reference
not set to an instance of an object
                  [csc] in <0x00010>
Mono.CSharp.TypeManager:IsPrivateAccessible (System.Type type, System.Type
parent)
                  [csc] in <0x002d0> Mono.CSharp.TypeManager+Closure:Filter
(System.Reflection.MemberInfo m, System.Object filter_criteria)
                  [csc] in (wrapper delegate-invoke)
System.MulticastDelegate:invoke_bool_MemberInfo_object
(System.Reflection.MemberInfo,object)
                  [csc] in <0x001e5> Mono.CSharp.MemberCache:FindMembers
(MemberTypes mt, BindingFlags bf, System.String name,
System.Reflection.MemberFilter filter, System.Object criteria)
                  [csc] in <0x000be>
Mono.CSharp.TypeManager:MemberLookup_FindMembers (System.Type t,
MemberTypes mt, BindingFlags bf, System.String name, System.Boolean
used_cache)
                  [csc] in <0x001ad>
Mono.CSharp.TypeManager:RealMemberLookup (System.Type invocation_type,
System.Type qualifier_type, System.Type queried_type, MemberTypes mt,
BindingFlags original_bf, System.String name, IList almost_match)
                  [csc] in <0x0001f> Mono.CSharp.TypeManager:MemberLookup
(System.Type invocation_type, System.Type qualifier_type, System.Type
queried_type, MemberTypes mt, BindingFlags original_bf, System.String name,
IList almost_match)
                  [csc] in <0x00038> Mono.CSharp.Expression:MemberLookup
(Mono.CSharp.EmitContext ec, System.Type container_type, System.Type
qualifier_type, System.Type queried_type, System.String name, MemberTypes
mt, BindingFlags bf, Location loc)
                  [csc] in <0x00022> Mono.CSharp.Expression:MemberLookup
(Mono.CSharp.EmitContext ec, System.Type queried_type, System.String name,
Location loc)
                  [csc] in <0x001b0>
Mono.CSharp.SimpleName:DoSimpleNameResolve (Mono.CSharp.EmitContext ec,
Mono.CSharp.Expression right_side, Boolean intermediate)
                  [csc] in <0x00030>
Mono.CSharp.SimpleName:SimpleNameResolve (Mono.CSharp.EmitContext ec,
Mono.CSharp.Expression right_side, Boolean intermediate)
                  [csc] in <0x00014> Mono.CSharp.SimpleName:DoResolve
(Mono.CSharp.EmitContext ec, Boolean intermediate)
                  [csc] in <0x000d2> Mono.CSharp.Expression:Resolve
(Mono.CSharp.EmitContext ec, ResolveFlags flags)
                  [csc] in <0x00012> Mono.CSharp.Expression:Resolve
(Mono.CSharp.EmitContext ec)
                  [csc] in <0x0014d> Mono.CSharp.Argument:Resolve
(Mono.CSharp.EmitContext ec, Location loc)
                  [csc] in <0x00275> Mono.CSharp.Attribute:ResolveArguments
(Mono.CSharp.EmitContext ec)
                  [csc] in <0x0015b> Mono.CSharp.Attribute:Resolve
(Mono.CSharp.EmitContext ec)
                  [csc] in <0x00064> Mono.CSharp.Attribute:Emit
(Mono.CSharp.EmitContext ec, Mono.CSharp.Attributable ias,
System.Collections.Specialized.ListDictionary emitted_attr)
                  [csc] in <0x0009c> Mono.CSharp.Attributes:Emit
(Mono.CSharp.EmitContext ec, Mono.CSharp.Attributable ias)
                  [csc] in <0x0003d> Mono.CSharp.Delegate:Emit ()
                  [csc] in <0x00ecd> Mono.CSharp.TypeContainer:EmitType ()
                  [csc] in <0x00226> Mono.CSharp.RootContext:EmitCode ()
                  [csc] in <0x00a9f> Mono.CSharp.Driver:MainDriver
(System.String[] args)
                  [csc] in <0x00051> Mono.CSharp.Driver:Main
(System.String[] args)
--------------------------------
-- However, if you mark the const CallingConvention as public, the code
compiles fine.

using System;
using System.Runtime.InteropServices;

namespace Test.Bug
{
    public sealed class Test
    {
        public const CallingConvention CALLING_CONVENTION =
CallingConvention.Cdecl;

        [UnmanagedFunctionPointer(CALLING_CONVENTION)]
        public delegate int CallingConventionBug(IntPtr ptr);
    }

-- Or if you explicitly put the callingConvention in the attribute, the
code compiles fine.

using System;
using System.Runtime.InteropServices;

namespace Test.Bug
{
    public sealed class Test
    {
        //private const CallingConvention CALLING_CONVENTION =
CallingConvention.Cdecl;

        [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
        public delegate int CallingConventionBug(IntPtr ptr);
    }
}


}

Thanks
Dave