I understand compiler optimizations having unintended consequences, e.g. https://godbolt.org/z/r39jK1ddv https://godbolt.org/z/r39jK1ddv but there are a lot of

I understand compiler optimizations having unintended consequences, e.g. https://godbolt.org/z/r39jK1ddv https://godbolt.org/z/r39jK1ddv but there are a lot of options he may use to enable or disable optimizations (assuming GCC here): https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html https://gcc.gnu.org/onlinedocs/gcc/Optimize-Options.html This is even more difficult to do with higher-level languages.