https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67269
Bug ID: 67269 Summary: demangler does not handle constructor of substituted name correctly Product: gcc Version: 5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: ian at airs dot com CC: gbenson at redhat dot com Target Milestone: --- The demangler picks the constructor name based on the last name that it sees. It does not do this correctly when the last name is actually substituted. Here is a test case, which I concede is fairly insane. _ZNSt10_HashtableI12basic_stringIcSt11char_traitsIcESaIcEESt4pairIKS4_N1C1D1EEESaISA_ENSt8__detail10_Select1stESt8equal_toIS4_ESt4hashIS4_ENSC_18_Mod_range_hashingENSC_20_Default_ranged_hashENSC_20_Prime_rehash_policyENSC_17_Hashtable_traitsILb1ELb0ELb1EEEE9_M_assignIZNSN_C1ERKSN_EUlPKNSC_10_Hash_nodeISA_Lb1EEEE_EEvSQ_RKT_ The demangler turns this into void std::_Hashtable<basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E>, std::allocator<std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E> >, std::__detail::_Select1st, std::equal_to<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::hash<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, false, true> >::_M_assign<std::_Hashtable<basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E>, std::allocator<std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E> >, std::__detail::_Select1st, std::equal_to<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::hash<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, false, true> >::_M_assign(std::_Hashtable<basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E>, std::allocator<std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E> >, std::__detail::_Select1st, std::equal_to<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::hash<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, false, true> > const&)::{lambda(std::__detail::_Hash_node<std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E>, true> const*)#1}>(std::_Hashtable<basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E>, std::allocator<std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E> >, std::__detail::_Select1st, std::equal_to<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::hash<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, false, true> > const&, std::_Hashtable<basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E>, std::allocator<std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E> >, std::__detail::_Select1st, std::equal_to<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::hash<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, false, true> >::_M_assign(std::_Hashtable<basic_string<char, std::char_traits<char>, std::allocator<char> >, std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E>, std::allocator<std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E> >, std::__detail::_Select1st, std::equal_to<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::hash<basic_string<char, std::char_traits<char>, std::allocator<char> > >, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<true, false, true> > const&)::{lambda(std::__detail::_Hash_node<std::pair<basic_string<char, std::char_traits<char>, std::allocator<char> > const, C::D::E>, true> const*)#1} const&) I'm fairly sure that the second and third ::_M_assign should actually be ::_Hashtable. They are appearing in local-name productions. The relevant part of the mangled string is ZNSN_C1E. That is, a local-name with a constructor where the scope is from a substitution.