Some of this you may be able to hack around via disabling compiler optimizations. For example, -fno-strict-aliasing will disable optimizations that rely on assu

Some of this you may be able to hack around via disabling compiler optimizations. For example, -fno-strict-aliasing will disable optimizations that rely on assuming objects of different types will never alias (an assumption that gets violated by type punning). For that matter, if you're not starting on -O0, you probably should. Don't enable optimizations until it's working correctly. Of course, if the issue is that the sizes of types changed (e.g. 32 to 64 bit), no amount of flags will fix that automatically for you. Though you could still install a 32 bit compiler on a modern distro.