plasma5-plasma-workspace-5.19.4 fails to build on -current with clang-11

[Michael Butler]

Without recompilation, I see an undefined symbol in
.local/share/sddm/xorg-session.log

ld-elf.so.1:
/usr/local/lib/qt5/qml/org/kde/plasma/wallpapers/image/libplasma_wallpaper_imageplugin.so:
Undefined symbol "_ZNSt3__18__rs_getEv"

In an effort to resolve this, I tried to recompile but it fails with:

FAILED: bin/libplasma_wallpaper_imageplugin.so
: && /usr/bin/c++ -fPIC -O2 -pipe -march=ivybridge
-fstack-protector-strong -fno-strict-aliasing -fno-operator-names
-fno-exceptions -Wno-gnu-zero-variadic-macro-arguments -Wall -Wextra
-Wcast-align -Wchar-subscripts -Wformat-security -Wno-long-long
-Wpointer-arith -Wundef -Wnon-virtual-dtor -Woverloaded-virtual
-Werror=return-type -Wvla -Wdate-time -fdiagnostics-color=always -O2
-pipe -march=ivybridge -fstack-protector-strong -fno-strict-aliasing
-Wl,--no-undefined -Wl,--fatal-warnings -Wl,--enable-new-dtags
-fstack-protector-strong -shared
-Wl,-soname,libplasma_wallpaper_imageplugin.so -o
bin/libplasma_wallpaper_imageplugin.so
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/plasma_wallpaper_imageplugin_autogen/mocs_compilation.cpp.o
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/image.cpp.o
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/imageplugin.cpp.o
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/backgroundlistmodel.cpp.o
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidemodel.cpp.o
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidefiltermodel.cpp.o
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/debug.cpp.o
 -Wl,-rpath,/usr/local/lib:/usr/local/lib/qt5:
/usr/local/lib/libKF5Plasma.so.5.73.0
/usr/local/lib/libKF5NewStuff.so.5.73.0
/usr/local/lib/qt5/libQt5Quick.so.5.15.0
/usr/local/lib/qt5/libQt5QmlModels.so.5.15.0
/usr/local/lib/qt5/libQt5Qml.so.5.15.0
/usr/local/lib/libKF5KIOWidgets.so.5.73.0
/usr/local/lib/libKF5KIOGui.so.5.73.0
/usr/local/lib/libKF5KIOCore.so.5.73.0
/usr/local/lib/qt5/libQt5Concurrent.so.5.15.0
/usr/local/lib/libKF5JobWidgets.so.5.73.0
/usr/local/lib/libKF5Service.so.5.73.0
/usr/local/lib/libKF5NewStuffCore.so.5.73.0
/usr/local/lib/libKF5Package.so.5.73.0
/usr/local/lib/libKF5XmlGui.so.5.73.0
/usr/local/lib/libKF5WindowSystem.so.5.73.0
/usr/local/lib/libKF5Attica.so.5.73.0
/usr/local/lib/qt5/libQt5Network.so.5.15.0
/usr/local/lib/libKF5Completion.so.5.73.0
/usr/local/lib/libKF5ConfigWidgets.so.5.73.0
/usr/local/lib/libKF5I18n.so.5.73.0
/usr/local/lib/libKF5WidgetsAddons.so.5.73.0
/usr/local/lib/libKF5Codecs.so.5.73.0
/usr/local/lib/libKF5ConfigGui.so.5.73.0
/usr/local/lib/libKF5ConfigCore.so.5.73.0
/usr/local/lib/qt5/libQt5Xml.so.5.15.0
/usr/local/lib/libKF5Auth.so.5.73.0
/usr/local/lib/libKF5AuthCore.so.5.73.0
/usr/local/lib/libKF5CoreAddons.so.5.73.0
/usr/local/lib/qt5/libQt5DBus.so.5.15.0
/usr/local/lib/qt5/libQt5Widgets.so.5.15.0
/usr/local/lib/qt5/libQt5Gui.so.5.15.0
/usr/local/lib/qt5/libQt5Core.so.5.15.0
-Wl,-rpath-link,/usr/local/lib:/usr/local/lib/qt5 && :
ld: error: undefined symbol: std::__1::__rs_get()
>>> referenced by slidefiltermodel.cpp
>>>
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidefiltermodel.cpp.o:(SlideFilterModel::buildRandomOrder())
>>> referenced by slidefiltermodel.cpp
>>>
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidefiltermodel.cpp.o:(SlideFilterModel::invalidate())
>>> referenced by slidefiltermodel.cpp
>>>
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidefiltermodel.cpp.o:(QtPrivate::QFunctorSlotObject<SlideFilterModel::setSourceModel(QAbstractItemModel*)::$_0,
0, QtPrivate::List<>, void>::impl(int, QtPrivate::QSlotObjectBase*,
QObject*, void**, bool*))

ld: error: undefined symbol: std::__1::__rs_default::~__rs_default()
>>> referenced by slidefiltermodel.cpp
>>>
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidefiltermodel.cpp.o:(SlideFilterModel::buildRandomOrder())
>>> referenced by slidefiltermodel.cpp
>>>
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidefiltermodel.cpp.o:(SlideFilterModel::invalidate())
>>> referenced by slidefiltermodel.cpp
>>>
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidefiltermodel.cpp.o:(QtPrivate::QFunctorSlotObject<SlideFilterModel::setSourceModel(QAbstractItemModel*)::$_0,
0, QtPrivate::List<>, void>::impl(int, QtPrivate::QSlotObjectBase*,
QObject*, void**, bool*))

ld: error: undefined symbol: std::__1::__rs_default::operator()()
>>> referenced by slidefiltermodel.cpp
>>>
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidefiltermodel.cpp.o:(long
std::__1::uniform_int_distribution<long>::operator()<std::__1::__rs_default>(std::__1::__rs_default&,
std::__1::uniform_int_distribution<long>::param_type const&))
>>> referenced by slidefiltermodel.cpp
>>>
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidefiltermodel.cpp.o:(long
std::__1::uniform_int_distribution<long>::operator()<std::__1::__rs_default>(std::__1::__rs_default&,
std::__1::uniform_int_distribution<long>::param_type const&))
>>> referenced by slidefiltermodel.cpp
>>>
wallpapers/image/CMakeFiles/plasma_wallpaper_imageplugin.dir/slidefiltermodel.cpp.o:(long
std::__1::uniform_int_distribution<long>::operator()<std::__1::__rs_default>(std::__1::__rs_default&,
std::__1::uniform_int_distribution<long>::param_type const&))
>>> referenced 1 more times
c++: error: linker command failed with exit code 1 (use -v to see
invocation)

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