[C++ PATCH] Add test for c++/77747

[Marek Polacek]

This was fixed by r241765 but we didn't have an explicit test that tests if we
detect the error of inheriting constructors from an indirect base.

Tested on x86_64-linux, applying to trunk.

2019-06-07  Marek Polacek  <pola...@redhat.com>

        PR c++/77747
        * g++.dg/cpp0x/inh-ctor33.C: New test.

diff --git gcc/testsuite/g++.dg/cpp0x/inh-ctor33.C 
gcc/testsuite/g++.dg/cpp0x/inh-ctor33.C
new file mode 100644
index 00000000000..95b7812f054
--- /dev/null
+++ gcc/testsuite/g++.dg/cpp0x/inh-ctor33.C
@@ -0,0 +1,19 @@
+// PR c++/77747
+// { dg-do compile { target c++11 } }
+
+class X {
+public:
+  X() { }
+  X(int a) { }
+};
+
+class Y : public X { };
+
+class Z : public Y {
+  using X::X; // { dg-error "cannot inherit constructors from indirect base 
.X." }
+};
+
+int main()
+{
+  Z z{3}; // { dg-error "no matching" }
+}