When emerging qt-creator-3.4.0 I am getting the following error messages on my ~amd64 system: # export MAKEOPTS="-j1" && emerge -avt qt-creator [...] x86_64-pc-linux-gnu-g++ -Wl,-O1 -Wl,--as-needed -Wl,--hash-style=gnu -Wl,-z,origin '-Wl,-rpath,$ORIGIN:$ORIGIN/..:$ORIGIN/../lib64/qtcreator' -o ../../../bin/buildoutputparser .obj/release-shared/main.o .obj/release-shared/outputprocessor.o .obj/release-shared/moc_outputprocessor.o -L/tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator -L/tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/plugins -lProjectExplorer -lQtSupport -lQmakeProjectManager -lCore -lTextEditor -lCppTools -lResourceEditor -lQtcSsh -lQmlJS -lCPlusPlus -lAggregation -lExtensionSystem -lUtils -lLanguageUtils -lQt5Widgets -lQt5Gui -lQt5Concurrent -lQt5Network -lQt5Core -lGL -lpthread /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::DL_Group::DL_Group(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::PK_Signer::PK_Signer(Botan::Private_Key const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Botan::Signature_Format, Botan::Fault_Protection)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::X509::PEM_encode[abi:cxx11](Botan::Public_Key const&)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::Algorithm_Factory::prototype_hash_function(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::User_Interface::User_Interface(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::to_string[abi:cxx11](unsigned long long, unsigned long)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::Pipe::write(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::PK_Verifier::PK_Verifier(Botan::Public_Key const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, Botan::Signature_Format)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::PKCS8::PEM_encode(Botan::Private_Key const&, Botan::RandomNumberGenerator&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::PKCS8::PEM_encode[abi:cxx11](Botan::Private_Key const&)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::LibraryInitializer::initialize(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::PEM_Code::encode(Botan::MemoryRegion<unsigned char> const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, unsigned long)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::Algorithm_Factory::prototype_block_cipher(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' /tmp/portage/dev-qt/qt-creator-3.4.0/work/qt-creator-opensource-src-3.4.0/lib64/qtcreator/libQtcSsh.so: undefined reference to `Botan::Algorithm_Factory::make_hash_function(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&)' collect2: error: ld returned 1 exit status Makefile:188: recipe for target '../../../bin/buildoutputparser' failed [...]
Created attachment 402054 [details] dev-qt:qt-creator-3.4.0:20150426-130028.log.gz
Created attachment 402056 [details] The output of "emerge --info"
Are you using gcc-5 and you didn't rebuild @world?
Well I can't reproduce with gcc-4.9.2 and I'm quite sure that this is caused by the C++11 ABI incompatibilities introduced in gcc-5.1.
