[gjs] function: Use proper type flags on return ffi return value

[Philip Chimento <pchimento src gnome org>]

commit 63f2307120aa94d6ce0a177ec740494165623f00
Author: Marco Trevisan (Treviño) <mail 3v1n0 net>
Date:   Mon Oct 26 21:32:41 2020 +0100

    function: Use proper type flags on return ffi return value
    
    As we're now handling both functions internally, we can just follow the
    rest of the code and set ffi return values using gjs_arg_menber
    functions

 gi/function.cpp | 15 ++++++++++-----
 1 file changed, 10 insertions(+), 5 deletions(-)
---
diff --git a/gi/function.cpp b/gi/function.cpp
index da060607..8f5a1e5e 100644
--- a/gi/function.cpp
+++ b/gi/function.cpp
@@ -746,19 +746,23 @@ static void* get_return_ffi_pointer_from_giargument(
     if (return_arg->skip_out())
         return nullptr;
 
-    // FIXME: Note that v_long and v_ulong don't have type-safe template
-    // overloads yet, and I don't understand why they won't compile
     switch (g_type_info_get_tag(&return_arg->type_info)) {
         case GI_TYPE_TAG_INT8:
+            return &gjs_arg_member<int8_t>(return_value);
         case GI_TYPE_TAG_INT16:
+            return &gjs_arg_member<int16_t>(return_value);
         case GI_TYPE_TAG_INT32:
-            return &return_value->v_long;
+            return &gjs_arg_member<int32_t>(return_value);
         case GI_TYPE_TAG_UINT8:
+            return &gjs_arg_member<uint8_t>(return_value);
         case GI_TYPE_TAG_UINT16:
+            return &gjs_arg_member<uint16_t>(return_value);
         case GI_TYPE_TAG_UINT32:
+            return &gjs_arg_member<uint32_t>(return_value);
         case GI_TYPE_TAG_BOOLEAN:
+            return &gjs_arg_member<gboolean, GI_TYPE_TAG_BOOLEAN>(return_value);
         case GI_TYPE_TAG_UNICHAR:
-            return &return_value->v_ulong;
+            return &gjs_arg_member<uint32_t>(return_value);
         case GI_TYPE_TAG_INT64:
             return &gjs_arg_member<int64_t>(return_value);
         case GI_TYPE_TAG_UINT64:
@@ -774,7 +778,8 @@ static void* get_return_ffi_pointer_from_giargument(
             switch (g_base_info_get_type(info)) {
                 case GI_INFO_TYPE_ENUM:
                 case GI_INFO_TYPE_FLAGS:
-                    return &return_value->v_long;
+                    return &gjs_arg_member<int, GI_TYPE_TAG_INTERFACE>(
+                        return_value);
                 default:
                     return &gjs_arg_member<void*>(return_value);
             }