Re: undefined __ia64_app_header with gc-3.0.4,glibc-2.5.5 on ia64

[Jim Wilson <wilson at redhat dot com>]

>ld says: undefined reference to `__ia64_app_header´
>what is missing?

You mixed code compiled by two different IA-64 gcc versions.  IA-64 is still so
new that practically every gcc release is ABI incompatible with every other
gcc release.  We won't have any hope of ABI compatibility until everyone is
using gcc-3.1.

I think this particular error occurs if you build a shared library with a gcc
3.0.0 or earlier compiler and then link it using a gcc 3.0.1 later compiler,
where the shared library imports functions from libgcc.  This is because
ia64_app_header is present in gcc 3.0.0 and earlier compilers, but not present
in gcc 3.0.1 and later compilers.  If you compile all shared libraries that
you are using (including system libraries like libc.so) with gcc-3.0.4 then
it should work.  That may be too much trouble though, and may not even be
possible because of compiler changes.

Jim