Re: Git 2.18: RUNTIME_PREFIX... is it working?

From: Jeff King <peff@peff.net>
Date: Jul 10, 2018, 03:56 UTC
Message-ID: <20180710035635.GA13459@sigill.intra.peff.net>
In-Reply-To: <20180709195822.GA9000@sigill.intra.peff.net>

On Mon, Jul 09, 2018 at 03:58:22PM -0400, Jeff King wrote:

Show 15 quoted lines

> On Sun, Jul 08, 2018 at 11:52:22PM +0200, Johannes Schindelin wrote:
> 
> > Now, if you care to have a look at Dan's (and my) patches to implement
> > RUNTIME_PREFIX so that it looks for a directory *relative to the Git
> > binary*, you will see that it is far from portable. In fact, it is very
> > definitely not portable, and needs specific support for *every single
> > supported Operating System*. And while we covered a lot, we did not cover
> > all of them.
> > 
> > So unfortunately, it is impossible to make it the default, I am afraid.
> 
> Would it be reasonable to make RUNTIME_PREFIX the default on systems
> where we _do_ have that support? AFAIK there is no downside to having it
> enabled (minus a few syscalls to find the prefix, I suppose, but I
> assume that's negligible).

Brainstorming a little more on "what could be the possible downsides".

If I understand correctly, the Linux implementation requires reading from /proc. So an executable that only did RUNTIME_PREFIX (with no fallback to static paths) would be unhappy inside a chroot or other container that didn't mount /proc.

-Peff