CONVERSION ERROR

[Fuhj-better]

Hello,
Is this syntax not supported?
Here is the code:

              integer i;
line 239   for (i = 0; i < N; i = i + 1)
          	if (i == 0)
				{co[i],sum[i]} = half_adder(a[i],b[i]);
			else
				{co[i],sum[i]} = full_adder(a[i],b[i],co[i-1]);

And here is the error message:

line 239: unknown identifier i
CONVERSION ERROR

Thank you for your help!

[kroening]

Did you forget the begin and end?

[Fuhj-better]

This is the complete part of the function in the code:

function [N:0] rca_N;

// parameter N = 8;
input [N-1:0] a;
input [N-1:0] b;

reg [N-1:0] co, sum;

begin : RCA // RIPPLE_CARRY_ADDER
    integer i;
    //for (i = 0; i <= N; i = i + 1)
    for (i = 0; i < N; i = i + 1)
        if (i == 0)
            {co[i], sum[i]} = half_adder(a[i], b[i]);
        else
            {co[i], sum[i]} = full_adder(a[i], b[i], co[i-1]);

    rca_N[N-1:0] = sum;
    // MSB is a sign bit
    rca_N[N] = (a[N-1] == b[N-1]) ? co[N-1] : sum[N-1];
end
endfunction

However, it can be compiled through using QuestaSim.
This is the error message indicating line 239:

for (i = 0; i < N; i = i + 1)

Did you forget the begin and end?