[konstmonst]

"If a particular compiler specified that casting pointers of wrong alignments causes a segfault" Sure it does. It says using undefined behaviour can cause daemons fly out of your nose, among other things (including but not limited to segfaulting).

[Sagiri]

If the semantics of casting pointers of wrong alignments were defined to be demons flying out of your nose, it would be perfectly acceptable to rely on that behavior.