--- a/handler.cc
+++ b/handler.cc
@@ -23,6 +23,8 @@
 #include <X11/extensions/XTest.h>
 #include <X11/XKBlib.h>
 #include <X11/Xproto.h>
+#include <cmath>  // std::abs(float)
+using std::abs;
 
 XState *xstate = NULL;
 
@@ -533,8 +535,6 @@ class WaitForPongHandler : public Handler, protected Timeout {
 	virtual Grabber::State grab_mode() { return parent->grab_mode(); }
 };
 
-static inline float abs(float x) { return x > 0 ? x : -x; }
-
 class AbstractScrollHandler : public Handler {
 	bool have_x, have_y;
 	float last_x, last_y;