+Of course, to explain *why* the abstract machine is defined the way it is, we have to look at optimizations and hardware-level concerns.
+But without an abstract machine, it is very hard to ensure that all the optimizations a compiler performs are consistent---in fact, both [LLVM](https://bugs.llvm.org/show_bug.cgi?id=35229) and [GCC](https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65752) suffer from miscompilations caused by combining optimizations that all seem fine in isolation, but together cause incorrect code generation.
+The abstract machine is needed as an ultimate arbiter that shows if all of the optimizations are correct, or if some of them are in conflict with each other.
+I also think that when writing unsafe code, it is much easier to keep in your head a fixed abstract machine as opposed to a set of optimizations that might change any time, and might or might not be applied in any order.
+