https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92906
--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by Jakub Jelinek <ja...@gcc.gnu.org>: https://gcc.gnu.org/g:994e0ad41529f5518fd013474a657968807d9ca5 commit r10-6630-g994e0ad41529f5518fd013474a657968807d9ca5 Author: Jakub Jelinek <ja...@redhat.com> Date: Fri Feb 14 00:11:24 2020 +0100 c++: Emit DFP typeinfos even when DFP is disabled [PR92906] Before Joseph's changes when compiling libstdc++-v3/libsupc++/fundamental_type_info.cc we were emitting _ZTIPDd, _ZTIPDe, _ZTIPDf, _ZTIPKDd, _ZTIPKDe, _ZTIPKDf, _ZTIDd, _ZTIDe, _ZTIDf symbols even when DFP wasn't usable, but now we don't and thus those 9 symbols @@CXXABI_1.3.4 are gone from libstdc++. While nothing could probably use it (except perhaps dlsym etc.), various tools don't really like symbols disappearing from symbol versioned shared libraries with stable ABI. Adding those in assembly would be possible, but would be a portability nightmare (the PR has something Red Hat uses in libstdc++_nonshared.a, but that can handle only a handful of linux ELF targets we care about). So, instead this patch hacks up the FE, so that it emits those, but in a way that won't make the DFP types available again on targets that don't support them. 2020-02-14 Jakub Jelinek <ja...@redhat.com> PR libstdc++/92906 * cp-tree.h (enum cp_tree_index): Add CPTI_FALLBACK_DFLOAT32_TYPE, CPTI_FALLBACK_DFLOAT64_TYPE and CPTI_FALLBACK_DFLOAT128_TYPE. (fallback_dfloat32_type, fallback_dfloat64_type, fallback_dfloat128_type): Define. * mangle.c (write_builtin_type): Handle fallback_dfloat*_type like dfloat*_type_node. * rtti.c (emit_support_tinfos): Emit DFP typeinfos even when dfp is disabled for compatibility.