On an iMac Pro (some Intel chip), the first failure (rings/polynomial/multi_polynomial_ideal.py) is also related to giac:
sage: A9=PolynomialRing(QQ,9,'x') ## line 4225 ##
sage: I9=sage.rings.ideal.Katsura(A9) ## line 4226 ##
sage: print("possible output from giac", flush=True); I9.groebner_basis("giac",proba_epsilon=1e-7) # long time (3s) ## line 4227 ##
possible output from giac
------------------------------------------------------------------------
0
signals.cpython-311-darwin.so 0x000000010edc1582 print_backtrace + 66
1
signals.cpython-311-darwin.so 0x000000010edc40b3 sigdie + 67
2
signals.cpython-311-darwin.so 0x000000010edc3fa9 cysigs_signal_handler + 505
3 libsystem_platform.dylib 0x00007ff81a2185ed _sigtramp + 29
4 ??? 0x0000000000000000 0x0 + 0
5 libgiac.0.dylib 0x00000001780b7e7e _ZN4giac10do_zbuildMINS_8tdeg_t14EEEvRKNS_12vectzpolymodIT_EERKNSt3__16vectorIjNS7_9allocatorIjEEEEibRKNS8_INS8_IS3_NS9_IS3_EEEENS9_ISF_EEEERKSF_RKNS8_IiNS9_IiEEEEPvRNS8_INS_12coeffindex_tENS9_ISR_EEEEjRNS8_INS8_ItNS9_ItEEEENS9_ISW_EEEERNS8_ISN_NS9_ISN_EEEERNS8_INS_14sparse_elementENS9_IS13_EEEEiii + 334
6 libgiac.0.dylib 0x00000001780b7d12 _ZN4giac8zbuildM_INS_8tdeg_t14EEEPvS2_ + 114
7 libsystem_pthread.dylib 0x00007ff81a1eb1d3 _pthread_start + 125
8 libsystem_pthread.dylib 0x00007ff81a1e6bd3 thread_start + 15
------------------------------------------------------------------------
Unhandled SIGSEGV during signal handling.
This probably occurred because a *compiled* module has a bug
in it and is not properly wrapped with sig_on(), sig_off().
Python will now terminate.
-----------------------------------------------
The second one (giac/__init__.py) times out. The log file says