We still need those old frame functions in libgcc.a

[H.J. Lu]

> > 1. Say binary "foo" needs libbar.so, since __register_frame
> > is in libbar.so, linker will leave __register_frame
> > undefined in foo and the dynamic linker will find
> > __register_frame in libbar.so at the runtime.
> 
> Why would the linker add undefined symbols that are not used by foo, but
> rather shared libraries linked with foo?  I don't think any linker actually
> works that way.  libbar.so can look out for its own undefined symbols.
> 

__register_frame/__register_frame_info is referenced by
every single binary, shared library or program, via
crtbegin.o on platforms which use DWARF2 unwind info.


H.J.