(check_effective_target_pcc_bitfield_type_matters): New proc.
* gcc.dg/bitfld-3.c: Gate on target pcc_bitfield_type_matters.
+ PR testsuite/23304
* lib/target-supports.exp (check_effective_default_packed): New proc.
* g++.dg/ext/packed3.C, g++.dg/ext/packed8.C, g++.dg/other/crash-4.C:
Gate expected errors on target ! default_packed.