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55 lines
1.1 KiB
ObjectPascal
55 lines
1.1 KiB
ObjectPascal
type
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TMyType = cardinal;
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tr = record
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a,b,c,d: byte;
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end;
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procedure t(var l: cardinal);
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begin
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if (l <> $cafebabe) then
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halt(4);
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l := $c001d00d;
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end;
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var
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Item: TMyType;
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ItemAsByte: byte absolute Item;
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r: tr;
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b: byte absolute r.b;
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l: cardinal;
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labs: cardinal absolute l;
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begin
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{ Of course I understand fully that this code is bad
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(unless you really want to read the 1st byte of 4-byte LongInt
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type, messing with endianess problems).
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In real code, I accessed ItemAsByte only when
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SizeOf(TMyType) = 1 (the code is
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used like a simple template, so it must work with any
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TMyType, and the case when SizeOf(TMyType) = 1 uses some
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specially optimized versions (e.g. FillChar(..., ItemAsByte)
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can be used in this case to fill the array of TMyType). }
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{$ifdef FPC_BIG_ENDIAN}
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item:=$deadbeef;
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{$else}
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item:=$efbeadde;
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{$endif}
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if (itemasbyte <> $de) then
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halt(1);
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r.a := $de;
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r.b := $ad;
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r.c := $be;
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r.d := $ef;
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if (b <> $ad) then
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halt(2);
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l := $cafebabe;
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t(labs);
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if (l <> $c001d00d) then
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halt(6);
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end.
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