Why does Qsys delete the IP generation directory contents?

Description

Due to a problem in the Quartus® II software version 14.0 Arria 10 Edition, the contents of the IP generation directory may be deleted after you edit your Qsys system. This problem occurs when you add a .qip file from a previous Qsys generation to a Quartus II project. In addition, the original .qip file is deleted.

Resolution

To work around this problem, when Qsys prompts you to regenerate the HDL files, always select Yes in the Qsys Generate Now? dialog box.