[cffi-devel] Interface problem in LispWorks but not in SBCL

[Martin Simmons]

>>>>> On Mon, 21 Nov 2011 10:28:56 +0100, Sascha Van Cauwelaert said:
> 
> Hello everybody,
> 
> I am using SWIG to generate CFFI code to be used into LispWorks 6. The
> interface is between C++ and Common Lisp. Then, I try to call that function
> from LispWorks :
> 
> std::string  test() {
> 	freopen ("/tmp/mystdout.txt","w",stdout);
> 	freopen ("/tmp/mystderr.txt","w",stderr);
> 	std::cout << "Redirected stdout." << std::endl;
> 	std::cerr << "Redirected stderr." << std::endl;
> 	
> 	GRelation testgr(3);
> 
> 	std::cout << "test ! " << std::endl;
> 	std::cerr << "test cerr! " << std::endl;
> 	std::cout << testgr.arity() << std::endl;
> 	std::cerr << testgr.arity() << std::endl;	
> 	std::cout << "test after! " << std::endl;
> 	std::cerr << "test cerr after! " << std::endl;
> 	std::stringstream os;
> 	os << testgr << std::endl ;
> 	return os.str();
> }
> 
> As you can see, I just create one object and print lots of stuff, including
> an object attribute. Everything I print before trying to print the attribute
> prints ok in the redirected outputs. The attribute is not printed and
> nothing else afterwards. I also get the following error when I add testgr to
> the stringstream os :
> 
> lispworks-personal-6-0-1-macos-universal(52881,0xb0314000) malloc: *** error for object 0x17be20f8: pointer being freed was not allocated
> 
> This is what happen in LispWorks. If I compile directly in C++, no
> problem. If I use SBCL (other Common Lisp implementation) instead of
> LispWorks, everything works correctly ! The problem is that I have to use
> LispWorks ...
> 
> Does anybody has had a similar problem ? I guess I am not the only one who
> tried to call some C++ from LispWorks. Any clue is very welcome. I think
> maybe the problem can be linked to the garbage collection from LispWorks but
> I don't know much about this.
> 
> I thank you in advance for your help, I am really stuck here. 

I don't see how garbage collection can cause it, because malloc is not
affected by the LispWorks GC (unless something is doing bad things with
finalization routines).

-- 
Martin Simmons
LispWorks Ltd
http://www.lispworks.com/