Re: [Gnustep-cvs] r26723 - in /libs/base/trunk: ChangeLog Headers/Additions/GNUstepBase/config.h.in Source/GSFFIInvocation.m configure configure.ac

[David Chisnall]

On 28 Jun 2008, at 10:56, David Ayers wrote:

> Richard Frith-Macdonald schrieb:
> > Author: rfm
> > Date: Sat Jun 28 07:13:47 2008
> > New Revision: 26723
> >
> > URL: http://svn.gna.org/viewcvs/gnustep?rev=26723&view=rev
> > Log:
> > Try to ensure that ffi uses executable memory and doesn't segfault
>
> Ahh! Yes, mmap! Thank you!

I think calling mmap directly is the wrong solution here.  You should  
be using valloc() with the requested size rounded up to the nearest  
page size, and then use mprotect to set it as executable.  Note that  
most sane operating systems (and Vista) are moving to W^X, so you need  
to set it as writeable while creating it, then executable while using  
it (i.e. call mprotect immediately before the return).

David