From 8972323c088350200fd9e799238081aa37c2342a Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Wed, 27 Jul 2016 14:52:48 +0200
Subject: [PATCH] Big 1261: add missing max(ADS,ADS) overload (same for min)

---
 unsupported/Eigen/src/AutoDiff/AutoDiffScalar.h |  9 +++++++++
 unsupported/test/autodiff.cpp                   | 12 ++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/unsupported/Eigen/src/AutoDiff/AutoDiffScalar.h b/unsupported/Eigen/src/AutoDiff/AutoDiffScalar.h
index 98e0e3b73..2db4d8c3b 100755
--- a/unsupported/Eigen/src/AutoDiff/AutoDiffScalar.h
+++ b/unsupported/Eigen/src/AutoDiff/AutoDiffScalar.h
@@ -562,6 +562,15 @@ inline AutoDiffScalar<typename Eigen::internal::remove_all<DerType>::type::Plain
   typedef AutoDiffScalar<typename Eigen::internal::remove_all<DerType>::type::PlainObject> ADS;
   return (x > y ? ADS(x) : ADS(y));
 }
+template<typename DerType>
+inline AutoDiffScalar<typename Eigen::internal::remove_all<DerType>::type::PlainObject> (min)(const AutoDiffScalar<DerType>& x, const AutoDiffScalar<DerType>& y) {
+  return (x.value() < y.value() ? x : y);
+}
+template<typename DerType>
+inline AutoDiffScalar<typename Eigen::internal::remove_all<DerType>::type::PlainObject> (max)(const AutoDiffScalar<DerType>& x, const AutoDiffScalar<DerType>& y) {
+  return (x.value() >= y.value() ? x : y);
+}
+
 
 EIGEN_AUTODIFF_DECLARE_GLOBAL_UNARY(abs,
   using std::abs;
diff --git a/unsupported/test/autodiff.cpp b/unsupported/test/autodiff.cpp
index 83f336d68..118cf2ec7 100644
--- a/unsupported/test/autodiff.cpp
+++ b/unsupported/test/autodiff.cpp
@@ -245,6 +245,17 @@ void bug_1260() {
   A*v;
 }
 
+// check a compilation issue with numext::max
+double bug_1261() {
+  typedef AutoDiffScalar<Matrix2d> AD;
+  typedef Matrix<AD,2,1> VectorAD;
+
+  VectorAD v;
+  const AD maxVal = v.maxCoeff();
+  const AD minVal = v.minCoeff();
+  return maxVal.value() + minVal.value();
+}
+
 void test_autodiff()
 {
   for(int i = 0; i < g_repeat; i++) {
@@ -257,5 +268,6 @@ void test_autodiff()
   bug_1222();
   bug_1223();
   bug_1260();
+  bug_1261();
 }