USUBOV            390 ext/uvector/uvector.c     USUBOV(r, v, x, y);
USUBOV            483 ext/uvector/uvector.c     USUBOV(r, v, x, y);
USUBOV            148 src/gauche/arith.h #ifndef USUBOV
USUBOV            234 src/test-arith.c     TESTOV(x_, y_, rexp, cexp, "%u", "-", USUBOV)