gcc on Red Hat EL 5.11 generating "GNU/Linux" OS/ABI binaries that are unusable on same system

[Jeff McWilliams <jeff dot mcwilliams at gmail dot com>]

I'm a developer for Altair, working on a large CAE program that we
support on Linux.


We've been building our tools with gcc/g++ 4.7.2 provided by the Red
Hat Developer Toolset 1.1 for some time now.

We build on RHEL 5.10 or 5.11

Recently I began looking on updating our tools to gcc/g++ 4.8.2 via
the Red Hat Developer Toolset 2.1

I'm compiling all our our code using the specified compiler, though
there are some
"third party" .so's that we link haven't changed.

Our runtime directory contains 151 .so's and one executable.

After building everything, there is ONE .so, and one executable that
is being created with OS/ABI set to "GNU/Linux" instead of "SYSV".
Because of the "GNU/Linux" tag on these two files, the .so and the
executable won't load or run on RHEL 5, including the machine that I'm
compiling/linking on.

I've tried using readelf to examine all the other .so's, as well as
.o's and any .a libs that get linked into these two files.  So far as
I can tell, they all have "SYSV" as the OS/ABI.  I can't find any
symbols with "IFUNC" set as the type.  The only glibc that we link
against is the one that comes on the system and/or whatever was
installed as part of Red Hat's Developer Toolset.

So far as I can understand from researching online, I shouldn't be
getting "GNU/Linux" OS/ABI binaries.  I haven't mixed newer glibc
runtimes on my Linux box, and I am not using libraries that were built
on newer platforms.

Can someone provide some additional tips or help about how I can
determine WHY the linker is setting the OS/ABI field to "GNU/Linux",
and what I can do to fix it?

I can provide the link line if that helps...

Thanks,

Jeff