Bug 11241 - Erroneous CS0030 error when referencing class in another assembly
Summary: Erroneous CS0030 error when referencing class in another assembly
Alias: None
Product: Compilers
Classification: Mono
Component: C# ()
Version: unspecified
Hardware: Macintosh Mac OS
: --- normal
Target Milestone: ---
Assignee: Marek Safar
Depends on:
Reported: 2013-03-18 18:06 UTC by Martin Potter
Modified: 2013-04-08 10:47 UTC (History)
2 users (show)

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

Classes to compile as a library (1.20 KB, application/octet-stream)
2013-03-18 18:06 UTC, Martin Potter
Program that references external library (160 bytes, application/octet-stream)
2013-03-18 18:08 UTC, Martin Potter

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Description Martin Potter 2013-03-18 18:06:11 UTC
Created attachment 3644 [details]
Classes to compile as a library

The compiler reports CS0030 when casting a class to an interface declared on the base class, but only if the class is in a referenced assembly; if the class is compiled as part of the assembly where the cast occurs, compilation will succeed. This is a new error since 3.0.2. To reproduce:

1. Compile the attached file, ExternalLib.cs, as a library
2. Compile an program that references the library from step 1 with the line (IEquatable<Foo>) new Baz();
3. The compiler reports CS0030 when it should not.
Comment 1 Martin Potter 2013-03-18 18:08:27 UTC
Created attachment 3645 [details]
Program that references external library
Comment 2 Martin Potter 2013-03-18 18:09:34 UTC
Running the following results in CS0030:

mcs Bug11241.cs /r:ExternalLib.dll /out:Bug11241.exe

Running the following succeeds:

mcs Bug11241.cs ExternalLib.cs /out:Bug11241.exe
Comment 3 Marek Safar 2013-03-19 13:29:11 UTC
Fixed in master