Am 24.08.2010 19:46, schrieb Adam Barth:
One thing Darin and I discussed at WWDC (yes, this email has been a long time coming) is better programming patterns to prevent memory leaks. As I'm sure you know, whenever you allocate a RefCounted object, you need to call adoptRef to prevent a memory leak by adopting the object's initial reference:adoptRef(new FancyRefCountedObject()) We now have an ASSERT that enforces this programming pattern, so we should be able to catch errors pretty easily. Recently, Darin also introduced an analogous function for OwnPtr: adoptPtr(new NiftyNonRefCountedObject()) What adoptPtr does is shove the newly allocated object into a PassOwnPtr, which together with OwnPtr, makes sure we don't leak the object. By using one of these two functions every time we call new, it's easy to see that we don't have any memory leaks. In the cases where we have an intentional memory leak (e.g., for a static), please use the leakPtr() member function to document the leak. In writing new code, please avoid using "naked" calls to new. If you're making an object that you expect to be heap-allocated, please add a "create" method, similar to the create method we use for RefCounted objects: static PassOwnPtr<NiftyNonRefCountedObject> create(ParamClass* param) { return adoptPtr(new NiftyNonRefCountedObject(param)); } You should also make the constructor non-public so folks are forced to call the create method. (Of course, stack-allocated objects should have public constructors.) I'm going through WebCore and removing as many naked news and I can. At some point, we'll add a stylebot rule to flag violations for new code. If you'd like to help out, pick a directory and change all the calls to new to use adoptRef or adoptPtr, as appropriate.
this reminds me that I've always been wondering about checks for allocation failure in WebCore (versus concerns about leaks). A plain call to new may throw an std::bad_alloc exception. If this is not considered, it may leave objects in an invalid state, even when using objects such as RefPtr to wrap arround allocations. I don't remember any specific place in the WebCore code where it would be a problem, I just don't remember seeing any code that deals with allocation failures. Is this a design choice somehow? If so, is there some online documentation/discussion about it? (Tried to google it but found nothing...)
Best regards, -Stephan _______________________________________________ webkit-dev mailing list webkit-dev@lists.webkit.org http://lists.webkit.org/mailman/listinfo.cgi/webkit-dev
