Bug 23433 - Activator.CreateInstance Method (Type, Object[]) is broken on mono
Summary: Activator.CreateInstance Method (Type, Object[]) is broken on mono
Alias: None
Product: Class Libraries
Classification: Mono
Component: mscorlib ()
Version: unspecified
Hardware: PC All
: --- normal
Target Milestone: Untriaged
Assignee: Marek Safar
Depends on:
Reported: 2014-09-27 09:28 UTC by Mike
Modified: 2015-02-27 06:07 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

C# source reproducing the issue (292 bytes, application/octet-stream)
2014-09-27 09:28 UTC, Mike

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Description Mike 2014-09-27 09:28:42 UTC
Created attachment 8216 [details]
C# source reproducing the issue

using System;
namespace ParamsConstructor
	class TestClass{
		public TestClass(params object[] parameters)
	class MainClass
		public static void Main (string[] args)
			var temp=Activator.CreateInstance(typeof(TestClass),1,2,3,4,5);
			GC.KeepAlive (temp);

This tiny program is working on .Net 4.5 without any problems - but it fails when executed on mono with the following exception:

[ERROR] FATAL UNHANDLED EXCEPTION: System.MissingMethodException: No constructor found for ParamsConstructor.TestClass::.ctor(System.Int32, System.Int32, System.Int32, System.Int32, System.Int32)
  at System.Activator.CreateInstance (System.Type type, BindingFlags bindingAttr, System.Reflection.Binder binder, System.Object[] args, System.Globalization.CultureInfo culture, System.Object[] activationAttributes) [0x00180] in /private/tmp/source-mono-mac-3.10.0-branch/bockbuild-mono-3.10.0-branch/profiles/mono-mac-xamarin/build-root/mono-3.10.0/mcs/class/corlib/System/Activator.cs:301 
  at System.Activator.CreateInstance (System.Type type, System.Object[] args, System.Object[] activationAttributes) [0x00000] in /private/tmp/source-mono-mac-3.10.0-branch/bockbuild-mono-3.10.0-branch/profiles/mono-mac-xamarin/build-root/mono-3.10.0/mcs/class/corlib/System/Activator.cs:232 
  at System.Activator.CreateInstance (System.Type type, System.Object[] args) [0x00000] in /private/tmp/source-mono-mac-3.10.0-branch/bockbuild-mono-3.10.0-branch/profiles/mono-mac-xamarin/build-root/mono-3.10.0/mcs/class/corlib/System/Activator.cs:227 
  at ParamsConstructor.MainClass.Main (System.String[] args) [0x00001] in /Users/user/repo/ParamsConstructor/Program.cs:15 

Mono JIT compiler version 3.10.0 ((detached/ac51002 Wed Sep 17 18:34:00 EDT
Copyright (C) 2002-2014 Novell, Inc, Xamarin Inc and Contributors.
    TLS:           normal
    SIGSEGV:       altstack
    Notification:  kqueue
    Architecture:  x86
    Disabled:      none
    Misc:          softdebug 
    LLVM:          yes(3.4svn-mono-(detached/e656cac)
    GC:            sgen

Mono C# compiler version

The same issue applies to linux installations.
Comment 1 Marek Safar 2015-02-27 06:07:18 UTC
Fixed in master