[fpc-pascal] Result: string

[José Mejuto]

El 04/03/2013 22:16, Michael Van Canneyt escribió:

>> That report says the issue was assigned to Jonas and fixed in revision
>> 20427 (ver 2.6.1).
>> I find the current release (2.6.2) initialises a string function
>> result to EmptyStr as you would hope.
[...]
> Prints AA

Hello,

I'm asking because today I has updated my old 2.7.1 SVN since 8-9 months 
and a library starts to fail and the "bug" was the Result string which 
enters the function with a value while it does not happend in the old one.

If Result as string is not initialized a warning should be issued do not 
? This happends in your simple test, but I was unable to find it in the 
library that I'm using.

The code that makes me wonder something is wrong is this one:

-----------------------------------
{$mode objfpc}
{$h+}

procedure TheB(var aTheA: string);

begin
   aTheA:=aTheA+'A';
end;

function TheA(): string;

begin
   //Result:='';
   TheB(Result);
end;

Var
   C : String;

begin
   C:='B';
   C:=TheA;
   C:=TheA;
   Writeln('= "',C,'"');
end.
-----------------------------------

In this situation no warning happends and result is different if I 
uncomment the "Result:='';" line.

I think the missing warning is a bug, the missing warning or the non 
initialization.

--