`fedora-37`: fflas_ffpack-2.5.0 fails to build (sporadic FFPACK::CharpolyFailed)

[mkoeppe]

minimal-pre / linux (fedora-37, minimal)

  [spkg-install] Threshold between CharPoly algorithms LUKrylov <-> ArithProg (using ModularBalanced<double> modulo 4194301)
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install] 
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install] Charpoly:  n                   LUKrylov                        ArithProg
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]                     seconds            Gfops          seconds            Gfops
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       1024         0.512493          5.65686          1.13681          2.55021
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       1152         0.768569          5.37079          1.30113          3.17249
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       1280         0.919617          6.15725          1.70431          3.32234
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       1408          1.22538          6.15035          2.13251          3.53412
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       1536          1.79558           5.4492          2.67383          3.65935
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       1664           2.3789          5.22935          3.16687           3.9282
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       1792          3.07645          5.05042          3.57053          4.35156
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       1920          3.55595          5.37417          2.81152          6.79713
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       1920          2.58591          7.39015          3.23279          5.91139
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       2048          3.25832          7.11804          3.25349          7.12861
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install]       2048          2.84461          8.15324          3.55221          6.52912
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install] terminate called after throwing an instance of 'FFPACK::CharpolyFailed'
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install] make[4]: *** [Makefile:977: autotune] Error 134
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install] make[3]: *** [Makefile:1005: autotune] Error 2
#24 6754.3   [fflas_ffpack-2.5.0]   [spkg-install] Error tuning fflas-ffpack

[vincentmacri]

Fedora 37 is past EOL so maybe dropping support for it should be added to #32074.

[mkoeppe]

Likely this failure here is not specific to fedora-37 but indicates some instability of the autotuning code.

[vbraun]

I've seen this before and retry worked as far as I remember

[mkoeppe]

Seen again (for fedora-37-standard) in https://github.com/sagemath/sage/actions/runs/9435864412/job/25989852570#step:11:6916