Prefer std:: functions when available rather than non std functions

Allows to fix build on ubuntu 12.04 ci:
modules/core/src/math/misc/vpMath.cpp:181:24: error: ‘isfinite’ was not declared in this scope

modules/core/include/visp3/core/vpMath.h

@@ -324,12 +324,12 @@ long double vpMath::comb(unsigned int n, unsigned int p)
 */
 int vpMath::round(double x)
 {
-#if defined(VISP_HAVE_FUNC_ROUND)
+#if defined(VISP_HAVE_FUNC_STD_ROUND)
+  return (int)std::round(x);
+#elif defined(VISP_HAVE_FUNC_ROUND)
   //:: to design the global namespace and avoid to call recursively
   // vpMath::round
   return (int)::round(x);
-#elif defined(VISP_HAVE_FUNC_STD_ROUND)
-  return (int)std::round(x);
 #else
   return (x > 0.0) ? ((int)floor(x + 0.5)) : ((int)ceil(x - 0.5));
 #endif

modules/core/src/math/misc/vpMath.cpp

@@ -92,10 +92,10 @@ const double vpMath::ang_min_mc = 2.5e-4;
  */
 bool vpMath::isNaN(double value)
 {
-#if defined(VISP_HAVE_FUNC_ISNAN)
-  return isnan(value);
-#elif defined(VISP_HAVE_FUNC_STD_ISNAN)
+#if defined(VISP_HAVE_FUNC_STD_ISNAN)
   return std::isnan(value);
+#elif defined(VISP_HAVE_FUNC_ISNAN)
+  return isnan(value);
 #elif defined(VISP_HAVE_FUNC__ISNAN)
   return (_isnan(value) != 0);
 #else
@@ -113,10 +113,10 @@ bool vpMath::isNaN(double value)
  */
 bool vpMath::isNaN(float value)
 {
-#if defined(VISP_HAVE_FUNC_ISNAN)
-  return isnan(value);
-#elif defined(VISP_HAVE_FUNC_STD_ISNAN)
+#if defined(VISP_HAVE_FUNC_STD_ISNAN)
   return std::isnan(value);
+#elif defined(VISP_HAVE_FUNC_ISNAN)
+  return isnan(value);
 #elif defined(VISP_HAVE_FUNC__ISNAN)
   return (_isnan(value) != 0);
 #else
@@ -136,10 +136,10 @@ bool vpMath::isNaN(float value)
  */
 bool vpMath::isInf(double value)
 {
-#if defined(VISP_HAVE_FUNC_ISINF)
-  return isinf(value);
-#elif defined(VISP_HAVE_FUNC_STD_ISINF)
+#if defined(VISP_HAVE_FUNC_STD_ISINF)
   return std::isinf(value);
+#elif defined(VISP_HAVE_FUNC_ISINF)
+  return isinf(value);
 #else
   // Taken from OpenCV source code CvIsInf()
   Vp64suf ieee754;
@@ -157,10 +157,10 @@ bool vpMath::isInf(double value)
  */
 bool vpMath::isInf(float value)
 {
-#if defined(VISP_HAVE_FUNC_ISINF)
-  return isinf(value);
-#elif defined(VISP_HAVE_FUNC_STD_ISINF)
+#if defined(VISP_HAVE_FUNC_STD_ISINF)
   return std::isinf(value);
+#elif defined(VISP_HAVE_FUNC_ISINF)
+  return isinf(value);
 #else
   // Taken from OpenCV source code CvIsInf()
   Vp32suf ieee754;
@@ -177,10 +177,10 @@ bool vpMath::isInf(float value)
  */
 bool vpMath::isFinite(double value)
 {
-#if defined(VISP_HAVE_FUNC_ISFINITE)
-  return isfinite(value);
-#elif defined(VISP_HAVE_FUNC_STD_ISFINITE)
+#if defined(VISP_HAVE_FUNC_STD_ISFINITE)
   return std::isfinite(value);
+#elif defined(VISP_HAVE_FUNC_ISFINITE)
+  return isfinite(value);
 #elif defined(VISP_HAVE_FUNC__FINITE)
   return _finite(value);
 #else
@@ -196,10 +196,10 @@ bool vpMath::isFinite(double value)
  */
 bool vpMath::isFinite(float value)
 {
-#if defined(VISP_HAVE_FUNC_ISFINITE)
-  return isfinite(value);
-#elif defined(VISP_HAVE_FUNC_STD_ISFINITE)
+#if defined(VISP_HAVE_FUNC_STD_ISFINITE)
   return std::isfinite(value);
+#elif defined(VISP_HAVE_FUNC_ISFINITE)
+  return isfinite(value);
 #elif defined(VISP_HAVE_FUNC__FINITE)
   return _finitef(value);
 #else