From 6fe0f983607e868ed3847e781727c9912429f73e Mon Sep 17 00:00:00 2001 From: Emmanuele Bassi Date: Tue, 14 Sep 2021 16:09:22 +0100 Subject: [PATCH] Add a (diagnostic) warning for finalized floating objects MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit GTK currently checks if a GtkWidget is finalized while still using a floating reference—i.e. a widget was disposed without any parent container owning it. This warning can be useful to identify and trace ownership transfer issues in libraries using initially unowned floating object types. To avoid introducing constraints ex post, we can gate this check behind both the G_ENABLE_DEBUG compile time flag for GLib, and behind the G_ENABLE_DIAGNOSTIC environment variable run time check. Fixes: #2489 --- gobject/gobject.c | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) diff --git a/gobject/gobject.c b/gobject/gobject.c index 9776d7c95..2d950a687 100644 --- a/gobject/gobject.c +++ b/gobject/gobject.c @@ -1180,6 +1180,24 @@ g_object_real_dispose (GObject *object) g_datalist_id_set_data (&object->qdata, quark_weak_refs, NULL); } +static gboolean +floating_check (GObject *object) +{ + static const char *g_enable_diagnostic = NULL; + + if (G_UNLIKELY (g_enable_diagnostic == NULL)) + { + g_enable_diagnostic = g_getenv ("G_ENABLE_DIAGNOSTIC"); + if (g_enable_diagnostic == NULL) + g_enable_diagnostic = "0"; + } + + if (g_enable_diagnostic[0] == '1') + return g_object_is_floating (object); + + return FALSE; +} + static void g_object_finalize (GObject *object) { @@ -1189,6 +1207,17 @@ g_object_finalize (GObject *object) G_OBJECT_TYPE_NAME (object), object); } +#ifdef G_ENABLE_DEBUG + if (floating_check (object)) + { + g_critical ("A floating object %s %p was finalized. This means that someone\n" + "called g_object_unref() on an object that had only a floating\n" + "reference; the initial floating reference is not owned by anyone\n" + "and must be removed with g_object_ref_sink().", + G_OBJECT_TYPE_NAME (object), object); + } +#endif + g_datalist_clear (&object->qdata); GOBJECT_IF_DEBUG (OBJECTS,