diff --git a/configure.ac b/configure.ac
index d50c91ec3f..796925af1f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -619,7 +619,7 @@ dnl - src and build dirs need to be added because every piece that gets built
 dnl   will need the GStreamer source and generated headers
 dnl LIBS: XML doesn't need to be added because we don't explicitly use symbols
 dnl       from LibXML except for in the core library
-GST_ALL_CFLAGS="-I\$(top_srcdir)/libs -I\$(top_srcdir) -I\$(top_builddir)/libs -I\$(top_builddir) $GLIB_CFLAGS $XML_CFLAGS \$(GST_OPTION_CFLAGS)"
+GST_ALL_CFLAGS="-I\$(top_srcdir)/libs -I\$(top_srcdir) -I\$(top_builddir)/libs -I\$(top_builddir) $GLIB_CFLAGS $XML_CFLAGS \$(GST_OPTION_CFLAGS) -DG_THREADS_MANDATORY"
 
 dnl FIXME: check if LTLIBINTL is needed everywhere
 dnl I presume it is given that it contains the symbols that _() stuff maps to
diff --git a/gst/gst.c b/gst/gst.c
index a59ea5af18..dff1c80cc2 100644
--- a/gst/gst.c
+++ b/gst/gst.c
@@ -364,7 +364,11 @@ gst_init_get_option_group (void)
    * called gst_init() yet or initialised the threading system otherwise, we
    * better issue a warning here (since chances are high that the application
    * has already called other GLib functions such as g_option_context_new() */
+#if GLIB_CHECK_VERSION (2,20,0)
+  if (!g_thread_get_initialized ()) {
+#else
   if (!g_thread_supported ()) {
+#endif
     g_warning ("The GStreamer function gst_init_get_option_group() was\n"
         "\tcalled, but the GLib threading system has not been initialised\n"
         "\tyet, something that must happen before any other GLib function\n"
@@ -417,7 +421,11 @@ gst_init_check (int *argc, char **argv[], GError ** err)
 #endif
   gboolean res;
 
+#if GLIB_CHECK_VERSION (2,20,0)
+  if (!g_thread_get_initialized ())
+#else
   if (!g_thread_supported ())
+#endif
     g_thread_init (NULL);
 
   if (gst_initialized) {
@@ -514,8 +522,8 @@ prepare_for_load_plugin_func (gpointer data, gpointer user_data)
 
 #ifndef GST_DISABLE_OPTION_PARSING
 static void
-split_and_iterate (const gchar * stringlist, gchar * separator, GFunc iterator,
-    gpointer user_data)
+split_and_iterate (const gchar * stringlist, gchar * separator,
+    GFunc iterator, gpointer user_data)
 {
   gchar **strings;
   gint j = 0;
@@ -562,7 +570,11 @@ init_pre (GOptionContext * context, GOptionGroup * group, gpointer data,
   g_type_init ();
 
   /* we need threading to be enabled right here */
+#if GLIB_CHECK_VERSION (2,20,0)
+  g_assert (g_thread_get_initialized ());
+#else
   g_assert (g_thread_supported ());
+#endif
   _gst_debug_init ();
 
 #ifdef ENABLE_NLS
diff --git a/pkgconfig/gstreamer-uninstalled.pc.in b/pkgconfig/gstreamer-uninstalled.pc.in
index fa518cd033..674b30db55 100644
--- a/pkgconfig/gstreamer-uninstalled.pc.in
+++ b/pkgconfig/gstreamer-uninstalled.pc.in
@@ -11,4 +11,4 @@ Description: Streaming media framework, Not Installed
 Version: @VERSION@
 Requires: @GST_PKG_DEPS@@LIBXML_PKG@
 Libs: ${libdir}/gst/libgstreamer-@GST_MAJORMINOR@.la
-Cflags: -I${includedir}  -I@srcdir@/.. -I${includedir}/libs  -I@srcdir@/../libs
+Cflags: -I${includedir}  -I@srcdir@/.. -I${includedir}/libs  -I@srcdir@/../libs -DG_THREADS_MANDATORY
diff --git a/pkgconfig/gstreamer.pc.in b/pkgconfig/gstreamer.pc.in
index 32fd81182d..3cbe181f6b 100644
--- a/pkgconfig/gstreamer.pc.in
+++ b/pkgconfig/gstreamer.pc.in
@@ -10,4 +10,4 @@ Description: Streaming media framework
 Requires: @GST_PKG_DEPS@@LIBXML_PKG@
 Version: @VERSION@
 Libs: -L${libdir} -lgstreamer-@GST_MAJORMINOR@
-Cflags: -I${includedir}
+Cflags: -I${includedir} -DG_THREADS_MANDATORY