Fix sanitize-undefined config check. Don't ALLOW_UNALIGNED when checking.

The -fsanitize=undefined check need to use AC_LINK_IFELSE to make sure
libubsan is installed. When doing undefined checking we should disable
ALLOW_UNALIGNED memory accesses to catch issues where we do unaligned
accesses by accident.

Signed-off-by: Mark Wielaard <mjw@redhat.com>
4 files changed