Bug 49419 - Generics, Inheritance, Using, InnerClass => NullPointerException
Summary: Generics, Inheritance, Using, InnerClass => NullPointerException
Status: NEW
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: 4.8.0 (C9)
Hardware: PC Linux
: --- normal
Target Milestone: ---
Assignee: Marek Safar
: 52759 ()
Depends on:
Reported: 2016-12-09 05:08 UTC by Widagdo Setiawan
Modified: 2017-02-27 14:59 UTC (History)
2 users (show)

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

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Description Widagdo Setiawan 2016-12-09 05:08:56 UTC
Mono JIT compiler version 4.8.0 (Stable
Linux Kernel 3.10.0-327.36.3.el7.x86_64
OS: Centos 7

The sample code below compiles just fine under Visual Studio 15 on Windows 10.
However, the mono compiler throws NullReferenceException.

From my experiments, the sample code below is the simplest required to reproduce the bug.

using TypedGenericClass = MonoBugReport.GenericClass<MonoBugReport.DerivedClass.CustomType>;

namespace MonoBugReport
    class GenericClass<T>

    class DerivedClass : TypedGenericClass
        public class CustomType
Comment 1 Marek Safar 2017-02-27 14:59:55 UTC
*** Bug 52759 has been marked as a duplicate of this bug. ***