>> For clarification, now SIGFPE, SIGILL and SIGSEGV can't be trapped from ruby script if you have multi threads and use windows.
>> but I don't think it's big matter.
>
> Agreed--nobody seems to have noticed it but myself until now...

The point is, this issue is not mere bug. It's YARV core design issue.
As you know, ruby 1.9 can have multi threads. But many script don't
have proper multi thread safe trap code. Thus we decided always execute
trap hander by main thread. But, synchronous signal (e.g. SIGSEGV, SIGILL)
can't be delivered to other threads. It's synchronous.

Therefore, I'm planning to don't permit to use trap of synchrounous signal since
1.9.4 or later. Of course, every comments are welcome.

Thanks.