On Wed, 21 Aug 2019, Paul Koning wrote:
> I agree, but if the new approach generates a warning for code that was written
> to the old rules, that would be unfortunate.
FWIW I don't know which GCC versions accepted 'packed' on a scalar type.
Already in 2006 GCC 3.4 would issue a warning:
$ echo 'typedef int ui __attribute__((packed));' | gcc34 -xc - -S -o-
.file ""
<stdin>:1: warning: `packed' attribute ignored
.section .note.GNU-stack,"",@progbits
.ident "GCC: (GNU) 3.4.6 20060404 (Red Hat 3.4.6-4)"
> Yes. But last I tried, optimizing that for > 1 alignment is problematic
> because that information often doesn't make it down to the target code even
> though it is documented to do so.
Thanks, indeed this memcpy solution is not so well suited for that.
Alexander
