Except multi-thread programming, I didn't find any compiler's optimizer related bugs. The truth is, most heisenbugs I found are somewhat related to memory acces

Except multi-thread programming, I didn't find any compiler's optimizer related bugs. The truth is, most heisenbugs I found are somewhat related to memory access. It is just too risky to assume it is a compiler bug. I always think in the other way: unless you can prove (by generating assembly code and a possible scenario), the bug is in your code.