diff --git a/Eigen/src/Core/arch/Default/GenericPacketMathFunctions.h b/Eigen/src/Core/arch/Default/GenericPacketMathFunctions.h
index 22f6fb977..a0e5f9fef 100644
--- a/Eigen/src/Core/arch/Default/GenericPacketMathFunctions.h
+++ b/Eigen/src/Core/arch/Default/GenericPacketMathFunctions.h
@@ -921,9 +921,9 @@ Packet patan_double(const Packet& x_in) {
   static_assert(std::is_same<Scalar, double>::value, "Scalar type must be double");
 
   const Packet cst_one = pset1<Packet>(1.0);
-  constexpr double kPiOverTwo = static_cast<double>(M_PI_2);
+  constexpr double kPiOverTwo = static_cast<double>(EIGEN_PI / 2);
   const Packet cst_pi_over_two = pset1<Packet>(kPiOverTwo);
-  constexpr double kPiOverFour = static_cast<double>(M_PI_4);
+  constexpr double kPiOverFour = static_cast<double>(EIGEN_PI / 4);
   const Packet cst_pi_over_four = pset1<Packet>(kPiOverFour);
   const Packet cst_large = pset1<Packet>(2.4142135623730950488016887);  // tan(3*pi/8);
   const Packet cst_medium = pset1<Packet>(0.4142135623730950488016887);  // tan(pi/8);
diff --git a/Eigen/src/Core/functors/BinaryFunctors.h b/Eigen/src/Core/functors/BinaryFunctors.h
index ee568ecf6..2169c1e4e 100644
--- a/Eigen/src/Core/functors/BinaryFunctors.h
+++ b/Eigen/src/Core/functors/BinaryFunctors.h
@@ -523,11 +523,11 @@ struct scalar_atan2_op {
     // See https://en.cppreference.com/w/cpp/numeric/math/atan2
     // for how corner cases are supposed to be handles according to the
     // IEEE floating-point standard (IEC 60559).
-    constexpr Scalar k3PiO3f = Scalar(3.0 * M_PI_4);
+    constexpr Scalar k3PiO3f = Scalar(3 * (EIGEN_PI / 4));
     const Packet kSignMask = pset1<Packet>(Scalar(-0.0));
     const Packet kPi = pset1<Packet>(Scalar(EIGEN_PI));
-    const Packet kPiO2 = pset1<Packet>(Scalar(M_PI_2));
-    const Packet kPiO4 = pset1<Packet>(Scalar(M_PI_4));
+    const Packet kPiO2 = pset1<Packet>(Scalar(EIGEN_PI / 2));
+    const Packet kPiO4 = pset1<Packet>(Scalar(EIGEN_PI / 4));
     const Packet k3PiO4 = pset1<Packet>(k3PiO3f);
     Packet x_neg = pcmp_lt(x, pzero(x));
     Packet x_sign = pand(x, kSignMask);
@@ -554,7 +554,6 @@ struct scalar_atan2_op {
     result = pselect(y_zero,
                      pselect(x_sign, por(y_sign, kPi), por(y_sign, pzero(y))),
                      result);
-
     return result;
   }
 };