I maintain embedded development C and C++ toolchains for a living. I have seen my share of compiler bugs. For example, some optimization pass in a popular open-

I maintain embedded development C and C++ toolchains for a living. I have seen my share of compiler bugs. For example, some optimization pass in a popular open-source compiler that would lose track of dereferences of pointer variables if they were more than 12 bytes deep in the stack, meaning that a reference capture in a C++ lambda would get converted to a value capture if it was the third or later capture in order and changes to the referenced capture would be lost.... Anyway, my experience is that compiler bugs do exist, but maybe 99% or so of "compiler bugs" reported by my users turn out to be undefined behaviour in their code.