re PR c++/87125 (ICE in tsubst_copy starting with r261084)

	PR c++/87125
	* g++.dg/cpp0x/pr87125.C: New test.

From-SVN: r267324

gcc/testsuite/ChangeLog

+2018-12-21  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/87125
+	* g++.dg/cpp0x/pr87125.C: New test.
+
 2018-12-21  Thomas Preud'homme  <thomas.preudhomme@linaro.org>
 
 	* gcc.target/arm/size-optimization-ieee-1.c: Skip if passing

gcc/testsuite/g++.dg/cpp0x/pr87125.C

+// PR c++/87125
+// { dg-do compile { target c++11 } }
+
+template <typename T>
+struct S {
+  template <typename U>
+  constexpr S (U) noexcept (T ()) {}
+};
+struct V : S<int> { using S::S; };
+
+bool
+foo ()
+{
+  return noexcept (V (0));
+}