change return value of Type::pointee_type() to Option<Type>

Author: Rohan Prinja

src/clang.rs

@@ -647,11 +647,19 @@ impl Type {
 
     /// Given that this type is a pointer type, return the type that it points
     /// to.
-    pub fn pointee_type(&self) -> Type {
-        unsafe {
-            Type {
-                x: clang_getPointeeType(self.x),
+    pub fn pointee_type(&self) -> Option<Type> {
+        match self.kind() {
+            CXType_Pointer |
+            CXType_RValueReference |
+            CXType_LValueReference |
+            CXType_MemberPointer => {
+                let ret = Type {
+                    x: unsafe { clang_getPointeeType(self.x) },
+                };
+                debug_assert!(ret.kind() != CXType_Invalid);
+                Some(ret)
             }
+            _ => None,
         }
     }
 

src/ir/ty.rs

@@ -677,21 +677,19 @@ impl Type {
             // process of resolving them.
             CXType_MemberPointer |
             CXType_Pointer => {
-                let inner = Item::from_ty_or_ref(ty.pointee_type(),
-                                                 location,
-                                                 parent_id,
-                                                 ctx);
+                let inner =
+                    Item::from_ty_or_ref(ty.pointee_type().unwrap(), location,
+                                         parent_id, ctx);
                 TypeKind::Pointer(inner)
             }
             CXType_BlockPointer => TypeKind::BlockPointer,
             // XXX: RValueReference is most likely wrong, but I don't think we
             // can even add bindings for that, so huh.
             CXType_RValueReference |
             CXType_LValueReference => {
-                let inner = Item::from_ty_or_ref(ty.pointee_type(),
-                                                 location,
-                                                 parent_id,
-                                                 ctx);
+                let inner =
+                    Item::from_ty_or_ref(ty.pointee_type().unwrap(), location,
+                                         parent_id, ctx);
                 TypeKind::Reference(inner)
             }
             // XXX DependentSizedArray is wrong