1 files changed, 10 insertions, 0 deletions

diff --git a/src/pgtkterm.c b/src/pgtkterm.c
index d62e2a3b16d..224c01551b7 100644
--- a/src/pgtkterm.c
+++ b/src/pgtkterm.c
@@ -5464,6 +5464,12 @@ pgtk_emacs_to_gtk_modifiers (struct pgtk_display_info *dpyinfo, int state)
 #define IsMiscFunctionKey(keysym) (0xff60 <= (keysym) && (keysym) < 0xff6c)
 #define IsKeypadKey(keysym)       (0xff80 <= (keysym) && (keysym) < 0xffbe)
 #define IsFunctionKey(keysym)     (0xffbe <= (keysym) && (keysym) < 0xffe1)
+#define IsModifierKey(keysym)                                                   \
+  ((((keysym) >= GDK_KEY_Shift_L) && ((keysym) <= GDK_KEY_Hyper_R))             \
+   || (((keysym) >= GDK_KEY_ISO_Lock) && ((keysym) <= GDK_KEY_ISO_Level5_Lock)) \
+   || ((keysym) == GDK_KEY_Mode_switch)                                         \
+   || ((keysym) == GDK_KEY_Num_Lock))
+
 
 void
 pgtk_enqueue_string (struct frame *f, gchar * str)
@@ -5680,6 +5686,10 @@ key_press_event (GtkWidget * widget, GdkEvent * event, gpointer * user_data)
            || (orig_keysym & (1 << 28))
            || (keysym != GDK_KEY_VoidSymbol && nbytes == 0))
           && !(event->key.is_modifier
+               /* Gtk's modifier keys are different from Xlib's ones.
+                * I need to exclude them.
+                */
+               || IsModifierKey (orig_keysym)
                /* The symbols from GDK_KEY_ISO_Lock
                   to GDK_KEY_ISO_Last_Group_Lock
                   don't have real modifiers but