Bug#1121148: libobject-pad-perl: ftbfs on i386

[Emilio Pozuelo Monfort]

On Sun, 28 Dec 2025 20:15:45 +0200 Niko Tyni <ntyni at debian.org> wrote:
> Control: tag -1 patch
> 
> On Fri, Nov 21, 2025 at 10:02:39PM +0100, Paul Gevers wrote:
> > Source: libobject-pad-perl
> > Version: 0.821-1
> > Severity: serious
> > Justification: ftbfs
> > User: debian-qa at lists.debian.org
> > Usertags: i386
> > Control: -1 blocks 1118269
> 
> > The last upload of libobject-pad-perl failed to build on the buildds on
> > i386.
> 
> > # Failed test 'class scope with import version 0.821 does not imply use
> > strict'
> > # at t/51pragmata.t line 27.
> > # Code failed to compile - Global symbol "$def" requires explicit package
> > name (did you forget to declare "my $def"?) at (eval 21) line 3.
> > # Global symbol "$def" requires explicit package name (did you forget to
> > declare "my $def"?) at (eval 21) line 3.
> 
> Hi, this seems to be a floating point precision thing specific to i386.
> 
> The following C test program shows it:
> 
>   #include <stdlib.h>
>   #include <stdio.h>
>   int main(void) {
>   	double d = strtod("0.821", NULL);
>   	printf("int(%.25f * 1000) ==\nint(  %.28f) ==\n      %d\n", d, 1000 * d, (int)(1000 * d));
>   }
> 
> On amd64, the result is 821 as expected by the libobject-pad-perl code:
> 
>   int(0.8209999999999999520383653 * 1000) ==
>   int(  821.0000000000000000000000000000) ==
>         821
>  
> but in an i386 chroot on an amd64 host we get 820:
> 
>   int(0.8209999999999999520383653 * 1000) ==
>   int(  821.0000000000000000000000000000) ==
>         820
>  
> Not sure what to make of this, but the attached patch that applies
> round(3) before casting to integer fixes it for me. Hopefully #including
> <math.h> is acceptable upstream, but if not I'm sure they can come up
> with something better.

I found this [1] which seems related.

An upload would be appreciated as this is blocking the ongoing ocaml transition.

Cheers,
Emilio

[1] 
https://www.xatlantis.ch/index.php/blog/linux-programming/24-double-precision-error