Since qVersion() might be called also from C code, disable the parts of
qlibraryinfo.h that are relevant only for C++ code if __cplusplus is not
defined.
[ChangeLog][Potentially Source-Incompatible Changes] qVersion() is
moved from qglobal.h to qlibraryinfo.h, '#include <QtCore/QLibraryInfo>'
needs to be added where it's used.
Task-number: QTBUG-99313
Change-Id: I3363ef3fa4073114e5151cb3a2a1e8282ad42a4d
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>