Comment 5 for bug 1907472

I've observed the failure in the i386 build of glibc_2.33-0ubuntu4:

Linux lcy01-amd64-014 4.15.0-136-generic #140-Ubuntu SMP Thu Jan 28 05:20:47 UTC 2021 i686 athlon i686 GNU/Linux
...
if [ -f /proc/cpuinfo ] ; then cat /proc/cpuinfo ; fi
processor : 0
vendor_id : AuthenticAMD
cpu family : 16
model : 2
model name : AMD Opteron 23xx (Gen 3 Class Opteron)
stepping : 3
microcode : 0x1000065
cpu MHz : 2500.048
cache size : 512 KB
physical id : 0
siblings : 1
core id : 0
cpu cores : 1
apicid : 0
initial apicid : 0
fpu : yes
fpu_exception : yes
cpuid level : 5
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 syscall nx mmxext fxsr_opt pdpe1gb lm 3dnowext 3dnow rep_good nopl cpuid extd_apicid tsc_known_freq pni cx16 x2apic popcnt hypervisor lahf_lm cmp_legacy svm cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw vmmcall
bugs : tlb_mmatch fxsave_leak sysret_ss_attrs null_seg spectre_v1 spectre_v2
bogomips : 5000.09
TLB size : 1024 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 40 bits physical, 48 bits virtual
power management:
...

+---------------------------------------------------------------------+
| Encountered regressions that don't match expected failures. |
+---------------------------------------------------------------------+
FAIL: math/test-double-libmvec-sincos
FAIL: math/test-double-vlen2-sincos
FAIL: math/test-float-libmvec-sincosf
FAIL: math/test-float-vlen4-sincos
touch /<<PKGBUILDDIR>>/stamp-dir/check_x32
CHECK SUMMARY
check for check_libc passed
check for check_amd64 passed
check for check_x32 failed