centos 7.1 编译 BNC错误

/clock_and_orbit -IRTCM3/rtcm3torinex -I../qwt -I../qwtpolar -I.moc/release -o .obj/release/bncwindow.o bncwindow.cpp
In file included from bncwindow.cpp:60:0:
bncsslconfig.h:8:29: error: invalid use of incomplete type ‘class QSslConfiguration’
 class bncSslConfig : public QSslConfiguration {
                             ^
In file included from /usr/local/Trolltech/Qt-4.8.5/include/QtNetwork/qabstractnetworkcache.h:48:0,
                 from /usr/local/Trolltech/Qt-4.8.5/include/QtNetwork/QtNetwork:7,
                 from bncgetthread.h:29,
                 from bncwindow.h:31,
                 from bncwindow.cpp:44:
/usr/local/Trolltech/Qt-4.8.5/include/QtNetwork/qnetworkrequest.h:56:7: error: forward declaration of ‘class QSslConfiguration’
 class QSslConfiguration;
       ^
make[1]: *** [.obj/release/bncwindow.o] Error 1
make[1]: Leaving directory `/home/zzh/programs/BNC-2.11.0/BNC/src'
make: *** [sub-src-make_default-ordered] Error 2
[zzh@zhaozhonghai BNC]$