Topic: Anyone else get this?

[TheMaster]

Code - Text: [Select]

1. Command: (setq a (cons 5020 -1))
2. (5020 . -1)
3. ; error: Exception occurred: 0xC0000005 (Access Violation)
4.  

[Kerry]

Yes
AutoCAD 2013  x64 Win 7 Pro

[TheMaster]

 

Thanks

[Jeff_M]

I, too, get this in C3D2012 x64 Win7 Pro

[TheMaster]

Thanks.

And, how about this one?

Code - C#: [Select]

1. namespace Namespace1
2. {
3.    public static class Class1
4.    {
5.       [LispFunction( "kaboom" )]
6.       public static bool Kaboom( ResultBuffer args )
7.       {
8.          if( args == null )
9.             return false;
10.          TypedValue[] array = args.AsArray();
11.          if( array.Length != 2 )
12.             return false;
13.          TypedValue a = array[0];
14.          TypedValue b = array[1];
15.          return a == b;
16.       }
17.    }
18. }

Code - Text: [Select]

1.  
2.   Command: (kaboom nil nil)
3.  
4.  

[edit]

For anyone interested, the bug is triggered by the incorrect use of object.Equals( object ) within the TypedValue's overload of the == operator. It should be using object.Equals( object, object ), rather than the instance Equals( object) method, which of course, requires a non-null instance. You might note that while the managed runtime catches most exceptions thrown by calls to a LispFunction, NullReferenceException is not one of them.

You can avoid this problem by pre-processing TypedValues that come from LISP like so:

Code - C#: [Select]

1. namespace Namespace1
2. {
3.    public static class MyExtensions
4.    {
5.        // call this in lieu of ResultBuffer.AsArray()
6.        public static TypedValue[] ToArray( this ResultBuffer args )
7.        {
8.           if( args == null )
9.              return new TypedValue[0];
10.           return args.Cast<TypedValue>()
11.              .Select( tv => object.Equals( tv.Value, null ) ? new TypedValue( tv.Value, Type.Missing ) : tv )
12.              .ToArray();
13.        }
14.    }
15. }
16.  

[Gasty]

Hi,


Tested on AutoCAD 2012 32 bits

(setq a (cons 5020 -1)) -> (5020 . -1)

(kaboom 2 3) -> nil
(kaboom 2 2) -> T
(kaboom '(1 2) '(1 2)) -> T
(kaboom '() '(1 2)) -> nil
(kaboom nil nil) -> ˇkaboom! (Fatal Error...)

Gaston Nunez

[TheMaster]

Hi,


Tested on AutoCAD 2012 32 bits

(setq a (cons 5020 -1)) -> (5020 . -1)

(kaboom 2 3) -> nil
(kaboom 2 2) -> T
(kaboom '(1 2) '(1 2)) -> T
(kaboom '() '(1 2)) -> nil
(kaboom nil nil) -> ˇkaboom! (Fatal Error...)

Gaston Nunez

Gaston - Thanks.

Sorry, I forgot to include the LISP call that triggers it (kaboom nil nil), but I see you found it

[Gasty]

Hi Tony:

It happens I'm very good crashing AutoCAD, specially with my code

Very instructive example by the way.

Gaston Nunez