diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index f576273d9c1b..98f8733110b3 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2017-03-09  Paolo Carlini  <paolo.carlini@oracle.com>
+
+	PR c++/71966
+	* g++.dg/cpp0x/pr71966-1.C: New.
+	* g++.dg/cpp0x/pr71966-2.C: Likewise.
+
 2017-03-09  Martin Liska  <mliska@suse.cz>
 
 	PR tree-optimization/79631
diff --git a/gcc/testsuite/g++.dg/cpp0x/pr71966-1.C b/gcc/testsuite/g++.dg/cpp0x/pr71966-1.C
new file mode 100644
index 000000000000..76327201382f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/pr71966-1.C
@@ -0,0 +1,13 @@
+// PR c++/71966
+// { dg-do compile { target c++11 } }
+
+struct A
+{ 
+  constexpr A (int);  // { dg-message "never defined" }
+  constexpr operator int () const { return 0; }
+};
+
+template < int > struct B {};
+
+constexpr A a = 0;  // { dg-error "before its definition" }
+B < a > b;
diff --git a/gcc/testsuite/g++.dg/cpp0x/pr71966-2.C b/gcc/testsuite/g++.dg/cpp0x/pr71966-2.C
new file mode 100644
index 000000000000..aedd4cea7f3b
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/pr71966-2.C
@@ -0,0 +1,15 @@
+// PR c++/71966
+// { dg-do compile { target c++11 } }
+
+struct A
+{ 
+  constexpr A (int);  // { dg-message "never defined" }
+  constexpr operator int () const { return 0; }
+  int c;
+};
+
+template <int>
+struct B {};
+
+constexpr A a = 0;  // { dg-error "before its definition" }
+B<a> b;