* spot/misc/bitset.cc, spot/misc/bitset.hh (set, clear): Turn asserts into exceptions. * spot/twa/acc.hh (mark_t): As a consequence, the constructor is not noexcept anymore. * tests/core/acc.cc, tests/python/except.py: More tests.
* spot/misc/bitset.hh: Here. * spot/misc/bitset.cc: New file. * spot/misc/Makefile.am: Add it. * spot/twa/acc.hh: Conditionally remove the exception checks around shift operators. * spot/misc/common.hh (SPOT_ASSUME): New macro.