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by gritzko 30 days ago
That better be marked "historical". At least, Lemire says:

On recent Intel and 64-bit ARM processors, data alignment does not make processing a lot faster. It is a micro-optimization. Data alignment for speed is a myth. // https://lemire.me/blog/2012/05/31/data-alignment-for-speed-m...

(while in the olden days, a program may crash on unaligned access, esp on RISC)

1 comments

Don't mix up what processors do with what the C standard allows you to get away with.
...and don't mix up the C standard with what actually existing compilers allow you to get away with ;) In the end the standard is merely a set of guidelines. What matters is how compiler toolchains behave in the real word, and breaking code which does unaligned memory accesses by 'UB exploitation' would be quite insane.
Sanity ain't a hard requirement for C compilers.