The compilers for iOS and OSX are largely the same and if you’re consistently using the same compiler family you’re probably ok even if the version isn’t comple

The compilers for iOS and OSX are largely the same and if you’re consistently using the same compiler family you’re probably ok even if the version isn’t completely identical (major LLVM versions aren’t frequently bringing massive changes to how the optimizer is working). Additionally the UB optimization stuff you’re referencing is all within a tight margin even across families (ie GCC and clang tend to apply very similar optimizations).