RE: [PATCH v2] x86/insn, tools/x86: Fix some potential undefined behavior.

[David Laight]

From: hpa@xxxxxxxxx
> Sent: 15 October 2020 22:35
> >Don't perform unaligned loads in __get_next and __peek_nbyte_next as
> >these are forms of undefined behavior.
...
> > #define __get_next(t, insn)	\
> >-	({ t r = *(t*)insn->next_byte; insn->next_byte += sizeof(t); r; })
> >+	({ t r; memcpy(&r, insn->next_byte, sizeof(t)); insn->next_byte += sizeof(t); r; })

Interesting other idea.
Can you add an 'aligned(1)' into the '*(t *)' cast?
I think '*(t aligned(1) *)' is the right cast.
(gcc seems to accept it either size of the type.)

	David

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