From f845a8bb1a8bb560d4a4cbad71c2d559aeceb9b1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Antonio=20S=C3=A1nchez?= <cantonios@google.com>
Date: Sat, 16 Apr 2022 05:07:44 +0000
Subject: [PATCH] Fix cwise NaN propagation for scalar input.

---
 Eigen/src/plugins/MatrixCwiseBinaryOps.h | 6 +++---
 test/array_for_matrix.cpp                | 9 +++++++++
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/Eigen/src/plugins/MatrixCwiseBinaryOps.h b/Eigen/src/plugins/MatrixCwiseBinaryOps.h
index fa84c3cfc..46fe08ce8 100644
--- a/Eigen/src/plugins/MatrixCwiseBinaryOps.h
+++ b/Eigen/src/plugins/MatrixCwiseBinaryOps.h
@@ -86,10 +86,10 @@ cwiseMin(const EIGEN_CURRENT_STORAGE_BASE_CLASS<OtherDerived> &other) const
   */
 template<int NaNPropagation=PropagateFast>
 EIGEN_DEVICE_FUNC
-    EIGEN_STRONG_INLINE const CwiseBinaryOp<internal::scalar_min_op<Scalar,Scalar,NaNPropagation>, const Derived, const ConstantReturnType>
+EIGEN_STRONG_INLINE const CwiseBinaryOp<internal::scalar_min_op<Scalar,Scalar,NaNPropagation>, const Derived, const ConstantReturnType>
 cwiseMin(const Scalar &other) const
 {
-  return cwiseMin(Derived::Constant(rows(), cols(), other));
+  return cwiseMin<NaNPropagation>(Derived::Constant(rows(), cols(), other));
 }
 
 /** \returns an expression of the coefficient-wise max of *this and \a other
@@ -116,7 +116,7 @@ EIGEN_DEVICE_FUNC
 EIGEN_STRONG_INLINE const CwiseBinaryOp<internal::scalar_max_op<Scalar,Scalar,NaNPropagation>, const Derived, const ConstantReturnType>
 cwiseMax(const Scalar &other) const
 {
-  return cwiseMax(Derived::Constant(rows(), cols(), other));
+  return cwiseMax<NaNPropagation>(Derived::Constant(rows(), cols(), other));
 }
 
 
diff --git a/test/array_for_matrix.cpp b/test/array_for_matrix.cpp
index 8086b3432..06e04a2fa 100644
--- a/test/array_for_matrix.cpp
+++ b/test/array_for_matrix.cpp
@@ -219,11 +219,20 @@ template<typename MatrixType> void cwise_min_max(const MatrixType& m)
     VERIFY((numext::isnan)(m1.template cwiseMin<PropagateNaN>(MatrixType::Constant(rows,cols, Scalar(1)))(0,0)));
     VERIFY(!(numext::isnan)(m1.template cwiseMax<PropagateNumbers>(MatrixType::Constant(rows,cols, Scalar(1)))(0,0)));
     VERIFY(!(numext::isnan)(m1.template cwiseMin<PropagateNumbers>(MatrixType::Constant(rows,cols, Scalar(1)))(0,0)));
+    VERIFY((numext::isnan)(m1.template cwiseMax<PropagateNaN>(Scalar(1))(0,0)));
+    VERIFY((numext::isnan)(m1.template cwiseMin<PropagateNaN>(Scalar(1))(0,0)));
+    VERIFY(!(numext::isnan)(m1.template cwiseMax<PropagateNumbers>(Scalar(1))(0,0)));
+    VERIFY(!(numext::isnan)(m1.template cwiseMin<PropagateNumbers>(Scalar(1))(0,0)));
+
 
     VERIFY((numext::isnan)(m1.array().template max<PropagateNaN>(MatrixType::Constant(rows,cols, Scalar(1)).array())(0,0)));
     VERIFY((numext::isnan)(m1.array().template min<PropagateNaN>(MatrixType::Constant(rows,cols, Scalar(1)).array())(0,0)));
     VERIFY(!(numext::isnan)(m1.array().template max<PropagateNumbers>(MatrixType::Constant(rows,cols, Scalar(1)).array())(0,0)));
     VERIFY(!(numext::isnan)(m1.array().template min<PropagateNumbers>(MatrixType::Constant(rows,cols, Scalar(1)).array())(0,0)));
+    VERIFY((numext::isnan)(m1.array().template max<PropagateNaN>(Scalar(1))(0,0)));
+    VERIFY((numext::isnan)(m1.array().template min<PropagateNaN>(Scalar(1))(0,0)));
+    VERIFY(!(numext::isnan)(m1.array().template max<PropagateNumbers>(Scalar(1))(0,0)));
+    VERIFY(!(numext::isnan)(m1.array().template min<PropagateNumbers>(Scalar(1))(0,0)));
 
     // Reductions.
     VERIFY((numext::isnan)(m1.template maxCoeff<PropagateNaN>()));