[fpc-pascal]BUG 1222: CASE/OF Bug

[Michael Knapp]

Michael Knapp wrote:
> 
> I have found a Bug in FPC (1.0.2 [2000/10/12])
> I have submitted it as Bug 1222:
> 
> this code displays "case failed, but it should not", but it shouldn't
> 
> CONST
>     c1=$80000000;
>     c2=$80000001;
>     c3=$80000002;
>     c4=$80000003;
> 
> VAR v:dword;
> 
> BEGIN
>   v:=c2;
>   CASE v OF
>     c1,c2:writeln('case c1,c2');
>     c3,c4:writeln('case c3,c4');
>     ELSE writeln('case failed, but it should not');
>   END;
> END.

the problem/solution:

# [13] v:=c2;
	movl	$-2147483647,_V
# [14] CASE v OF
	movl	_V,%eax   EAX=80000001h
	subl	$1,%eax   EAX=80000000h, SF=1, ZF=0, CF=0
	jbe	.L3       Jump if (ZF=1) OR (CF=1) - NO JUMP
	subl	$1,%eax   EAX=7FFFFFFFh, SF=0, ZF=0, CF=0
	jb	.L12      Jump if (CF=1) - NO JUMP
	subl	$1,%eax   EAX=7FFFFFFEh, SF=0, ZF=0, CF=0
	jbe	.L6       jump if (ZF=1) OR (CF=1) - NO JUMP
	jmp	.L12      JUMP to .L12
  .L6:
  .L13:
# [16] c3,c4:writeln('case c3,c4');
[...code snipped...]
  .L3:
  .L17:
# [15] c1,c2:writeln('case c1,c2');
  [...code snipped...]
  .L12:
  .L21:
# [17] ELSE writeln('case failed, but it should not');
  [...code snipped...]
  .L11:
# [19] END.

Michael

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|  Michael Knapp - Mauerbach - Niederösterreich - Austria - Europe   |
|  E-Mail: mknapp at gmx.at                             ICQ: 36542787   |
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