Re: New math test failures on Fedora/33

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

On 11/01/2021 15:37, H.J. Lu wrote:
> On Mon, Jan 11, 2021 at 8:28 AM Adhemerval Zanella
> <adhemerval.zanella@linaro.org> wrote:
>>
>>
>>
>> On 11/01/2021 13:00, H.J. Lu via Libc-alpha wrote:
>>> On Fedora 33, I got these new math test failures:
>>>
>>> FAIL: math/test-double-cosh
>>> FAIL: math/test-float32x-cosh
>>> FAIL: math/test-float64-cosh
>>>
>>> for i686 glibc like
>>>
>>> Failure: cosh_upward (-0x2.c5d374p+12): Exception "Overflow" not set
>>> Failure: cosh_upward (-0x2.c5d37700c6bb2p+12): Exception "Overflow" not set
>>> Failure: cosh_upward (-0x2.c5d37700c6bbp+12): Exception "Overflow" not set
>>> Failure: cosh_upward (-0x2.c5d378p+12): Exception "Overflow" not set
>>> Failure: cosh_upward (-0x2.c679d1f73f0fcp+8): Exception "Overflow" not set
>>> Failure: cosh_upward (-0x2.c679d4p+8): Exception "Overflow" not set
>>> Failure: cosh_upward (-0xf.ffffffffffff8p+1020): Exception "Overflow" not set
>>> Failure: cosh_upward (-0xf.fffffp+124): Exception "Overflow" not set
>>> Failure: cosh_upward (0x2.c5d374p+12): Exception "Overflow" not set
>>> Failure: cosh_upward (0x2.c5d37700c6bb2p+12): Exception "Overflow" not set
>>> Failure: cosh_upward (0x2.c5d37700c6bbp+12): Exception "Overflow" not set
>>> Failure: cosh_upward (0x2.c5d378p+12): Exception "Overflow" not set
>>> Failure: cosh_upward (0x2.c679d1f73f0fcp+8): Exception "Overflow" not set
>>> Failure: cosh_upward (0x2.c679d4p+8): Exception "Overflow" not set
>>> Failure: cosh_upward (0xf.ffffffffffff8p+1020): Exception "Overflow" not set
>>> Failure: cosh_upward (0xf.fffffp+124): Exception "Overflow" not set
>>
>> This is a regression of BZ#18980 caused by 9e97f239eae1f2b1.  The original
>> issue was fixed by c8235dda728c445, but the patch did not add the fix for
>> wordsize64 version because it does not require back then (since it seems
>> to happen on 32-bit, at least I am seeing on i686).
>>
>> This seems to fix it:
>>
>> diff --git a/sysdeps/ieee754/dbl-64/e_cosh.c b/sysdeps/ieee754/dbl-64/e_cosh.c
>> index 4f41ca2c92..81de5ae6bd 100644
>> --- a/sysdeps/ieee754/dbl-64/e_cosh.c
>> +++ b/sysdeps/ieee754/dbl-64/e_cosh.c
>> @@ -33,6 +33,7 @@
>>
>>  #include <math.h>
>>  #include <math_private.h>
>> +#include <math-narrow-eval.h>
>>  #include <libm-alias-finite.h>
>>
>>  static const double one = 1.0, half=0.5, huge = 1.0e300;
>> @@ -80,6 +81,6 @@ __ieee754_cosh (double x)
>>         if(ix>=0x7ff00000) return x*x;
>>
>>      /* |x| > overflowthresold, cosh(x) overflow */
>> -       return huge*huge;
>> +       return math_narrow_eval (huge * huge);
>>  }
>>  libm_alias_finite (__ieee754_cosh, __cosh)
> 
> It fixed i686.  Can you check it in?

I will do it.

> 
> BTW, I also saw random failure:
> 
> FAIL: misc/tst-bz21269
> [hjl@gnu-skx-1 build-i686-linux]$ cat misc/tst-bz21269.out
> Timed out: killed the child process
> Termination time: 2021-01-11T18:13:03.494991075
> Last write to standard output: 2021-01-11T18:12:43.491654736
> [hjl@gnu-skx-1 build-i686-linux]$
> 
> Is this a known issue?

No I am aware, this tests is based on the kernel one
tools/testing/selftests/x86/ldt_gdt.c (more specifically the
do_multicpu_tests subtest) and the only difference seems kernel
one forces the sched_affinity.