Well you can easily detect trivial examples like "while(1)" and "for(i=0;true;i++)". But otherwise how would know some is an infinite loop?
Put a bit more simply, to work out if a problem is unsolvable (infinitly looping) you need to evaluate the problem... By trying to solve it. Checkout the halting problem for more details.
Put a bit more simply, to work out if a problem is unsolvable (infinitly looping) you need to evaluate the problem... By trying to solve it. Checkout the halting problem for more details.
https://en.m.wikipedia.org/wiki/Halting_problem