Hi Dominic!

On Fri, 13 Jan 2006 00:29:08 +0000, "lisp" lisp@spikeisland.com wrote:

I've tracked down what looks to be a bug in the mechanism for releasing delegate adapters.

The foreign callable ReleaseDelegateAdapter is declared with a return type of ffi-void-pointer but tries to return the result of remhash - a boolean. On LWW (at least) this results in:

Condition: T cannot be converted to foreign type :POINTER. Call to SYSTEM::FOREIGN-CALLABLE-ENTRY-POINT-NEW-PROCESS-AUX (offset 21) SYSTEM::FUNC : RDNZL::%FOREIGN-CALLABLE/RELEASEDELEGATEADAPTER

I would suggest changing it (and the corresponding initialisation and DLL code) to have a void return type:

(ffi-define-callable (ReleaseDelegateAdapter ffi-void) ((index ffi-integer)) ;; remove entry from hash table if CLR is done with it (remhash index *callback-hash*))

Also, in DelegateAdapter.cpp you have a comment on the destructor that it doesn't appear to be working:

// the destructor notifies Lisp that this instance is no longer used - // at least in theory, this doesn't seem to work right now DelegateAdapter::~DelegateAdapter() { release(indexIntoLisp); }

This may have beeen the caused by the callback/threading issues discussed recently. At least it has certainly worked for me here (hence this bug report) when using a DLL based LWW image (many thanks for your recent example of this). Perhaps the .NET GC is running in a different thread, so the callback was failing in a normal .EXE image?

Makes perfect sense to me. I've updated both the Lisp and the C++ code according to your recommendations - see ChangeLogs below.

However, I'm a bit in a hurry and I couldn't figure out an easy example which shows that ReleaseDelegateAdapter is actually called - at least not from a DLL-based LWW image. Could you please check if it works and report back to the list if possible?

Thanks a lot, Edi.

Lisp code: ----------

Version 0.8.0 2006-01-13 Fix mechanism which releases delegate adapters (thanks to Dominic Robinson) Updated to DLL version 0.5.0

http://weitz.de/files/RDNZL.tar.gz

C++ code (optional): --------------------

Version 0.5.0 2006-01-13 Fix mechanism which releases delegate adapters (thanks to Dominic Robinson)

http://weitz.de/files/RDNZL_cpp.tar.gz