add .cc files to libgcc.a

[Perry Smith]

This is on my quest to add __cxa_atexit to AIX's GCC.  I'm trying to port my patches to trunk.

David said I should move my two files to libgcc.a instead of libstdc++.a which is where I put them before.

These files define __cxa_finalize and __cxa_atexit.  These files are mostly from GNU's libc.

What I did was I added:

LIB2ADD += $(srcdir)/config/rs6000/cxa_atexit.cc $(srcdir)/config/rs6000/cxa_finalize.cc

to t-slibgcc-aix (mostly guessing what to do).  This resulted in:

Makefile:798: *** Unsupported files in LIB2ADD or LIB2ADD_ST..  Stop.

I'm assuming this is because they are C++ and not C but perhaps there is a different way to add them in.

My original logic in adding them to libstdc++.a is they are only used (called) by code automatically produced by g++ and not gcc.

But I'm happy to do / try whatever.

Thank you for your time,
Perry Smith