msvc

src/utils/math.h

@@ -6,11 +6,7 @@
  * \author Tianqi Chen
  */
 #include <cmath>
-#ifdef _MSC_VER
-extern "C" {
-#include <amp_math.h>
-}
-#endif
+
 namespace xgboost {
 namespace utils {
 #ifdef XGBOOST_STRICT_CXX98_
@@ -21,14 +17,24 @@ double LogGamma(double v);
 template<typename T>
 inline bool CheckNAN(T v) {
 #ifdef _MSC_VER
-  return (_isnan(x) != 0);
+  return (_isnan(v) != 0);
 #else
   return isnan(v);
 #endif
 }
 template<typename T>
 inline T LogGamma(T v) {
+#ifdef _MSC_VER
+#if _MSC_VER >= 1800
   return lgamma(v);
+#else
+#pragma message ("Warning: lgamma function was not available until VS2013, poisson regression will be disabled")
+  utils::Error("lgamma function was not available until VS2013");
+  return static_cast<T>(1.0);
+#endif
+#else
+  return lgamma(v);
+#endif
 }
 #endif
 }  // namespace utils