On 7/26/2013 04:38, Peter Klotz wrote: > The build of Qt5Core.dll was done with Visual Studio, not with cygwin/gcc. Qt is a C++ library. C++ compiler output is not cross-compiler compatible. Unless I'm wrong, and this one DLL is pure C, you're not going to be able to link it to a C++ program built with GCC. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple