Guile 3.0.7 test failures on i686-linux, glibc 2.33 [core-updates]

On current ‘core-updates’

(ca. 39f1486efd70712416ca784f9014132644b04155), Guile 3.0.7,

specifically (@@ (gnu packages commencement) guile-final) fails tests on

i686-linux:

Note that this doesn’t happen on ‘master’ (glibc 3.31).

Ludo’.

severity 49368 important

quit

Ludovic Courtès schreef op za 03-07-2021 om 23:41 [+0200]:

In a REPL:

(euclidean/ 130.0 10/7)

(euclidean/ 130.0 -10/7)

(floor/ 130.0 10/7)

(floor/ -130.0 -10/7)

(ceiling/ 130.0 -10/7)

(ceiling/ -130.0 10/7)

(truncate/ 130.0 10/7)

(truncate/ 130.0 -10/7)

(truncate/ -130.0 10/7)

(truncate/ -130.0 -10/7)

Output on core-updates (using --keep-failed and ./meta/uninstalled-env guile):

scheme@(guile-user)> (euclidean/ 130.0 10/7)

$1 = 90.0

$2 = 1.4285714285714257

scheme@(guile-user)> (euclidean/ 130.0 -10/7)

$3 = -90.0

$4 = 1.4285714285714257

scheme@(guile-user)> (floor/ 130.0 10/7)

$5 = 90.0

$6 = 1.4285714285714257

scheme@(guile-user)> (floor/ -130.0 -10/7)

$7 = 90.0

$8 = -1.4285714285714257

scheme@(guile-user)> (ceiling/ 130.0 -10/7)

$9 = -90.0

$10 = 1.4285714285714257

scheme@(guile-user)> (ceiling/ -130.0 10/7)

$11 = -90.0

$12 = -1.4285714285714257

scheme@(guile-user)> (truncate/ 130.0 10/7)

$13 = 90.0

$14 = 1.4285714285714257

scheme@(guile-user)> (truncate/ 130.0 -10/7)

$15 = -90.0

$16 = 1.4285714285714257

scheme@(guile-user)> (truncate/ -130.0 10/7)

$17 = -90.0

$18 = -1.4285714285714257

scheme@(guile-user)> (truncate/ -130.0 -10/7)

$19 = 90.0

$20 = -1.4285714285714257

It appears that truncate/, ceiling/ and floor/ give the same output ...

that doesn't seem correct.

Greetings,

Maxime.

Ludovic Courtès schreef op za 03-07-2021 om 23:41 [+0200]:

Curiously, on core-updates, ceiling/ is inconsistent with ceiling-quotient

and ceiling-remainder:

scheme@(guile-user) [1]> (ceiling/ 130.0 -10/7)

$28 = -90.0

$29 = 1.4285714285714257

scheme@(guile-user) [1]> (ceiling-quotient 130.0 -10/7)

$30 = -91.0

scheme@(guile-user) [1]> (ceiling-remainder 130.0 -10/7)

$31 = 0.0

But on 'master', the results are consistent:

scheme@(guile-user)> (ceiling/ 130.0 -10/7)

$1 = -91.0

$2 = 0.0

scheme@(guile-user)> (ceiling-quotient 130.0 -10/7)

$3 = -91.0

scheme@(guile-user)> (ceiling-remainder 130.0 -10/7)

$4 = 0.0

To be investigated ...

Greetings,

Maxime.

Ludovic Courtès schreef op za 03-07-2021 om 23:41 [+0200]:

I wondered if the implementation of the C function 'ceil' is buggy,

so I tried the following (spoiler: 'ceil' doesn't seem to be the issue,

or I need another test case:

Run "guix build --system=i686-linux -e (@@ (gnu packages commencement) guile-final) --keep-failed".

In the build directory, write to a file "test.c":

#include <stdio.h>

#include <math.h>

int

main(void)

{

double x;

double y;

if (scanf("%lf %lf", &x, &y) < 0) /* < 0 is actually incorrect here */

return 1;

if (printf("%lf/%lf=%lf\n", x,y, x/y) < 0)

return 1;

if (printf("ceil(%lf/%lf)=%lf\n", x,y, ceil(x/y)) < 0)

return 1;

return 0;

}

Run ((exact->inexact 10/7) = 1.4285714285714286 on both master and core-updates):

$ gcc -Wall -Wextra -lm test.c -o test

$ echo "130.0 1.4285714285714286" | ./test

130.000000/1.428571=91.000000

ceil(130.000000/1.428571)=91.000000

On master, the output is:

130.000000/1.428571=91.000000

ceil(130.000000/1.428571)=91.000000

(idem)

Greetings,

Maxime.

Ludovic Courtès schreef op za 03-07-2021 om 23:41 [+0200]:

This has been fixed on core-updates:

Closing.

Greetings,

Maxime