using -fsplit-stack

[mathieu lacage]

On Fri, 2012-11-30 at 14:22 -0800, Ian Lance Taylor wrote:
> On Fri, Nov 30, 2012 at 1:09 PM, mathieu lacage
> <mathieu.lacage@cutebugs.net> wrote:
> >
> > Well, it seems to be segfaulting on my box because the default stack
> > space is smaller that the above (big ?) array.
> 
> Please reply to the mailing list, not just to me.  Thanks.

stupid mailer keeps ignoring my "reply all" :/

> 
> I see.  There does seem to be something wrong here; the split stack
> code ought to have allocated a new stack for you.
> 
> > How is this expected to
> > fail if I am not using gold ? (at link-time or run-time ?)
> 
> If you don't use gold your test case will fail at runtime because the
> main function won't realize that it needs to allocate enough stack
> space for printf.
> 
> > Are you aware of anyone who has tried to rebuild a distribution with
> > this flag and make the system gcc use this flag by default? It would be
> > nice from a usability perspective to not have to worry about stack size
> > ever without having to pay too high for this.
> 
> I am not aware of anybody who has done this.  I think it would be a
> significant effort.

Right. I am merely curious. Having -fsplit-stack work out of the box for
new binaries and libraries I compile on normal distributions is good
enough for me. I will report on further experiments, with PIE
executables on other distributions and with other gcc versions.

thanks a lot,
Mathieu