Found in the Qwt mailing list:
it seems that QT_STATIC_CONST got removed from qglobal.h
(see
https://qt.gitorious.org/qt/qtbase/commit/11c30f9705e796ebabcdd868bce3ad3664cc06eb
I noticed when updating to Qt 5.4).
The only place this still is in use in Qwt appears to be src/qwt_transform.h.
Fixed in SVN + I will have to do a Qwt 6.1.2 release, when Qt 5.4 has
been released.
Thanks for reporting,
Uwe