QSharedMemory does not name a type

Has anyone come up with an error like that when making Qt? 

I'm remaking Qt, and the only difference I can think of is that QtCreator
is now installed on the same system. 

I had an error with an undefined reference of "get_time" and I got around
that by adding -lrt to the qmake.conf file. 

The total description of the error is as follows, 

[CODE]

make[3]: Leaving directory
`/usr/local/qt-everywhere-opensource-src-4.8.2/examples/ipc/sharedmemory'
make[3]: Entering directory
`/usr/local/qt-everywhere-opensource-src-4.8.2/examples/ipc/sharedmemory'
uic dialog.ui
compiling main.cpp
In file included from main.cpp:42:
dialog.h:65: error: 'QSharedMemory' does not name a type
make[3]: *** [.obj/release-shared-emb-arm/main.o] Error 1
make[3]: Leaving directory
`/usr/local/qt-everywhere-opensource-src-4.8.2/examples/ipc/sharedmemory'
make[2]: *** [sub-sharedmemory-make_default] Error 2
make[2]: Leaving directory
`/usr/local/qt-everywhere-opensource-src-4.8.2/examples/ipc'
make[1]: *** [sub-ipc-make_default] Error 2
make[1]: Leaving directory
`/usr/local/qt-everywhere-opensource-src-4.8.2/examples'
make: *** [sub-examples-make_default-ordered] Error 2
[/CODE]