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Re: gEDA-user: Compilation problem with icarus 0.8.1?
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The problem is "m - 1'b1". The variable "m" is an integer which has
an indefinite width. (For example, it can have different widths on
different compilers.) Replace that with "reg signed [31:0]" if you
want to be explicit about its size.
Yes, other compilers will accept this, but they are all wrong:-)
Mark Schellhorn wrote:
| I have the following code snippet that fails compilation under icarus
| 0.8.1 with this message:
|
| [mark@camelot-007 DT_mark_cosim]$ iverilog junk.v
| junk.v:20: error: operand of concatenation has indefinite width:
| ((('d288)-(+d[4:0]))-((9'b000001000)-(c[2:0])))+({(+m[31:0])-(1'b1),
| 3'b000})
| 1 error(s) during elaboration.
|
| It looks like icarus doesn't like the "9'd256 + 9'd32", but I don't
| think there's anything illegal about it?
|
| module junk;
|
| integer d, e, m;
|
| reg [63:0] a;
| reg [(512*8)-1:0] b;
| reg [2:0] c;
|
| initial begin
| b = 0;
| c = 0;
| d = 0;
| m = 0;
| e = 9'd256 + 9'd32;
|
| // This one works
| a = b >> {(e - d[4:0] - (9'd8 - c) + {(m - 1'b1),3'o0}),3'o0};
|
| // This one doesn't
| a = b >> {(9'd256 + 9'd32 - d[4:0] - (9'd8 - c) + {(m -
| 1'b1),3'o0}),3'o0};
|
| $display("%m : 0x%h",a);
| end
| endmodule
|
- --
Steve Williams "The woods are lovely, dark and deep.
steve at icarus.com But I have promises to keep,
http://www.icarus.com and lines to code before I sleep,
http://www.picturel.com And lines to code before I sleep."
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