Bug 185 - IsAssignableFrom is incorrect for generics based on assignable types.
Summary: IsAssignableFrom is incorrect for generics based on assignable types.
Alias: None
Product: Class Libraries
Classification: Mono
Component: System ()
Version: 2.10.x
Hardware: Macintosh Mac OS
: --- major
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2011-08-05 00:45 UTC by Sergey
Modified: 2011-08-19 18:37 UTC (History)
3 users (show)

Tags: reflection, generics, IsAssignableFrom
Is this bug a regression?: ---
Last known good build:

A test file exposing the error (272 bytes, application/octet-stream)
2011-08-05 00:45 UTC, Sergey

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Description Sergey 2011-08-05 00:45:39 UTC
Created attachment 71 [details]
A test file exposing the error

The algorithm for determining if a generic type is assignable from another type is broken in 4.0. The expression below


returns True, when it should return False.

This used to work in 2.0, 3.0, and 3.5. It also returns False in Microsoft .NET 4.0 on Windows.

Steps to reproduce:
    Compile the attached file using "dmcs Main.cs" command
    Run using "mono Main.cs" command

Expected output:

Actual output:
Comment 1 Rodrigo Kumpera 2011-08-19 18:37:28 UTC
Fixed in master/2.10 and mobile