diff --git a/src/win32_joystick.c b/src/win32_joystick.c
index 43336a31..0268e051 100644
--- a/src/win32_joystick.c
+++ b/src/win32_joystick.c
@@ -603,9 +603,9 @@ static GLFWbool pollJoystickState(_GLFWjoystickWin32* js, int mode)
         if (mode == _GLFW_PRESENCE_ONLY)
             return GLFW_TRUE;
 
-        if (sqrtf((float) (xis.Gamepad.sThumbLX * xis.Gamepad.sThumbLX +
+        if (sqrt((double) (xis.Gamepad.sThumbLX * xis.Gamepad.sThumbLX +
                            xis.Gamepad.sThumbLY * xis.Gamepad.sThumbLY)) >
-            (float) XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE)
+            (double) XINPUT_GAMEPAD_LEFT_THUMB_DEADZONE)
         {
             js->axes[0] = (xis.Gamepad.sThumbLX + 0.5f) / 32767.f;
             js->axes[1] = (xis.Gamepad.sThumbLY + 0.5f) / 32767.f;
@@ -616,9 +616,9 @@ static GLFWbool pollJoystickState(_GLFWjoystickWin32* js, int mode)
             js->axes[1] = 0.f;
         }
 
-        if (sqrtf((float) (xis.Gamepad.sThumbRX * xis.Gamepad.sThumbRX +
+        if (sqrt((double) (xis.Gamepad.sThumbRX * xis.Gamepad.sThumbRX +
                            xis.Gamepad.sThumbRY * xis.Gamepad.sThumbRY)) >
-            (float) XINPUT_GAMEPAD_RIGHT_THUMB_DEADZONE)
+            (double) XINPUT_GAMEPAD_RIGHT_THUMB_DEADZONE)
         {
             js->axes[2] = (xis.Gamepad.sThumbRX + 0.5f) / 32767.f;
             js->axes[3] = (xis.Gamepad.sThumbRY + 0.5f) / 32767.f;
diff --git a/src/win32_platform.h b/src/win32_platform.h
index d0dac96d..d44ca3b9 100644
--- a/src/win32_platform.h
+++ b/src/win32_platform.h
@@ -64,6 +64,7 @@
 // GLFW uses DirectInput8 interfaces
 #define DIRECTINPUT_VERSION 0x0800
 
+#include <wctype.h>
 #include <windows.h>
 #include <mmsystem.h>
 #include <dinput.h>