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Re: [PATCH] Fix NO_LIBPCRE1_JIT to fully disable JIT

On Mon, Nov 13, 2017 at 12:53:15PM +0900, Junio C Hamano wrote:
> Thanks.  This patch needs a sign-off, by the way.

Signed-off-by: cbailey32@xxxxxxxxxxxxx

(I can resend the full patch if required or if anyone requests futher

> > But that we should take it anyway regardless of that since it'll *also*
> > work on Linux with your patch, and this logic makes some sense whereas
> > the other one clearly didn't and just worked by pure accident of some
> > toolchain semantics that I haven't figured out yet.
> That is curious and would be nice to know the answer to.

The error that I was getting - if I remember the details of the very
brief debugging session that I performed - was an unaligned memory
access causing a SIGBUS in PCRE code whose function name contained 'jit'
and which was being called indirectly from pcre_study.

My guess is that we are just exposing a pre-existing bug in our Solaris
build of libpcre. Unaligned memory accesses on x86 / x86_64 "only" cause
performance issues rather than fatal signals so even if the same bug
exists on Linux it probably has no noticeable effect (or at least no
noticed effect).