So have many people. But from my experience, it is not a fun day when you find out the new compiler version you upgraded to 3 months month ago have "miscompiled

So have many people. But from my experience, it is not a fun day when you find out the new compiler version you upgraded to 3 months month ago have "miscompiled" your code for the last 2 releases of your codebase, since it contained undefined behavior which worked fine for the past 15 years when using older versions of the compiler.