[nem-bug] [Nemerle 0001018]: nonpublic virtual method in generic class

[feedback at nemerle.org]

The following issue has been CONFIRMED.
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<http://nemerle.org/bugs/view.php?id=1018> 
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Reported By:                divan
Assigned To:                
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Project:                    Nemerle
Issue ID:                   1018
Category:                   Compiler (blocked by framework)
Reproducibility:            always
Severity:                   major
Priority:                   normal
Status:                     confirmed
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Date Submitted:             05-19-2007 14:26 CEST
Last Modified:              05-20-2007 16:31 CEST
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Summary:                    nonpublic virtual method in generic class
Description: 
If nonpublic virtual method is declared in generic base then it's override
produces bad IL (at least PEVerify says that).


C# adds 'newslot' to those methods attributes, maybe it's the key, or at
least a workaround.
Ncc doesn't generate newslot for public too and it's ok, so it can be a
bug in PEVerify.
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----------------------------------------------------------------------
 divan - 05-19-07 14:56 
----------------------------------------------------------------------
The same with nonpublic implementation of generic interfaces.

public interface B [T]{
  f () : object
}
public class A : B [object] {
  protected f () : object implements B[object].f { null; }
}
_ = (A () : B[object]).f ();
()

And even with public when implements is used
public interface B [T]{
  f () : object
}
public class A : B [object] {
  public ff () : object implements B[object].f { null; }
}
_ = (A () : B[object]).f ();
()

Both cases: PEVerify: [token  0x02000003] Type load failed.
[IL]: Error: [C:\nemerle_svn\bin\Debug\out.exe : bug::Main][offset
0x000000
00] Unable to resolve token.
2 Errors Verifying out.exe

----------------------------------------------------------------------
 nazgul - 05-19-07 17:10 
----------------------------------------------------------------------
This is the problem of .NET bug in Reflection.Emit API

----------------------------------------------------------------------
 divan - 05-20-07 13:52 
----------------------------------------------------------------------
Hacky workaround is to write:
public class B [T] {
    internal virtual f () : T { null :> T } 
}
public class A : B [object] {
    internal virtual f () : object { null; } // W: use 'new' or
'override'
}
()

----------------------------------------------------------------------
 divan - 05-20-07 16:31 
----------------------------------------------------------------------
Another workaround is to use mono to compile such cases :)

Issue History
Date Modified  Username       Field                    Change              
======================================================================
05-19-07 14:26 divan          New Issue                                    
05-19-07 14:56 divan          Note Added: 0001897                          
05-19-07 17:10 nazgul         Note Added: 0001898                          
05-20-07 13:52 divan          Note Added: 0001899                          
05-20-07 16:31 divan          Note Added: 0001900                          
05-20-07 16:31 divan          Status                   new => confirmed    
05-20-07 16:31 divan          Category                 Compiler => Compiler
(blocked by framework)
05-20-07 16:31 divan          Description Updated                          
05-20-07 16:31 divan          Additional Information Updated                    
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