diff --git a/src/gcd.cpp b/src/gcd.cpp
index 46a515c..1b8d997 100644
--- a/src/gcd.cpp
+++ b/src/gcd.cpp
@@ -1,5 +1,10 @@
 #include "cheapr_cpp.h"
 
+
+template<typename T> T cpp_sign(T x) {
+  return (x > 0) - (x < 0);
+}
+
 [[cpp11::register]]
 double cpp_gcd2(double x, double y, double tol, bool na_rm){
   double zero = 0.0;
@@ -127,7 +132,7 @@ SEXP cpp_gcd(SEXP x, double tol, bool na_rm, bool break_early, bool round){
         break;
       }
       if (break_early && agcd > 0.0 && agcd < (tol + tol)){
-        gcd = tol * ( (gcd > 0) - (gcd < 0)); // tol * sign(gcd)
+        gcd = tol * cpp_sign<double>(gcd);
         break;
       }
     }
diff --git a/src/lag.cpp b/src/lag.cpp
index 578825d..748d22c 100644
--- a/src/lag.cpp
+++ b/src/lag.cpp
@@ -1,10 +1,4 @@
 #include "cheapr_cpp.h"
-#include <variant>
-#include <memory>
-
-template<typename T> T cpp_sign(T x) {
-  return (x > 0) - (x < 0);
-}
 
 // Internal fast check for valid order values (here they are 0-indexed)
 // Where rng = length(x) - 1