signal_set goes into an infinit handling loop while handling SEGV

[Pichot Fabien <pichot.fabien@…>]

When you create a signal_set handling SIGSEGV, and generate a real SEGV just after a call to async_wait, the program goes into an infinite loop of handling, burning a cpu to 100%.

It seems that the asio handler writes the signal number into a pipe, returns, and is called again indefinitely (Cf the {l,s}trace log).

I attached a small test to reproduce the problem, strace and ltrace files (interrupted after few seconds). Not sure if it's useful though

[Pichot Fabien <pichot.fabien@…>]

test emphazing the problem

[Pichot Fabien <pichot.fabien@…>]

ltrace log

[Pichot Fabien <pichot.fabien@…>]

strace log

[chris_kohlhoff]

According to POSIX, the allowing the C signal handler to return after handling one of SIGFPE, SIGILL, or SIGSEGV results in undefined behaviour. Don't use them with signal_set.