https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69136
--- Comment #4 from Jan Hubicka <hubicka at gcc dot gnu.org> --- Aha, it is abstract decl. I am testing: Index: ../../gcc/lto/lto-symtab.c =================================================================== --- ../../gcc/lto/lto-symtab.c (revision 232466) +++ ../../gcc/lto/lto-symtab.c (working copy) @@ -987,6 +1008,8 @@ lto_symtab_merge_symbols (void) tree lto_symtab_prevailing_virtual_decl (tree decl) { + if (DECL_ABSTRACT_P (decl)) + return decl; gcc_checking_assert (!type_in_anonymous_namespace_p (DECL_CONTEXT (decl)) && DECL_ASSEMBLER_NAME_SET_P (decl));