Bug 40493 - Invalid IL when using ?. operator on a Func<T> parameter in a generic function when T is unconstrained
Summary: Invalid IL when using ?. operator on a Func<T> parameter in a generic functi...
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: 4.2.0 (C6)
Hardware: PC Linux
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2016-04-18 19:56 UTC by Michał Przybyś
Modified: 2016-04-20 12:33 UTC (History)
1 user (show)

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

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Description Michał Przybyś 2016-04-18 19:56:13 UTC
The following code is compiled by mcs and throws an InvalidProgramException when run:

using System;

static class Program
    static void Bug<T>(Func<T> func)
    static void Main()
        Bug(() => 123);

csc from VS2015 on the other hand returns error "CS0023: Operator '?' cannot be applied to operand of type 'T'" unless there is a constraint on T.

Reproduced both on Ubuntu with mono and FreeBSD with mono
Comment 1 Marek Safar 2016-04-20 12:33:33 UTC
Fixed in master and 4.5 preview