swab: Correctly treat the data as misaligned

The __aligned attribute in the previous version applied to the location
of the pointers, not the data the pointers pointed to.  While this
could be fixed by applying the attribute to a local typedef of uint16_t,
just using memcpy() for the unaligned access is simpler and ISO C.

This fixes the build on CHERI architectures which do not support
misaligned pointers and were thus failing with:

lib/libc/string/swab.c:12:18: error: alignment (1) of 'const uint16_t *' (aka 'const unsigned short *') is less than the required capability alignment (16) [-Werror,-Wcheri-capability-misuse]
   12 |         const uint16_t *f __aligned(1) = from;
      |

Co-authored by:	Jessica Clarke <jrtc27@FreeBSD.org>
Fixes:		02ebbc781f08 ("swab: Fix implementation to support overlapping copies")
Sponsored by:	AFRL, DARPA

Reviewed by:	markj
Differential Revision:	https://reviews.freebsd.org/D54399

0 files changed, 0 insertions, 0 deletions