Hi.
This topic writen U in Japanese D Language Wiki.
http://f17.aaa.livedoor.jp/~labamba/?BugTrack%2F19

foo(-288*1000/360) is not -800.



void main(char[][] arg) {
printf("ok %d\n",  3/3);// 1
printf("ok %d\n", -(3/3));// -1

printf("ng %d\n", -3/3);// 1431655764
int a = cast(int)(-3/3);
printf("ng %d\n", a);// 1431655764
printf("ng %d\n", (-3)/3);// 1431655764
}

Hiroshi Sakurai wrote:
> Hi.
> This topic writen U in Japanese D Language Wiki.
> http://f17.aaa.livedoor.jp/~labamba/?BugTrack%2F19
> 
> foo(-288*1000/360) is not -800.
> 
> 
> 
> void main(char[][] arg) {
> printf("ok %d\n",  3/3);// 1
> printf("ok %d\n", -(3/3));// -1
> 
> printf("ng %d\n", -3/3);// 1431655764
> int a = cast(int)(-3/3);
> printf("ng %d\n", a);// 1431655764
> printf("ng %d\n", (-3)/3);// 1431655764
> }
> 
> 

Already reported. See D.bugs:4750.

zwang wrote:
> Hiroshi Sakurai wrote:
> 
>> Hi.
>> This topic writen U in Japanese D Language Wiki.
>> http://f17.aaa.livedoor.jp/~labamba/?BugTrack%2F19
>>
>> foo(-288*1000/360) is not -800.
>>
>>
>>
>> void main(char[][] arg) {
>> printf("ok %d\n",  3/3);// 1
>> printf("ok %d\n", -(3/3));// -1
>>
>> printf("ng %d\n", -3/3);// 1431655764
>> int a = cast(int)(-3/3);
>> printf("ng %d\n", a);// 1431655764
>> printf("ng %d\n", (-3)/3);// 1431655764
>> }
>>
>>
> 
> Already reported. See D.bugs:4750.

but this is kind of different, it's not treated as positive (or atleast doesn't seem like that)

funny thing is, -2/2 works fine!!
and so does -3/1

it's kind of odd .. in some cases it works, some cases it doesn't .. maybe an optamization bug?

<bug.d>
void main(char[][] arg)
{
    printf("-5/3 prints: %d\n", -5/3);
    printf("-5/2 prints: %d\n", -5/2);
    printf("-7/3 prints: %d\n", -7/3);
    printf("-7/4 prints: %d\n", -7/4);
    printf("-7/7 prints: %d\n", -7/7);
    printf("-8/7 prints: %d\n", -8/7);
    printf("-9/7 prints: %d\n", -9/7);
    printf("-11/8 prints: %d\n", -11/8);
    printf("-7/9 prints: %d\n", -7/9);
}
</bug.d>


output:

D:\Documents and Settings\Aljudy\temp>dmd bug
E:\dmd\dmd\bin\..\..\dm\bin\link.exe bug,,,user32+kernel32/noi;

D:\Documents and Settings\Aljudy\temp>bug
-5/3 prints: 1431655763
-5/2 prints: -3
-7/3 prints: 1431655763
-7/4 prints: -2
-7/7 prints: -1840700271
-8/7 prints: -1840700271
-9/7 prints: -1840700271
-11/8 prints: -2
-7/9 prints: 1908874353

>zwang wrote:
>> Hiroshi Sakurai wrote:
>> 
>>> Hi.
>>> This topic writen U in Japanese D Language Wiki.
>>> http://f17.aaa.livedoor.jp/~labamba/?BugTrack%2F19
>>>
>>> foo(-288*1000/360) is not -800.
>>>
>>>
>>>
>>> void main(char[][] arg) {
>>> printf("ok %d\n",  3/3);// 1
>>> printf("ok %d\n", -(3/3));// -1
>>>
>>> printf("ng %d\n", -3/3);// 1431655764
>>> int a = cast(int)(-3/3);
>>> printf("ng %d\n", a);// 1431655764
>>> printf("ng %d\n", (-3)/3);// 1431655764
>>> }
>>>
>>>
>> 
>> Already reported. See D.bugs:4750.
>
>but this is kind of different, it's not treated as positive (or atleast doesn't seem like that)
>
>funny thing is, -2/2 works fine!!
>and so does -3/1
>
>it's kind of odd .. in some cases it works, some cases it doesn't .. maybe an optamization bug?
>
><bug.d>
>void main(char[][] arg)
>{
>     printf("-5/3 prints: %d\n", -5/3);
>     printf("-5/2 prints: %d\n", -5/2);
>     printf("-7/3 prints: %d\n", -7/3);
>     printf("-7/4 prints: %d\n", -7/4);
>     printf("-7/7 prints: %d\n", -7/7);
>     printf("-8/7 prints: %d\n", -8/7);
>     printf("-9/7 prints: %d\n", -9/7);
>     printf("-11/8 prints: %d\n", -11/8);
>     printf("-7/9 prints: %d\n", -7/9);
>}
></bug.d>
>
>
>output:
>
>D:\Documents and Settings\Aljudy\temp>dmd bug E:\dmd\dmd\bin\..\..\dm\bin\link.exe bug,,,user32+kernel32/noi;
>
>D:\Documents and Settings\Aljudy\temp>bug
>-5/3 prints: 1431655763
>-5/2 prints: -3
>-7/3 prints: 1431655763
>-7/4 prints: -2
>-7/7 prints: -1840700271
>-8/7 prints: -1840700271
>-9/7 prints: -1840700271
>-11/8 prints: -2
>-7/9 prints: 1908874353

Thank you for having already taught what the bug has reported. I am not reading all Newsgroups. Therefore, I did not notice it.

I thought that it was interesting that -2/2 had moved well.
I also thought that it might have happened while the bug had optimized the code.


Hiroshi Sakurai.

Hiroshi Sakurai schrieb:

> Hi.
> This topic writen U in Japanese D Language Wiki.
> http://f17.aaa.livedoor.jp/~labamba/?BugTrack%2F19
> 
> foo(-288*1000/360) is not -800.
> 
> 
> 
> void main(char[][] arg) {
> printf("ok %d\n",  3/3);// 1
> printf("ok %d\n", -(3/3));// -1
> 
> printf("ng %d\n", -3/3);// 1431655764
> int a = cast(int)(-3/3);
> printf("ng %d\n", a);// 1431655764
> printf("ng %d\n", (-3)/3);// 1431655764
> }

Added to DStress as http://dstress.kuehne.cn/run/o/opDiv_10_A.d http://dstress.kuehne.cn/run/o/opDiv_10_B.d

Thomas