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4682ac269d
An uninitialized function Result of a managed type needs special handling.
When passing it as a var parameter a warning need to be emitted, since a user
may expect Result to be empty (nil) by default as it happens with local vars
of a managed type. But this is not true for Result and may lead to serious issues.
The only exception is SetLength(Result, ?) for a string Result. A user always
expects undefined contents of the string after calling SetLength(). In such
case a hint need to be emitted.
+ Tests for this.
git-svn-id: trunk@40216 -
65 lines
1.1 KiB
ObjectPascal
65 lines
1.1 KiB
ObjectPascal
{ %norun }
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{ %opt=-Sewn -vwn -O- }
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{
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Test for correct emitting of warnings/hints for uninitialized variables of management types
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See also tbf/tb0258.pp
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}
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// Only hints about uninitialized managed variables must be issued for this code
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{$mode objfpc}
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type
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TLongArray = array of longint;
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procedure p;
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var
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a : TLongArray;
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s: ansistring;
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begin
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setlength(a,100); // hint for local var
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setlength(s,100); // hint for local var
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a[1]:=1;
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writeln(a[1]);
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s[1]:='a';
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writeln(s[1]);
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end;
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procedure svar(var s: ansistring; len: longint);
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begin
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setlength(s,len);
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end;
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procedure avar(var a: TLongArray; len: longint);
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begin
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setlength(a,len);
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end;
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procedure p2;
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var
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a : TLongArray;
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s: ansistring;
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begin
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avar(a,100); // hint for local var
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svar(s,100); // hint for local var
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a[1]:=1;
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writeln(a[1]);
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s[1]:='a';
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writeln(s[1]);
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end;
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function f2: ansistring;
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begin
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// Hint for the ansistring Result, since all contents of the Result
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// after calling SetLength() is expected to be undefined.
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setlength(Result,1);
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Result[1]:='a';
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end;
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begin
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p;
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p2;
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f2;
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end.
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