Why does the Intel® Arria®10 Low Latency 10G MAC 1G/2.5G/10G (preset) Example Design show timing failure?

Due to an optimization problem, when using the 1G/2.5G/10G Arria® 10 Low Latency Ethernet MAC Example Design, setup timing failures may be seen between the soft PCS to 10G hard PCS transfer.

To work around this setup timing failure, under-constrain the hold time of the transfer from soft PCS to 8G hard PCS to ease setup timing closure using the constraint below:

if {![string equal "quartus_sta" $::TimeQuestInfo(nameofexecutable)] } {
set_min_delay -from [get_keepers *|alt_mge16_phy_xcvr_term:*|tx_parallel_data_a10*] -to [get_keepers *|twentynm_pcs*:*|gen_twentynm_hssi_8g_tx_pcs.inst_twentynm_hssi_8g_tx_pcs~tx_clk2_by2_1.reg] -0.2ns
}

This problem is not scheduled to be fixed in a future version of the Intel® Quartus® Prime Edition Software.