Serious compatibility breakage in -current.

[Carl Shapiro]

On Nov 29, 2007 3:28 AM, Kostik Belousov <kostikbel at gmail.com> wrote:
> Please, try the patch below and report whether it is enough to fix cmucl
> and any other regressions.

With this patch applied old and new binaries are delivered a SIGBUS
instead of SIGSEGV and the si_code is always BUS_ADRERR.  This is
halfway between the behavior old binaries expect and the new behavior.
 When an access violation occurs, old binaries expect a SIGBUS and an
si_code of BUS_PAGE_FAULT.  Presumably, we want new binaries to
receive a SIGSEGV when an access violation occurs.  This patch does
not consider whether we are running under an old or new binary.  Is
that really okay?