Spec#, nullables and more

[Walter Bright]

FeepingCreature wrote:
> Walter Bright Wrote:
> 
>> FeepingCreature wrote:
>>> Walter Bright Wrote:
>>>> All that does is reinvent the null pointer seg fault. The hardware does
>>>>  this for you for free.
>>> Walter, I know you're a Windows programmer but this cannot be the first
>>> time somebody has told you this - YOU CANNOT RECOVER FROM SEG FAULTS
>>> UNDER LINUX.
>>> 
>>> Access violations are not a cross-platform substitute for exceptions.
>> Why would you want to recover from a seg fault?
>> 
>> (asserts in D are not recoverable exceptions)
> 
> You cannot do a lot of things from a signal handler. You can't sjlj, which
> means sjlj exception handling is out (as are, in fact, most methods of
> exception handling). This means stack traces are out unless you have special
> handling for segfaults that decodes the stack and prints the error pos. That
> in turn means you need to have a debugger attached to get stacktraces, which
> can be annoying especially in long-running programs where the crash is often
> the first indication you have of a problem.
> 
> Furthermore, scope guards will not be run. You can't run the GC from a signal
> handler because it requires pthreads which is not safe for signal handlers.
> Garbage collected classes will not be freed. Static class destructors cannot
> be run. Module destructures can not be safely executed.

Sure. That's why assert errors are not recoverable.