[fpc-pascal] set addition bug?

[Adam Naumowicz]

Hi Peter,

On Tue, 12 Feb 2008, Peter Vreman wrote:

> Adam Naumowicz wrote:
>> Hello again,
>> 
>> On Mon, 11 Feb 2008, Adam Naumowicz wrote:
>> 
>>> Hello,
>>> 
>>> I'd like to know if this is a known issue, or a new bug.
>>> 
>>> With the following code:
>>> ------------------
>>> program tester;
>>> 
>>> type SomeType = ( SomeElem );
>>> 
>>> const ElemSet = [ SomeElem ];
>>> 
>>> begin
>>>   writeln(SomeElem in ElemSet);
>>>   writeln(SomeElem in (ElemSet + []));
>>> end.
>>> ------------------
>>> 
>>> one gets:
>>> 
>>> TRUE
>>> FALSE
>>> 
>>> while it should rather be
>>> 
>>> TRUE
>>> TRUE
>>> 
>>> The problem concerns FPC 2.2.0 on i386/Linux. Actually, I was tracing a 
>>> bug that was only visible with 2.2.0 while the 2.0.0 version of the 
>>> compiler did not produce an errorneous code on that. Unfortunately, I 
>>> didn't succeed to separate a small snippet of code responsible for that - 
>>> in that case, however, the set after the '+' was another set constant, not 
>>> an empty set, so the problem is rather general. As I said, with 2.0.0 the 
>>> boolean value was correct, while with 2.2.0 it was plain wrong.
>> 
>> It seems I've found an example that produces 'FALSE' with 2.2.0 and 'TRUE' 
>> with 2.0.0 trying to eliminate my code as much as possible - the piece is 
>> still a bit longish, so I attach it as a separate file - it seems, however, 
>> that removing lines any further 'hides' the bug.
>> 
>> I hope it will help you find the solution for this nasty problem.
>
> Fixed in 2.3.1 in r10311.

Thanks a lot for your quick response. Surely it solves the problem with 
empty set as the second parameter. But I'm not sure if the other code I 
sent later would also be fixed? - apparently that one had incorrect 
valuation when tested with official 2.2.0 for Win32 - and there the second 
argument was nonempty.

What do you think?

Best,

Adam

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