With cc1 from PR24195, we have: ... $ ls -l cc1; for n in 1 2 3; do dwz -l50000000 cc1; ls -l cc1; done -rw-r--r-- 1 vries users 284381576 11 feb 14:13 cc1 -rw-r--r-- 1 vries users 233733176 11 feb 14:13 cc1 -rw-r--r-- 1 vries users 233729656 11 feb 14:13 cc1 ./dwz: cc1: DWARF compression not beneficial - old size 69207401 new size 69207678 -rw-r--r-- 1 vries users 233729656 11 feb 14:13 cc1 ... Ideally, we'd got to 233729656 in one dwz invocation.