Getting multiple fan-out errors when compiling a scratch Nios with DDR SDRAM support

Just a quick note to say I hit the same problem and used the same solution - changing the clocks and dqs to inout.

output wire ddr2_ec_local_refresh_ack, // ddr2_ec.local_refresh_ack

output wire ddr2_ec_local_init_done, // .local_init_done

output wire ddr2_ec_reset_phy_clk_n, // .reset_phy_clk_n

output wire [0:0] ddr2_m_mem_odt, // ddr2_m.mem_odt

inout wire [0:0] ddr2_m_mem_clk, // .mem_clk

inout wire [0:0] ddr2_m_mem_clk_n, // .mem_clk_n

output wire [0:0] ddr2_m_mem_cs_n, // .mem_cs_n

output wire [0:0] ddr2_m_mem_cke, // .mem_cke

output wire [12:0] ddr2_m_mem_addr, // .mem_addr

output wire [1:0] ddr2_m_mem_ba, // .mem_ba

output wire ddr2_m_mem_ras_n, // .mem_ras_n

output wire ddr2_m_mem_cas_n, // .mem_cas_n

output wire ddr2_m_mem_we_n, // .mem_we_n

inout wire [31:0] ddr2_m_mem_dq, // .mem_dq

inout wire [3:0] ddr2_m_mem_dqs, // .mem_dqs

output wire [3:0] ddr2_m_mem_dm // .mem_dm