Why do I see setup timing violations in my QDR II interface when Rapid Recompile is enabled in my Quartus II project?

Description

Due to a problem with the Rapid Recompile feature in the Quartus® II software versions 11.0 SP1 and earlier, you may see setup timing violations in your QDR II interface on paths crossing from the DDIO input registers (implemented in the I/O Cell) to the core of the FPGA.

An example of a typical failing path is shown below:

From:
<project hierarchy>|memphy_top_inst|umemphy|uio_pads|uread_pads|read_capture[0].uread_dq_dqs|input_dq_3_ddio_in_inst|regouthi

To:
<project hierarchy>|memphy_top_inst|umemphy|uread_datapath|read_buffering[0].read_subgroup[1].uread_fifo|data_stored*

To avoid this problem, turn off the Rapid Recompile feature.

This problem is scheduled to be fixed in a future version of the Quartus II software.

Resolution

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