[Mono-list] NullRefException compiling with mcs

Stuart Ballard sballard@netreach.com
Fri, 30 Jan 2004 09:09:37 -0500

Miguel de Icaza wrote:
> I see where the program is crashing, but am still going to need you to
> put prints around that area, so we understand what is happening and what
> is going wrong.

Can you suggest some things that I should print that will help me to 
determine what types are being compiled that result in the crash? I'm 
afraid that the code in interface.cs is somewhat over my head - in 
particular, I have no idea what the role of a TypeBuilder is, which is 
presumably fairly fundamental to diagnosing this problem.

My first attempt at isolating a testcase failed, but in a possibly 
interesting way. Am I right that interface.cs suggests that the problem 
has something to do with an interface (as opposed to a class or some 
other kind of Type)? There's only one interface declared in the whole of 
my project (although I do use and implement various interfaces that are 
declared in referenced DLLs), so I though "okay, easy starting point: if 
I compile the smallest possible set of files that includes that 
interface declaration, I should get the error". Turns out I don't - it 
builds fine.

> You should use this information to produce a small test sample.  It is
> probably something related to recursive definitions of the types, but I
> need the small test case.

I'll keep trying, but if you can suggest some things that I should print 
out that will help me identify which types are in play at the time the 
error occurs, it will speed me up significantly.

Thanks for all your help so far,

Stuart Ballard, Senior Web Developer
NetReach, Inc.
(215) 283-2300, ext. 126