[OT] gcc, ssp, pie, and thunk

[walt]

On Tue, 13 Sep 2005, Eduardo Tongson wrote:

> You're using gentoo right ? ;)I think forums.gentoo.org is the
appropriate place to ask for clues

Excellent guess!  The reason I posted here is because the one big
weakness of gentoo is their forums website -- it always confuses
and frustrates me until I quit.

But -- I wouldn't use any other linux distro, and this is why:

In the unlikely event that anyone here is interested in my original
question --  by trial and error I found that the 'pie' (Position-
Independent-Executables) feature of gcc was causing my problem.

Much more important to the DFly project, however, is the spiffy
feature included in gentoo which allows multiple installations
of gcc on the same machine.

Yes, yes, I already have two different gcc's on DFly also.  The
extra feature that gentoo's 'gcc-config' provides is an app
called 'fix_libtool_files' (in perl, IIRC) which runs around
looking for those god-forsaken *.la (Libtool Archive) files which
are hard-wired to one version of g++ and patches them to reflect
your current choice of compiler versions.

It also switches between different flavors of (one) gcc version:

#ls -l /usr/lib/gcc-lib/i686-pc-linux-gnu/3.3.6/*.specs
-rw-r--r--  1 root root 4758 Sep 11 11:21 hardened.specs
-rw-r--r--  1 root root 4742 Sep 11 11:21 hardenednopie.specs
-rw-r--r--  1 root root 4738 Sep 11 11:21 hardenednopiessp.specs
-rw-r--r--  1 root root 4754 Sep 11 11:21 hardenednossp.specs
-rw-r--r--  1 root root 4758 Sep 11 11:21 specs
-rw-r--r--  1 root root 4736 Sep 11 11:21 vanilla.specs

This makes it trivial to use (or exclude) the ssp and/or the
pie features of gcc.  That is exactly the way I found that
'pie' was causing my problem.  Even an idiot like me can
do it :o)