fix error

src/MagAlpha.cpp

@@ -0,0 +1,14 @@
+/***************************************************
+  Arduino library for the MPS MagAlpha magnetic angle sensor
+  Supports MagAlpha 3rd generation Sensors. MagAlpha sensor detects the
+  absolute angular position of a permanent magnet, typically a diametrically
+  magnetized cylinder on the rotating shaft.
+  ----> http://www.monolithicpower.com/Products/Position-Sensors/Products-Overview
+  Written by Mathieu Kaelin for Monolithic Power Systems.
+  MIT license, all text above must be included in any redistribution
+****************************************************/
+
+#include "MagAlpha.h"
+
+MagAlpha::MagAlpha(){
+}

src/MagAlpha.h

@@ -22,6 +22,10 @@
 #define MA_SPI_MODE_0       SPI_MODE0
 #define MA_SPI_MODE_3       SPI_MODE3
 
-class MagAlpha: public MagAlphaGen3 {};
+class MagAlpha: public MagAlphaGen3 {
+public:
+     MagAlpha();
+};
+
 
 #endif //MAGALPHA_H

src/MagAlphaGen3.h

@@ -50,6 +50,7 @@ class MagAlphaGen3: public MagAlphaSPI {
     uint8_t getSiliconId() override;
     uint8_t getSiliconRevision() override;
     uint8_t getRegisterMapRevision() override;
+};
 
 class MagAlphaSSIGen3: public MagAlphaSSI {};