> Many programs rely on misaligned access, and features like pragma packed do too. I doubt they’ll be able to break all of that legacy code. It's already broke

> Many programs rely on misaligned access, and features like pragma packed do too. I doubt they’ll be able to break all of that legacy code. It's already broken. You're just not seeing it on x86. (Not sure how tolerant ARM is.) I work in network software engineering, i.e. PowerPC used to be a common architecture. Those never accepted misaligned pointers (albeit you could of course trap the misalignment exception and emulate the access, or print a backtrace to identify the location.) Really this is a problem caused by the "common case" (x86) being permissive in what it accepts, creating fallout further down the line if you ever need the code to run on something less permissive. [Edit: actually, oops, it's not PowerPC; those are relatively permissive too. Pretty sure DEC Alpha and m68k are restrictive.]