Raises of Internal_FLTK_Error now come with error messages

1 files changed, 9 insertions, 5 deletions

diff --git a/body/fltk-widgets-valuators-dials.adb b/body/fltk-widgets-valuators-dials.adb
index 6dc9e69..93a636a 100644
--- a/body/fltk-widgets-valuators-dials.adb
+++ b/body/fltk-widgets-valuators-dials.adb
@@ -270,17 +270,21 @@ package body FLTK.Widgets.Valuators.Dials is
            (This       : in out Dial;
             Event      : in     Event_Kind;
             X, Y, W, H : in     Integer)
-        return Event_Outcome is
-    begin
-        return Event_Outcome'Val (fl_dial_handle2
+        return Event_Outcome
+    is
+        Result : Interfaces.C.int := fl_dial_handle2
            (This.Void_Ptr,
             Event_Kind'Pos (Event),
             Interfaces.C.int (X),
             Interfaces.C.int (Y),
             Interfaces.C.int (W),
-            Interfaces.C.int (H)));
+            Interfaces.C.int (H));
+    begin
+        return Event_Outcome'Val (Result);
     exception
-    when Constraint_Error => raise Internal_FLTK_Error;
+    when Constraint_Error => raise Internal_FLTK_Error with
+        "Fl_Dial::handle returned unexpected int value of " &
+        Interfaces.C.int'Image (Result);
     end Handle;