[gjs: 7/12] value: Rewrite incorrect and obsolete comments

[Philip Chimento <pchimento src gnome org>]

commit 39d54989e6c2f26eba964ba13fbf02dff1ea37db
Author: Philip Chimento <philip chimento gmail com>
Date:   Sun Mar 21 19:59:11 2021 -0700

    value: Rewrite incorrect and obsolete comments
    
    FIXME: Check what happens if GValue remains uninitialized

 gi/value.cpp | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)
---
diff --git a/gi/value.cpp b/gi/value.cpp
index fea7f9da..bba2702a 100644
--- a/gi/value.cpp
+++ b/gi/value.cpp
@@ -267,11 +267,14 @@ closure_marshal(GClosure        *closure,
             exit(code);
     }
 
-    // Any exception now pending, is handled when returning control to JS
-
+    // null return_value means the closure wasn't expected to return a value.
+    // Discard the JS function's return value in that case.
     if (return_value != NULL) {
         if (rval.isUndefined()) {
-            /* something went wrong invoking, error should be set already */
+            // Either an exception was thrown and logged, or the JS function
+            // returned undefined. Leave the GValue uninitialized.
+            // FIXME: not sure what happens on the other side with an
+            // uninitialized GValue!
             return;
         }