[Lazarus] Assignment on exception (was Re: exception handling in constructor)

[waldo kitty]

On 3/2/2013 08:25, Xiangrong Fang wrote:
> I guess there is really a bug, see the following:
> ==============================
>    f := 123;
>    try
>      f := ln(0);
>    except
>    end;
>    //WriteLn(f);
>    //{
>    if f = 123 then
>      WriteLn('f=123, not modified')
>    else
>      WriteLn('f is modified to:', f);
>    //}
> ===============================
>
> If I just WriteLn(f), it output Nan, I think there is some magic happening here.
>
> If I try to use if-then on f, then I get:
>
> An unhandled exception occurred at $000000000040028C :
> EDivByZero : Division by zero
>    $000000000040028C line 18 of project1.lpr

i am unable to reproduce this...

Lazarus 1.1 r39940 FPC 2.6.0 i386-win32-win32/win64


i started a new Simple Program project and pasted your above code into it...

C:\Documents and Settings\nil>LOCALS~1\Temp\project1
f=123, not modified


program Project1;

var
   f : extended;

begin
   f := 123;
     try
       f := ln(0);
     except
     end;
     //WriteLn(f);
     //{
     if f = 123 then
       WriteLn('f=123, not modified')
     else
       WriteLn('f is modified to:', f);
     //}
end.


so i started a new Program project and again...

C:\Documents and Settings\nil>LOCALS~1\Temp\project1
f=123, not modified


program Project1;

{$mode objfpc}{$H+}

uses
   {$IFDEF UNIX}{$IFDEF UseCThreads}
   cthreads,
   {$ENDIF}{$ENDIF}
   Classes
   { you can add units after this };

var
   f : extended;

begin
   f := 123;
     try
       f := ln(0);
     except
     end;
     //WriteLn(f);
     //{
     if f = 123 then
       WriteLn('f=123, not modified')
     else
       WriteLn('f is modified to:', f);
     //}
end.


what am i missing??