It seems various applications have problems with the same Qt Declarative function.

I build every QT 5 component from the 5.4 branch in this order (as I used to use the qt5 super repo, but it seems declarative wasn't getting build once I switched to 5.4)
qtbase
qtmultimedia
qtsvg
qtsensors
qtimageformats
qtsystems
qt3d
qtxmlpatterns
qtwebkit
qtscript
qtdeclarative
qtquick1
qtquickcontrols
qttools
qtx11extras
qtwayland

with the options for qtbase:
-confirm-license -opensource -qpa -xcb -egl -prefix $INSTALLDIR -release -no-reduce-relocations -reduce-exports -dbus -no-gtkstyle -system-sqlite -openssl-linked -no-warnings-are-errors -no-separate-debug-info -nomake tests -nomake examples

In order to correct the stack trace in many of these, I have to run
(gdb) set $eip = *(void **)$esp
(gdb) set $esp = $esp + 4

The stacktrace of plasmashell is attached