Add cling version of test for ROOT-7037

test/Autoloading/AutoForwarding.C

@@ -9,6 +9,23 @@
 // RUN: cat %s | %cling -I%S -Xclang -verify
 // Test FwdPrinterTest
 
+// Test similar to ROOT-7037
+// Equivalent to parsing the dictionary preamble
+.T Def2b.h fwd_Def2b.h
+#include "fwd_Def2b.h"
+// Then doing the autoparsing
+#include "Def2b.h"
+A<int> ai2;
+// And then do both a second time with a different template instantiation.
+.T Def2c.h fwd_Def2c.h
+#include "fwd_Def2c.h"
+#include "Def2c.h"
+
+// In some implementations the AutoloadingVisitor was stripping the default
+// template parameter value from the class template definition leading to
+// compilation error at this next line:
+A<float> af2;
+
 .T Def2.h fwd_Def2.h
 #include "fwd_Def2.h"
 #include "Def2.h"

test/Autoloading/Def2a.h

@@ -0,0 +1,5 @@
+#ifndef DEF2_A
+#define DEF2_A
+template<class T, class U=int>
+class A{};
+#endif

test/Autoloading/Def2b.h

@@ -0,0 +1,2 @@
+#include "Def2a.h"
+A<int> bc;

test/Autoloading/Def2c.h

@@ -0,0 +1,12 @@
+// In the ROOT case, the duplicated default parameter definition is suppressed
+// when it is due to two annotated forward decl (i.e. the $clingAutoload$ ones)
+// Since in standalone cling this is not the case, let's 'emulate' that behavior
+// by remove the default from the declaration.
+
+//#include "Def2a.h"
+#ifndef DEF2_A
+template<class T, class U>
+class A{};
+#endif
+
+A<float,int> ac;