This is the strangest thing I have seen in Qt. Built a simple test application with one external library plus qwt.
Just one other source file plus the main window.

Compiles fine, runs fine, no errors. Then just change the title in the main window. Recompile (ok) and run and get the 1073741515 error. I have tried this in multiple little test projects and it happens every time.
Driving me nuts, any advice greatly appreciated.

Thanks
WaynePortaudio_Test.zip