Re: `exec shield' test in configure too strict?

[Jan D.]

> > Another idea: can `main' contain code to move its heap address to the
> > desired place, at startup?
>
>     No, as the desired place is not a mapped memory region, you can 
> not write
>     there.
>
> How about mapping a memory region at the desired place, then
> putting the heap address there?

It could work, but sounds tricky, you would have to mmap exactly
between BSS and the heap.  It is possible that the kernel could
reject such a request.  I haven't tested it though.

>       But we could do as described by Camm Maguire, check if the heap 
> is not
>     at the correct place at temacs startup, and if it is not, call
>     personality(LINUX32) and exec() temacs again.
>
> That also seems like a good method, perhaps better.  It would require
> testing whether the symbols pertaining to personalites are developed,
> but that is a test done by compilation, so it should be 
> unproblematical.

I have checked in this method now.  I actually have an unexelf.c that 
works
with exec-shield on now, but I have only tested it on Fedora Core 2.  It
is probably too risky to check it in this close to a release.

        Jan D.