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POWhich variables are initialized when in Delphi?
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copied!<p>So I always heard that class fields (heap based) were initialized, but stack based variables were not. I also heard that record members (also being stack based) were also not initialized. The compiler warns that local variables are not initialized ([DCC Warning] W1036 Variable 'x' might not have been initialized), but does not warn for record members. So I decided to run a test. </p> <p>I always get <strong>0</strong> from <em>Integers</em> and <strong>false</strong> from <em>Booleans</em> for all record members. </p> <p>I tried turning various compiler options (debugging, optimizations, etc.) on and off, but there was no difference. All my record members are being initialized.</p> <p>What am I missing? I am on Delphi 2009 Update 2. </p> <pre><code>program TestInitialization; {$APPTYPE CONSOLE} uses SysUtils; type TR = Record Public i1, i2, i3, i4, i5: Integer; a: array[0..10] of Integer; b1, b2, b3, b4, b5: Boolean; s: String; End; var r: TR; x: Integer; begin try WriteLn('Testing record. . . .'); WriteLn('i1 ',R.i1); WriteLn('i2 ',R.i2); WriteLn('i3 ',R.i3); WriteLn('i4 ',R.i4); WriteLn('i5 ',R.i5); Writeln('S ',R.s); Writeln('Booleans: ', R.b1, ' ', R.b2, ' ', R.b3, ' ', R.b4, ' ', R.b5); Writeln('Array '); for x := 0 to 10 do Write(R.a[x], ' '); WriteLn; WriteLn('Done . . . .'); except on E:Exception do Writeln(E.Classname, ': ', E.Message); end; ReadLn; end. </code></pre> <p><strong>Output:</strong></p> <pre> Testing record. . . . i1 0 i2 0 i3 0 i4 0 i5 0 S Booleans: FALSE FALSE FALSE FALSE FALSE Array 0 0 0 0 0 0 0 0 0 0 0 Done . . . . </pre>

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