diff --git a/src/math/fdim.c b/src/math/fdim.c
index c3177de..c5680cc 100644
--- a/src/math/fdim.c
+++ b/src/math/fdim.c
@@ -32,7 +32,7 @@ int main(void)
 			err++;
 		}
 		d = ulperr(y, p->y, p->dy);
-		if (!checkulp(d, p->r)) {
+		if (!checkcr(y, p->y, p->r)) {
 			printf("%s:%d: %s fdim(%a,%a) want %a got %a ulperr %.3f = %a + %a\n",
 				p->file, p->line, rstr(p->r), p->x, p->x2, p->y, y, d, d-p->dy, p->dy);
 			err++;
diff --git a/src/math/fdimf.c b/src/math/fdimf.c
index 56dac2f..d7792bf 100644
--- a/src/math/fdimf.c
+++ b/src/math/fdimf.c
@@ -32,7 +32,7 @@ int main(void)
 			err++;
 		}
 		d = ulperrf(y, p->y, p->dy);
-		if (!checkulp(d, p->r)) {
+		if (!checkcr(y, p->y, p->r)) {
 			printf("%s:%d: %s fdimf(%a,%a) want %a got %a ulperr %.3f = %a + %a\n",
 				p->file, p->line, rstr(p->r), p->x, p->x2, p->y, y, d, d-p->dy, p->dy);
 			err++;
diff --git a/src/math/fdiml.c b/src/math/fdiml.c
index 9f07940..9f6eb95 100644
--- a/src/math/fdiml.c
+++ b/src/math/fdiml.c
@@ -37,7 +37,7 @@ int main(void)
 			err++;
 		}
 		d = ulperrl(y, p->y, p->dy);
-		if (!checkulp(d, p->r)) {
+		if (!checkcr(y, p->y, p->r)) {
 			printf("%s:%d: %s fdiml(%La,%La) want %La got %La ulperr %.3f = %a + %a\n",
 				p->file, p->line, rstr(p->r), p->x, p->x2, p->y, y, d, d-p->dy, p->dy);
 			err++;