diff --git a/ssh.h b/ssh.h
index 3bb8593b..2f4dd61c 100644
--- a/ssh.h
+++ b/ssh.h
@@ -104,7 +104,7 @@ struct ec_curve;
 struct ec_point {
     const struct ec_curve *curve;
     Bignum x, y;
-    Bignum z;  // Jacobian denominator
+    Bignum z;  /* Jacobian denominator */
     unsigned char infinity;
 };
 
diff --git a/sshecc.c b/sshecc.c
index 3c2d829f..7d877bad 100644
--- a/sshecc.c
+++ b/sshecc.c
@@ -511,17 +511,17 @@ static int ecp_normalise(struct ec_point *a)
     /* In Jacobian Coordinates the triple (X, Y, Z) represents
        the affine point (X / Z^2, Y / Z^3) */
     if (!a) {
-        // No point
+        /* No point */
         return 0;
     }
     if (a->infinity) {
-        // Point is at infinity - i.e. normalised
+        /* Point is at infinity - i.e. normalised */
         return 1;
     } else if (!a->x || !a->y) {
-        // No point defined
+        /* No point defined */
         return 0;
     } else if (!a->z) {
-        // Already normalised
+        /* Already normalised */
         return 1;
     }