Added support for type alias

Examples/test-suite/cpp11_type_aliasing.i

@@ -2,15 +2,6 @@
 
 // Type aliasing seg fault : Github issue #424
 
-%warnfilter(SWIGWARN_CPP11_ALIAS_DECLARATION) Target;
-%warnfilter(SWIGWARN_CPP11_ALIAS_DECLARATION) Int;
-%warnfilter(SWIGWARN_CPP11_ALIAS_DECLARATION) IntRef;
-%warnfilter(SWIGWARN_CPP11_ALIAS_DECLARATION) IntPtrRef;
-%warnfilter(SWIGWARN_CPP11_ALIAS_DECLARATION) IntRValueRef;
-%warnfilter(SWIGWARN_CPP11_ALIAS_DECLARATION) IntArray;
-%warnfilter(SWIGWARN_CPP11_ALIAS_DECLARATION) HalideTargetPtr1;
-%warnfilter(SWIGWARN_CPP11_ALIAS_DECLARATION) HalideTargetPtr2;
-
 %inline %{
 namespace Halide {
 
@@ -53,14 +44,69 @@ public:
 
 
 %inline %{
-using Int = int;
-using IntRef = int&;
-using IntPtrRef = int*&;
-using IntRValueRef = int&&;
-using IntArray = int[];
-
 using HalideTargetPtr1 = Halide::Target*;
 namespace Halide {
   using HalideTargetPtr2 = Target*;
 }
 %}
+
+// Define some types
+
+%inline %{
+using Int = int;
+using IntPtr = Int*;
+using IntRef = Int&;
+using IntPtrRef = Int*&;
+using IntRValueRef = Int&&;
+using IntArray = Int[];
+%}
+
+// Test that SWIG understands these new types
+
+%callback("%s_cb");
+Int mult2(Int x);
+%nocallback;
+
+%inline %{
+Int mult2(Int x) { return x * 2; }
+IntPtr allocate_int() { return new Int(12); }
+void free_int(int* ptr) { delete ptr; }
+void inplace_mult2(IntRef x) { x *= 2; }
+Int read_int(IntPtr ptr) { return *ptr; }
+
+template <typename T> class Pair {
+public:
+  using data_t = T;
+
+  data_t a, b;
+
+  Pair() : a(), b() { }
+  Pair(data_t a, data_t b) : a(a), b(b) { }
+  data_t first() { return a; }
+  data_t second() { return b; }
+};
+%}
+
+%template(int_pair) Pair<Int>;
+
+%inline %{
+using PairInt = Pair<Int>;
+
+class PairSubclass : public PairInt {
+public:
+  PairSubclass(data_t a, data_t b) : PairInt(a, b) { }
+
+  using const_ref_data_t = const data_t&;
+};
+
+PairSubclass::data_t plus1(PairSubclass::const_ref_data_t x) { return x + 1; }
+%}
+
+// Test function pointers
+
+%inline %{
+using callback_t = int(*)(int);
+
+callback_t get_callback() { return mult2; }
+int call(callback_t func, int param) { return func(param); }
+%}

Examples/test-suite/errors/cpp_using_type_aliasing.stderr

@@ -1,3 +0,0 @@
-cpp_using_type_aliasing.i:8: Warning 341: The 'using' keyword in type aliasing is not fully supported yet.
-cpp_using_type_aliasing.i:8: Warning 315: Nothing known about 'Okay< int >'.
-cpp_using_type_aliasing.i:8: Warning 315: Nothing known about 'Okay< int >'.

Examples/test-suite/python/cpp11_type_aliasing_runme.py

@@ -0,0 +1,32 @@
+from cpp11_type_aliasing import *
+
+if get_host_target().bits != 32:
+    raise RuntimeError("get_host_target().bits should return 32")
+
+if mult2(10) != 20:
+    raise RuntimeError("mult2(10) should return 20")
+
+int_ptr = allocate_int()
+inplace_mult2(int_ptr)
+if read_int(int_ptr) != 24:
+    raise RuntimeError("read_int should return 24")
+free_int(int_ptr)
+
+pair = PairSubclass(3, 4)
+if pair.first() != 3:
+    raise RuntimeError("pair.first() should return 3")
+
+if pair.second() != 4:
+    raise RuntimeError("pair.second() should return 4")
+
+if pair.a != 3:
+    raise RuntimeError("pair.a should be 3")
+
+if plus1(5) != 6:
+    raise RuntimeError("plus1(5) should return 6")
+
+if call(mult2_cb, 7) != 14:
+    raise RuntimeError("call(mult2_cb, 7) should return 14")
+
+if call(get_callback(), 7) != 14:
+    raise RuntimeError("call(get_callback(), 7) should return 14")