Note that as recommended by John Regehr, author of C-Reduce, for this use case you might also want to try Shrinkray, a tool that was written to be format independent and works well for cases that C-Reduce dow not: https://mastodon.social/@regehr/113489759789563570
Is this[0] the official repo of Shrinkray?
Looking forward to try it! A shout out to cvise (https://github.com/marxin/cvise) as a python alternative that works well too for non c languages.