bug #1223: fix compilation of AutoDiffScalar's min/max operators, and add regression unit test.

1 files changed, 19 insertions, 0 deletions

diff --git a/unsupported/test/autodiff.cpp b/unsupported/test/autodiff.cpp
index ad3f83d4e..b59fd1c43 100644
--- a/unsupported/test/autodiff.cpp
+++ b/unsupported/test/autodiff.cpp
@@ -216,6 +216,24 @@ double bug_1222() {
   return denom.value();
 }
 
+double bug_1223() {
+  using std::min;
+  typedef Eigen::AutoDiffScalar<Eigen::Vector3d> AD;
+
+  const double _cv1_3 = 1.0;
+  const AD chi_3 = 1.0;
+  const AD denom = 1.0;
+
+  // failed because implementation of min attempts to construct ADS<DerType&> via constructor AutoDiffScalar(const Real& value)
+  // without initializing m_derivatives (which is a reference in this case)
+  #define EIGEN_TEST_SPACE
+  const AD t = min EIGEN_TEST_SPACE (denom / chi_3, 1.0);
+
+  const AD t2 = min EIGEN_TEST_SPACE (denom / (chi_3 * _cv1_3), 1.0);
+
+  return t.value() + t2.value();
+}
+
 void test_autodiff()
 {
   for(int i = 0; i < g_repeat; i++) {
@@ -226,5 +244,6 @@ void test_autodiff()
   }
 
   bug_1222();
+  bug_1223();
 }