#define _XBT_LOG_CONCAT(x, y) x ## y
#define _XBT_LOG_CONCAT2(x, y) _XBT_LOG_CONCAT(x, y)
/* Apparently, constructor priorities are not supported by gcc on Macs */
-#if __GNUC__ && __APPLE__
+#if defined(__GNUC__) && defined(__APPLE__)
# define _XBT_LOGV_CTOR_ATTRIBUTE
#else
# define _XBT_LOGV_CTOR_ATTRIBUTE _XBT_GNUC_CONSTRUCTOR(600)