add compatibility for standard C++ min/max

Author: Owen L - SFE

cores/arduino/ard_sup/Arduino_defines.h

@@ -28,8 +28,33 @@
 #undef abs
 #endif // abs
 
-#define min(a, b) ((a) < (b) ? (a) : (b))
-#define max(a, b) ((a) > (b) ? (a) : (b))
+#ifdef __cplusplus
+  template<class T, class L> 
+  auto min(const T& a, const L& b) -> decltype((b < a) ? b : a)
+  {
+    return (b < a) ? b : a;
+  }
+
+  template<class T, class L> 
+  auto max(const T& a, const L& b) -> decltype((b < a) ? b : a)
+  {
+    return (a < b) ? b : a;
+  }
+#else
+#ifndef min
+#define min(a,b) \
+   ({ __typeof__ (a) _a = (a); \
+       __typeof__ (b) _b = (b); \
+     _a < _b ? _a : _b; })
+#endif
+#ifndef max
+#define max(a,b) \
+   ({ __typeof__ (a) _a = (a); \
+       __typeof__ (b) _b = (b); \
+     _a > _b ? _a : _b; })
+#endif
+#endif
+
 #define abs(x) ((x) > 0 ? (x) : -(x))
 #define constrain(amt, low, high) ((amt) < (low) ? (low) : ((amt) > (high) ? (high) : (amt)))
 #define round(x) ((x) >= 0 ? (long)((x) + 0.5) : (long)((x)-0.5))