From 5a71eb598585f0413ed630f5007f3c0295c7ba60 Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Wed, 18 May 2016 14:03:03 +0200
Subject: [PATCH] Big 1213: add regression unit test.

---
 test/CMakeLists.txt   |  2 ++
 test/bug1213.cpp      | 13 +++++++++++++
 test/bug1213.h        |  8 ++++++++
 test/bug1213_main.cpp | 18 ++++++++++++++++++
 4 files changed, 41 insertions(+)
 create mode 100644 test/bug1213.cpp
 create mode 100644 test/bug1213.h
 create mode 100644 test/bug1213_main.cpp

diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 3c0f9b685..9d49f1e97 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -259,6 +259,8 @@ ei_add_test(dense_storage)
 ei_add_test(ctorleak)
 ei_add_test(mpl2only)
 
+add_executable(bug1213 bug1213.cpp bug1213_main.cpp)
+
 check_cxx_compiler_flag("-ffast-math" COMPILER_SUPPORT_FASTMATH)
 if(COMPILER_SUPPORT_FASTMATH)
   set(EIGEN_FASTMATH_FLAGS "-ffast-math")
diff --git a/test/bug1213.cpp b/test/bug1213.cpp
new file mode 100644
index 000000000..581760c1a
--- /dev/null
+++ b/test/bug1213.cpp
@@ -0,0 +1,13 @@
+
+// This anonymous enum is essential to trigger the linking issue
+enum {
+  Foo
+};
+
+#include "bug1213.h"
+
+bool bug1213_1(const Eigen::Vector3f& x)
+{
+  return bug1213_2(x);
+}
+
diff --git a/test/bug1213.h b/test/bug1213.h
new file mode 100644
index 000000000..040e5a470
--- /dev/null
+++ b/test/bug1213.h
@@ -0,0 +1,8 @@
+
+#include <Eigen/Core>
+
+template<typename T, int dim>
+bool bug1213_2(const Eigen::Matrix<T,dim,1>& x);
+
+bool bug1213_1(const Eigen::Vector3f& x);
+
diff --git a/test/bug1213_main.cpp b/test/bug1213_main.cpp
new file mode 100644
index 000000000..4802c0003
--- /dev/null
+++ b/test/bug1213_main.cpp
@@ -0,0 +1,18 @@
+
+// This is a regression unit regarding a weird linking issue with gcc.
+
+#include "bug1213.h"
+
+int main()
+{
+  return 0;
+}
+
+
+template<typename T, int dim>
+bool bug1213_2(const Eigen::Matrix<T,dim,1>& )
+{
+  return true;
+}
+
+template bool bug1213_2<float,3>(const Eigen::Vector3f&);