From 1395056fc0c077b0a1e9b1854c6f18d6bbb9ee61 Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Fri, 20 May 2016 14:58:19 +0200
Subject: [PATCH] Make EIGEN_HAS_C99_MATH user configurable

---
 Eigen/src/Core/SpecialFunctions.h | 12 ++++++------
 Eigen/src/Core/arch/CUDA/Half.h   |  2 +-
 Eigen/src/Core/util/Macros.h      |  6 +++++-
 test/array.cpp                    |  6 +++---
 test/packetmath.cpp               |  4 ++--
 5 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/Eigen/src/Core/SpecialFunctions.h b/Eigen/src/Core/SpecialFunctions.h
index 4cf58c510..f34c7bcda 100644
--- a/Eigen/src/Core/SpecialFunctions.h
+++ b/Eigen/src/Core/SpecialFunctions.h
@@ -116,7 +116,7 @@ struct lgamma_retval {
   typedef Scalar type;
 };
 
-#ifdef EIGEN_HAS_C99_MATH
+#if EIGEN_HAS_C99_MATH
 template <>
 struct lgamma_impl<float> {
   EIGEN_DEVICE_FUNC
@@ -336,7 +336,7 @@ struct erf_retval {
   typedef Scalar type;
 };
 
-#ifdef EIGEN_HAS_C99_MATH
+#if EIGEN_HAS_C99_MATH
 template <>
 struct erf_impl<float> {
   EIGEN_DEVICE_FUNC
@@ -369,7 +369,7 @@ struct erfc_retval {
   typedef Scalar type;
 };
 
-#ifdef EIGEN_HAS_C99_MATH
+#if EIGEN_HAS_C99_MATH
 template <>
 struct erfc_impl<float> {
   EIGEN_DEVICE_FUNC
@@ -426,7 +426,7 @@ struct igamma_helper<double> {
   }
 };
 
-#ifndef EIGEN_HAS_C99_MATH
+#if !EIGEN_HAS_C99_MATH
 
 template <typename Scalar>
 struct igammac_impl {
@@ -608,7 +608,7 @@ struct igamma_retval {
   typedef Scalar type;
 };
 
-#ifndef EIGEN_HAS_C99_MATH
+#if !EIGEN_HAS_C99_MATH
 
 template <typename Scalar>
 struct igamma_impl {
@@ -967,7 +967,7 @@ struct polygamma_retval {
     typedef Scalar type;
 };
     
-#ifndef EIGEN_HAS_C99_MATH
+#if !EIGEN_HAS_C99_MATH
     
 template <typename Scalar>
 struct polygamma_impl {
diff --git a/Eigen/src/Core/arch/CUDA/Half.h b/Eigen/src/Core/arch/CUDA/Half.h
index 3ead82829..d081c7392 100644
--- a/Eigen/src/Core/arch/CUDA/Half.h
+++ b/Eigen/src/Core/arch/CUDA/Half.h
@@ -466,7 +466,7 @@ template <> EIGEN_STRONG_INLINE EIGEN_DEVICE_FUNC Eigen::half maxi(const Eigen::
 #endif
 }
 
-#ifdef EIGEN_HAS_C99_MATH
+#if EIGEN_HAS_C99_MATH
 template<> EIGEN_STRONG_INLINE EIGEN_DEVICE_FUNC Eigen::half lgamma(const Eigen::half& a) {
   return Eigen::half(Eigen::numext::lgamma(static_cast<float>(a)));
 }
diff --git a/Eigen/src/Core/util/Macros.h b/Eigen/src/Core/util/Macros.h
index 7fb194a40..3fcef82b6 100644
--- a/Eigen/src/Core/util/Macros.h
+++ b/Eigen/src/Core/util/Macros.h
@@ -360,11 +360,15 @@
 #endif
 
 // Does the compiler support C99?
+#ifndef EIGEN_HAS_C99_MATH
 #if EIGEN_MAX_CPP_VER>=11 && \
     ((defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901))       \
   || (defined(__GNUC__) && defined(_GLIBCXX_USE_C99)) \
   || (defined(_LIBCPP_VERSION) && !defined(_MSC_VER)))
-#define EIGEN_HAS_C99_MATH 1
+  #define EIGEN_HAS_C99_MATH 1
+#else
+  #define EIGEN_HAS_C99_MATH 0
+#endif
 #endif
 
 // Does the compiler support result_of?
diff --git a/test/array.cpp b/test/array.cpp
index ed81b0069..a028c7528 100644
--- a/test/array.cpp
+++ b/test/array.cpp
@@ -217,7 +217,7 @@ template<typename ArrayType> void array_real(const ArrayType& m)
   VERIFY_IS_APPROX(m1.sinh(), sinh(m1));
   VERIFY_IS_APPROX(m1.cosh(), cosh(m1));
   VERIFY_IS_APPROX(m1.tanh(), tanh(m1));
-#ifdef EIGEN_HAS_C99_MATH
+#if EIGEN_HAS_C99_MATH
   VERIFY_IS_APPROX(m1.lgamma(), lgamma(m1));
   VERIFY_IS_APPROX(m1.digamma(), digamma(m1));
   VERIFY_IS_APPROX(m1.erf(), erf(m1));
@@ -312,7 +312,7 @@ template<typename ArrayType> void array_real(const ArrayType& m)
 
 
 
-#ifdef EIGEN_HAS_C99_MATH
+#if EIGEN_HAS_C99_MATH
   // check special functions (comparing against numpy implementation)
   if (!NumTraits<Scalar>::IsComplex)
   {
@@ -582,7 +582,7 @@ template<typename ArrayType> void array_special_functions()
   }
 
 
-#ifdef EIGEN_HAS_C99_MATH
+#if EIGEN_HAS_C99_MATH
   {
     ArrayType n(11), x(11), res(11), ref(11);
     n << 1, 1,    1, 1.5,   17,   31,   28,    8, 42, 147, 170;
diff --git a/test/packetmath.cpp b/test/packetmath.cpp
index 0d96d614e..3e4eb1414 100644
--- a/test/packetmath.cpp
+++ b/test/packetmath.cpp
@@ -367,7 +367,7 @@ template<typename Scalar> void packetmath_real()
     VERIFY((numext::isnan)(data2[0]));
   }
 
-#ifdef EIGEN_HAS_C99_MATH
+#if EIGEN_HAS_C99_MATH
   {
     data1[0] = std::numeric_limits<Scalar>::quiet_NaN();
     packet_helper<internal::packet_traits<Scalar>::HasLGamma,Packet> h;
@@ -398,7 +398,7 @@ template<typename Scalar> void packetmath_real()
     data1[internal::random<int>(0, PacketSize)] = 0;
   CHECK_CWISE1_IF(PacketTraits::HasSqrt, std::sqrt, internal::psqrt);
   CHECK_CWISE1_IF(PacketTraits::HasLog, std::log, internal::plog);
-#if defined(EIGEN_HAS_C99_MATH) && (__cplusplus > 199711L)
+#if EIGEN_HAS_C99_MATH && (__cplusplus > 199711L)
   CHECK_CWISE1_IF(internal::packet_traits<Scalar>::HasLGamma, std::lgamma, internal::plgamma);
   CHECK_CWISE1_IF(internal::packet_traits<Scalar>::HasErf, std::erf, internal::perf);
   CHECK_CWISE1_IF(internal::packet_traits<Scalar>::HasErfc, std::erfc, internal::perfc);