[iOS] Random crashing due to apparent race condition

[ndermg]

I have an app which calls ping.start quite frequently. Leave it running long enough and it will eventually crash due to hitting the assert(NO) on line 526 of GBPing.m where it does a switch on the value of self.hostAddressFamily. Occasionally, the value is 0 (and this can also be induced manually by setting a breakpoint on line 516).
Is there any reason why that default cannot be removed? When I comment it out, nothing seems to explode and the crash doesn't occur anymore.

(I did notice this other, non-React Native GBPing does this instead of assert(NO):

                err = errno;
                return;

However, when I try changing it to that, we soon crash due to another race condition: the reject callback in the 'start' method in RNReactNativePing.m gets called twice, once in the fail block (line 57) then again in the dispatch_after block (line 61) which causes a fatal 'Illegal callback invocation from native module' error.)