---- Reported by stephen@covidimus.net 2005-07-30 12:12:48 MST ----

Description of Problem:

Gmcs appears to recognize and accept a class constraint (where T:class) on
a generic method, but the 'as' operator doesn't work as it should when the
class constraint is applied.

Code to Reproduce the Problem:

 public static T QueryInterface<T>(object val)
   where T : class
 {
     if (val == null)
         return null;

     // First, see if the given object can be directly cast
     // to the requested type.  This will be a common case,
     // especially when checking for standard behavior interface
     // implementations (like IXrcDataElement).
     T tval = val as T;
     if (tval != null)
         return tval;

     // ... rest of method unimportant and omitted ...
     return null;
 }



Actual Results:

Xircle.Core/src/Core/XrcConvert.cs(118) error CS0077: The as operator
should be used with a reference type only (T is a value type)

Expected Results:

The 'as' operator should compile without errors b/c the 'class' constraint
(where T:class) on the method should cause T to be assumed to be a
reference type.  Visual Studio beta 2 accepts this code without error.

How often does this happen? 

Every time.

Additional Information:

https://bugzilla.novell.com/show_bug.cgi?id=MONO75368 appeared to me to be related, but even though it's marked as
fixed, the problem still appears in SVN head, so perhaps it is not.



---- Additional Comments From atsushi@ximian.com 2005-09-05 02:59:02 MST ----

Created an attachment (id=168283)
proposed fix




---- Additional Comments From martin@ximian.com 2005-09-05 13:41:46 MST ----

Fixed in SVN (the patch is a big no-go, used a different one).



---- Additional Comments From miguel@ximian.com 2005-09-05 15:09:17 MST ----

can we get a test case for this, to integrate into the build?



---- Additional Comments From atsushi@ximian.com 2005-09-05 15:29:50 MST ----

added gtest-200.cs (r49503).

Imported an attachment (id=168283)

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