[fpc-devel] Just to confirm, "with" behaviour expected

[Martin Frb]

In the below code, the array is resized (and more important relocated in 
mem) inside the function "bar".

The commented line (without "with") works as expected.

The "with" line has a different behaviour. I guess it is by design. Just 
wanted to confirm.

The version with "with" prints 12345 for  "  writeln(a[i,j].x);"
For all I can tell the return value of "bar" was written to the old 
address of that array-entry.

Does "with" take the "address" of the value, and operate on that 
address, even if the address of that value could change within the 
"with" statement.

- test was performed with
    fpc 3.2.3  -O1
    fpc 3.3.1  -O4


program Project1;
{$mode objfpc}

procedure outer;
   var
     a: array of array of record x:Integer; end;
     i, j: integer;

   function bar(x: integer): integer;
   begin
     Result := random(99) + 2 * x;
     writeln(Result);
     SetLength(a, 3000, 200);
   end;

   procedure foo;
   begin
     i := random(99);
     j := random(99);
     with a[i,j] do x:= bar(x);
     //a[i,j].x := bar(a[i,j].x);
   end;

begin
   SetLength(a, 100, 100);
   for i := 0 to 99 do
     for j := 0 to 99 do
       a[i,j].x := 12345;

   foo;
   writeln(a[i,j].x);
   readln;
end;

begin
   outer;
end.