Fan Out Problem..

Hello FPGA gurus..

I am designing a micro using Quartus II v4.0 and the target FPGA is Flex10K (EPF10K20RC240-4). I know it's a very outdated FPGA, but that's all I have :( The ALU unit when I compile stand along compiles and works as expected. However when the ALU is combined with the rest of the micro, during 'analysis & synthesis' I get a long list of warning.. .. here is the warning list

----------- Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00040|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00038|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00036|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00034|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00032|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00030|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00028|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00026|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00024|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00022|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00020|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00018|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00016|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00014|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00012|muxlut:$00018|$00012 contains fan-out to more than one destination Warning: CASCADE primitive SneakALU:ALU|lpm_mux:Mux|muxlut:$00010|muxlut:$00018|$00012 contains fan-out to more than one destination

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After this stage, QII crashes and gives the following error (with option to contact Altera)

---------- Internal Error: Sub-system: FTM, File: ftm_main.cpp, Line: 5851 oterm->get_number_of_fanout() == 1 Quartus II Version 4.0 Build 190 1/28/2004 SJ Full Version

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Now I have only one mux in my ALU. All that mux does is decides which result to put on the output result bux depending on the value of the sel line (which is decided in some other module).. The code of the lpm_mux is as follows:

---------- Gen_2D_Out2 : FOR sig_Cnt IN 0 TO 15 GENERATE sig_Output_Array (0, sig_Cnt) ALU_Result );

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Can someone pls help me with this problem.. Thanks in advance

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