On Thursday, 3 October 2013 at 00:25:26 UTC, Walter Bright wrote:
Although I haven't seen the system you describe, I'm very skeptical that it found the solution to the problem of a program successfully continuing after it has crashed due to program bugs. I remain firmly convinced that that is an utterly wrong and doomed approach to the problem of reliability.
Segfaults aren't necessarily bugs... though I'm not sure if a userspace handler can do much about it. But from a kernel perspective, they can be generated by page faults too, which can be successfully handled by loading the requested memory block (e.g. from a swap file) and then retrying the operation, or copying the page into a writable location and mapping that in; hardware assisted copy-on-write.
I've never tried to do this in a unix program so I don't know how much you can do, but presumably Sean's example did something along these lines, so it would be by design rather than bugs.
