Hello, is somebody out there who has consciously used the asynchronous unwind tables? The GCC documentation does not reveal much more about this feature than the mere statement of its existence. What I eventually need is the possibility to catch certain signals and unwind a part of the stack down to a certain frame in a mixed C / C++ program. A naive approach of throwing an exception from the signal handler does not work, neither does a siglongjump from the handler unwind the stack frames between it and the frame where sigsetjump was executed (although some C++ ABI drafts suggested this behaviour). The main problem is probably the kernel-generated frame of the signal handler, lying between the frame where unwinding starts and the catching frame. If I set up the signal handler to use the alternative stack, this frame won't be an obstacle any more; but I didn't find any clue how to tell the unwinding machinery (_Unwind_RaiseException and the relatives) as it is implemented in libgcc, that it has to scan over a different stack. I'd deeply appreciate any helpful advice and tips. The solution needn't be universally portable; I'll be overly glad to get it running under Linux on i386 and x86_64, and in the further future, if possible, under MacOS. Best regards, Ewgenij Gawrilow
