[PATCH] libio: Properly link in libio functions in static binaries

[H.J. Lu]

On Mon, Aug 25, 2025 at 6:09 AM Florian Weimer <fweimer@redhat.com> wrote:
>
> * H. J. Lu:
>
> >> Hmm.  The --strip-unneeded option says this:
> >>
> >>        --strip-unneeded
> >>            Remove all symbols that are not needed for relocation processing in
> >>            addition to debugging symbols and sections stripped by
> >>            --strip-debug.
> >>
> >> I think it's a user error to use this on libc.a.  What's the benefit of
> >
> > Why can't --strip-unneeded be used on libc.a? If a symbol isn't used for
> > relocation processing, it is unused.
>
> It's only unused from the individual .o file that the strip command
> processes.  It's not unused from a global perspective.  We'll add more

An undefined entry in the symbol table without relocation is unneeded
for "relocation processing".

> references like these once we improve support for static linking.
>
> Developers should run --strip-unneeded on the output file, not the input

The key word is "relocation processing".   Most of the outputs don't need
relocation processing.

> files, or use --strip-debug on libc.a.  Running --strip-unneeded on
> libc.a seems unnecessary.
>
> Thanks,
> Florian
>


-- 
H.J.