Add function recursion testing to the link-time validation.

git-svn-id: https://cvs.khronos.org/svn/repos/ogl/trunk/ecosystem/public/sdk/tools/glslang@23309 e7fa87d3-cd2b-0410-9028-fcbf551c1848

Test/recurse1.vert

@@ -0,0 +1,44 @@
+#version 330 core
+
+void main() {}
+
+float bar(int);
+
+// direct recursion
+
+void self()
+{
+    self();
+}
+
+// two-level recursion
+
+void foo(float)
+{
+	bar(2);
+}
+
+float bar(int)
+{
+	foo(4.2);
+
+	return 3.2;
+}
+
+// four-level, out of order
+
+void B();
+void D();
+void A() { B(); }
+void C() { D(); }
+void B() { C(); }
+void D() { A(); }
+
+// high degree
+
+void BT();
+void DT();
+void AT() { BT(); BT(); BT(); }
+void CT() { DT(); AT(); DT(); BT(); }
+void BT() { CT(); CT(); CT(); }
+void DT() { AT(); }