Give a better error for PCH with exec-shield-randomize

[Geoff Keating]

> From: Ian Lance Taylor <ian@wasabisystems.com>
> Date: 04 Mar 2004 16:14:56 -0500

> Geoff Keating <geoffk@desire.geoffk.org> writes:
> 
> > I really don't like the ggc_pch_overlap part.  I don't like it for
> > three reasons:
> 
> OK, instead I wrote some code which makes the PCH testsuite work on
> Linux with exec-shield-randomize.
> 
> I don't have a good way to do some real testing without using the
> testsuite, though.  It's pretty hard to be confident that this will
> always do the right thing.

I'm pretty sure that this will sometimes go wrong, because it doesn't
really prevent the kernel (or prelink) from randomly deciding to map
something in the space that the PCH file wants.  It's a definite step
in the right direction, though.

-- 
- Geoffrey Keating <geoffk@geoffk.org>