On Tue, 18 Apr 2023 at 17:13, Jonathan Wakely <jwakely@redhat.com> wrote:
>
> On Tue, 18 Apr 2023 at 16:59, Jonathan Wakely via Libstdc++
> <libstdc++@gcc.gnu.org> wrote:
> > diff --git a/libstdc++-v3/config/abi/pre/gnu.ver b/libstdc++-v3/config/abi/pre/gnu.ver
> > index 4ae63094eb7..7c015524b62 100644
> > --- a/libstdc++-v3/config/abi/pre/gnu.ver
> > +++ b/libstdc++-v3/config/abi/pre/gnu.ver
> > @@ -2512,6 +2512,20 @@ GLIBCXX_3.4.31 {
> >      _ZNKSt12__shared_ptrINSt10filesystem28recursive_directory_iterator10_Dir_stackELN9__gnu_cxx12_Lock_policyE[012]EEcvbEv;
> >      _ZNKSt12__shared_ptrINSt10filesystem7__cxx1128recursive_directory_iterator10_Dir_stackELN9__gnu_cxx12_Lock_policyE[012]EEcvbEv;
> >
> > +#if defined(_GLIBCXX_SYMVER_GNU) && defined(_GLIBCXX_SHARED) \
> > +    && defined(_GLIBCXX_HAVE_AS_SYMVER_DIRECTIVE) \
> > +    && defined(_GLIBCXX_HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT)
>
> I've just noticed that these will never be defined, because this
> linker script is preprocessed with config.h not c++config.h, and so it
> should be:
>
> #if defined(_GLIBCXX_SYMVER_GNU) && defined(_GLIBCXX_SHARED) \
>     && defined(HAVE_AS_SYMVER_DIRECTIVE) \
>     && defined(HAVE_SYMVER_SYMBOL_RENAMING_RUNTIME_SUPPORT)
>
>
> The condition will never be true as currently written (which doesn't
> actually seem to matter, but Jakub says that re-exporting the symbols
> as the new version is needed in the linker script for older linkers).

Fixed with this patch, pushed to trunk and gcc-13 (after Jakub's approval).

Tested x86_64-linux and sparc-solaris2.11