You are right in that the return is wrong and accidentally stayed in during example reduction down to a smaller version. Without it, the result is still the same.

The reason I was testing this was a discussion on IRC about functions decaying to pointer to functions, such that they are endlessly dereferenceable. The snippet above crashes GCC -- hard.

So, while the implementation is free not to handle 10^7 dereferencing operations, I'm not sure a hard crash is the right answer.

Here's a version without the return and using a lambda to shorten it further:

    python -S -c 'print("int main(){(" + "*"*10**7 + "+[]{})();}")' | g++ -std=c++11 -xc++ -