On Sat, Jan 10, 2026 at 07:04:53PM +0100, Jakub Jelinek wrote:
> On Sat, Jan 10, 2026 at 05:24:15PM +0100, Stefan Schulze Frielinghaus wrote:
> > libstdc++-v3/ChangeLog:
> >
> > * config/abi/post/s390x-linux-gnu/baseline_symbols.txt: Add
> > names {,P,K}DF16.
>
> This is wrong - an ABI issue.
>
> You can't export new symbols in CXXABI_1.3.14 symbol version when they
> weren't exported there in GCC 13.1 already.
> Symbols new in GCC 16 like these should be exported in CXXABI_1.3.17.
Yikes, you are absolutely right. It was also wrong in the first draft I
posted back in Nov. Thank you very much for double checking and
catching this! I will trigger a full test run of your patch and come
back to you.
Cheers,
Stefan
> So, I think you want (completely untested):
>
> 2026-01-10 Jakub Jelinek <[email protected]>
>
> * config/abi/pre/gnu.ver (CXXABI_1.3.14): Don't export _ZTI*DF16_ on
> s390x.
> (CXXABI_1.3.17): Export _ZTI*DF16_ on s390x.
> * config/abi/post/s390x-linux-gnu/baseline_symbols.txt: Remove
> _ZTI{,P,K}DF16_.
>
> --- libstdc++-v3/config/abi/pre/gnu.ver.jj 2026-01-02 09:56:10.583329488
> +0100
> +++ libstdc++-v3/config/abi/pre/gnu.ver 2026-01-10 18:58:37.133669626
> +0100
> @@ -2899,9 +2899,16 @@ CXXABI_1.3.14 {
>
> # typeinfo for _Float{16,32,64,128,32x,64x,128x} and
> # __bf16/bfloat16_t
> +#ifndef __s390x__
> _ZTIDF[0-9]*[_x];
> _ZTIPDF[0-9]*[_x];
> _ZTIPKDF[0-9]*[_x];
> +#else
> + # No _Float16 on s390x in GCC 13.
> + _ZTIDF[0-9]*[0-57-9][_x];
> + _ZTIPDF[0-9]*[0-57-9][_x];
> + _ZTIPKDF[0-9]*[0-57-9][_x];
> +#endif
> #ifndef __riscv
> _ZTIDF16b;
> _ZTIPDF16b;
> @@ -2933,6 +2940,13 @@ CXXABI_1.3.16 {
> CXXABI_1.3.17 {
> # std::exception_ptr::_M_exception_ptr_cast
>
> _ZNKSt15__exception_ptr13exception_ptr21_M_exception_ptr_castERKSt9type_info;
> +
> +#ifdef __s390x__
> + _ZTIDF16_;
> + _ZTIPDF16_;
> + _ZTIPKDF16_;
> +#endif
> +
> #ifdef __riscv
> } CXXABI_1.3.16;
> #else
> --- libstdc++-v3/config/abi/post/s390x-linux-gnu/baseline_symbols.txt.jj
> 2026-01-10 18:52:48.533640534 +0100
> +++ libstdc++-v3/config/abi/post/s390x-linux-gnu/baseline_symbols.txt
> 2026-01-10 18:59:02.224239870 +0100
> @@ -4951,7 +4951,6 @@ OBJECT:15:_ZTSSt8messagesIwE@@GLIBCXX_3.
> OBJECT:15:_ZTSSt8numpunctIcE@@GLIBCXX_3.4
> OBJECT:15:_ZTSSt8numpunctIwE@@GLIBCXX_3.4
> OBJECT:16:_ZTIDF128_@@CXXABI_1.3.14
> -OBJECT:16:_ZTIDF16_@@CXXABI_1.3.14
> OBJECT:16:_ZTIDF32_@@CXXABI_1.3.14
> OBJECT:16:_ZTIDF32x@@CXXABI_1.3.14
> OBJECT:16:_ZTIDF64_@@CXXABI_1.3.14
> @@ -5616,7 +5615,6 @@ OBJECT:30:_ZTSSt7codecvtIDsDu11__mbstate
>
> OBJECT:32:_ZNSbIwSt11char_traitsIwESaIwEE4_Rep20_S_empty_rep_storageE@@GLIBCXX_3.4
> OBJECT:32:_ZNSs4_Rep20_S_empty_rep_storageE@@GLIBCXX_3.4
> OBJECT:32:_ZTIPDF128_@@CXXABI_1.3.14
> -OBJECT:32:_ZTIPDF16_@@CXXABI_1.3.14
> OBJECT:32:_ZTIPDF32_@@CXXABI_1.3.14
> OBJECT:32:_ZTIPDF32x@@CXXABI_1.3.14
> OBJECT:32:_ZTIPDF64_@@CXXABI_1.3.14
> @@ -5629,7 +5627,6 @@ OBJECT:32:_ZTIPDn@@CXXABI_1.3.5
> OBJECT:32:_ZTIPDs@@CXXABI_1.3.3
> OBJECT:32:_ZTIPDu@@CXXABI_1.3.12
> OBJECT:32:_ZTIPKDF128_@@CXXABI_1.3.14
> -OBJECT:32:_ZTIPKDF16_@@CXXABI_1.3.14
> OBJECT:32:_ZTIPKDF32_@@CXXABI_1.3.14
> OBJECT:32:_ZTIPKDF32x@@CXXABI_1.3.14
> OBJECT:32:_ZTIPKDF64_@@CXXABI_1.3.14
>
>
> Jakub
>
