diff --git a/cfg/gtk.cfg b/cfg/gtk.cfg
index 024f567c922..2c02c567f30 100644
--- a/cfg/gtk.cfg
+++ b/cfg/gtk.cfg
@@ -717,6 +717,12 @@
     <alloc init="true" no-fail="true">g_variant_type_dup_string</alloc>
     <alloc init="true" no-fail="true">g_value_dup_string</alloc>
     <use>g_register_data</use>
+    <use>g_idle_add</use>
+    <use>g_idle_add_full</use>
+    <use>g_timeout_add</use>
+    <use>g_timeout_add_full</use>
+    <use>g_timeout_add_seconds</use>
+    <use>g_timeout_add_seconds_full</use>
     <dealloc>g_free</dealloc>
   </memory>
   <memory>
@@ -4237,7 +4243,6 @@
   </function>
   <!--guint g_idle_add (GSourceFunc function, gpointer data); -->
   <function name="g_idle_add">
-    <leak-ignore/>
     <noreturn>false</noreturn>
     <returnValue type="guint"/>
     <arg nr="1" direction="in">
@@ -4249,7 +4254,6 @@
   </function>
   <!--guint g_idle_add_full (gint priority, GSourceFunc function, gpointer data, GDestroyNotify notify); -->
   <function name="g_idle_add_full">
-    <leak-ignore/>
     <noreturn>false</noreturn>
     <returnValue type="guint"/>
     <arg nr="1">
@@ -5652,7 +5656,6 @@
   <!-- guint g_timeout_add ( guint interval, GSourceFunc function, gpointer data) -->
   <!-- guint g_timeout_add_seconds ( guint interval, GSourceFunc function, gpointer data) -->
   <function name="g_timeout_add,g_timeout_add_seconds">
-    <leak-ignore/>
     <noreturn>false</noreturn>
     <returnValue type="guint"/>
     <arg nr="1" direction="in">
@@ -5669,7 +5672,6 @@
   </function>
   <!-- guint g_timeout_add_full (gint priority, guint interval, GSourceFunc function, gpointer data, GDestroyNotify notify) -->
   <function name="g_timeout_add_full,g_timeout_add_seconds_full">
-    <leak-ignore/>
     <noreturn>false</noreturn>
     <returnValue type="guint"/>
     <arg nr="1" direction="in">
diff --git a/test/cfg/gtk.c b/test/cfg/gtk.c
index 2612b572638..1a19e6c9929 100644
--- a/test/cfg/gtk.c
+++ b/test/cfg/gtk.c
@@ -730,3 +730,45 @@ int g_define_enum_and_flags_type_test(void) {
     return e + f;
 }
 #endif
+
+static gboolean source_func_frees_data(gpointer data)
+{
+    g_free(data);
+    return FALSE;
+}
+
+static void destroy_notify_frees_data(gpointer data)
+{
+    g_free(data);
+}
+
+// The data passed to a GSource is owned by the callback or the destroy notify
+// from then on, so it does not leak.
+void g_idle_add_takes_data_test(void)
+{
+    // cppcheck-suppress constVariablePointer
+    gchar *data = g_strdup("data");
+    g_idle_add(source_func_frees_data, data);
+
+    gchar *data_full = g_strdup("data");
+    g_idle_add_full(200, source_func_frees_data, data_full, NULL);
+}
+
+void g_timeout_add_takes_data_test(void)
+{
+    // cppcheck-suppress constVariablePointer
+    gchar *data = g_strdup("data");
+    g_timeout_add(10, source_func_frees_data, data);
+
+    // cppcheck-suppress constVariablePointer
+    gchar *data_seconds = g_strdup("data");
+    g_timeout_add_seconds(1, source_func_frees_data, data_seconds);
+
+    // cppcheck-suppress constVariablePointer
+    gchar *data_full = g_strdup("data");
+    g_timeout_add_full(0, 10, source_func_frees_data, data_full, destroy_notify_frees_data);
+
+    // cppcheck-suppress constVariablePointer
+    gchar *data_seconds_full = g_strdup("data");
+    g_timeout_add_seconds_full(0, 1, source_func_frees_data, data_seconds_full, destroy_notify_frees_data);
+}