diff --git a/ChangeLog b/ChangeLog
index 67bce88a..2689e59d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -4,6 +4,8 @@
 - openslide2vips gets underlying tile size from openslide
 - embed has 'background' option
 - dzsave --layout google has a @background option
+- use vips_mutex_new()/_free() over g_mutex_new()/_free()
+- remove no threads option
 
 2/10/12 started 7.30.4
 - remove options from format string in .dzi (thanks Martin)
diff --git a/configure.in b/configure.in
index 4e631242..184df20a 100644
--- a/configure.in
+++ b/configure.in
@@ -318,16 +318,10 @@ AC_CHECK_LIB(m,hypot,[AC_DEFINE(HAVE_HYPOT,1,[have hypot() in libm.])])
 PKG_CHECK_MODULES(REQUIRED, glib-2.0 >= 2.6 gmodule-2.0 >= 2.4 libxml-2.0 gobject-2.0)
 PACKAGES_USED="$PACKAGES_USED glib-2.0 gmodule-2.0 libxml-2.0 gobject-2.0"
 
-# option to eval without threads
-AC_ARG_ENABLE(threads, 
-  AS_HELP_STRING([--enable-threads], [evaluate with threads (default: yes)]))
-
-if test x"$enable_threads" != "xno"; then
-  AC_DEFINE(HAVE_THREADS,1,[threaded evaluation])
-  PKG_CHECK_MODULES(GTHREAD, gthread-2.0)
-  PACKAGES_USED="$PACKAGES_USED gthread-2.0"
-  enable_threads=yes
-fi
+# after 2.32 g_mutex_new() becomes g_mutex_init(), annoyingly
+PKG_CHECK_MODULES(THREADS, glib-2.0 >= 2.32,[
+  AC_DEFINE(HAVE_MUTEX_INIT,1,[define if your glib has g_mutex_init().])
+])
 
 # check for gtk-doc
 GTK_DOC_CHECK(1.9)
@@ -734,7 +728,6 @@ native win32:				$vips_os_win32
 native OS X:				$vips_os_darwin
 open files in binary mode: 		$vips_binary_open
 enable debug:				$enable_debug
-evaluate with threads: 			$enable_threads
 build C++ components:			$enable_cxx
 build docs with gtkdoc:			$enable_gtk_doc
 gobject introspection: 			$found_introspection
diff --git a/libvips/colour/im_icc_transform.c b/libvips/colour/im_icc_transform.c
index 04f765d7..88255b03 100644
--- a/libvips/colour/im_icc_transform.c
+++ b/libvips/colour/im_icc_transform.c
@@ -147,7 +147,7 @@ icc_destroy( Icc *icc )
 	IM_FREEF( cmsDeleteTransform, icc->trans );
 	IM_FREEF( cmsCloseProfile, icc->in_profile );
 	IM_FREEF( cmsCloseProfile, icc->out_profile );
-	IM_FREEF( g_mutex_free, icc->lock );
+	IM_FREEF( vips_mutex_free, icc->lock );
 
 	return( 0 );
 }
@@ -173,7 +173,7 @@ icc_new( IMAGE *in, IMAGE *out, VipsIntent intent )
 	icc->in_profile = 0;
 	icc->out_profile = 0;
 	icc->trans = 0;
-	icc->lock = g_mutex_new();
+	icc->lock = vips_mutex_new();
 
 	if( im_add_close_callback( out, 
 		(im_callback_fn) icc_destroy, icc, NULL ) )
@@ -945,7 +945,7 @@ icc_destroy( Icc *icc )
 	IM_FREEF( cmsDeleteTransform, icc->trans );
 	IM_FREEF( cmsCloseProfile, icc->in_profile );
 	IM_FREEF( cmsCloseProfile, icc->out_profile );
-	IM_FREEF( g_mutex_free, icc->lock );
+	IM_FREEF( vips_mutex_free, icc->lock );
 
 	return( 0 );
 }
@@ -970,7 +970,7 @@ icc_new( IMAGE *in, IMAGE *out, VipsIntent intent )
 	icc->in_profile = 0;
 	icc->out_profile = 0;
 	icc->trans = 0;
-	icc->lock = g_mutex_new();
+	icc->lock = vips_mutex_new();
 
 	if( im_add_close_callback( out, 
 		(im_callback_fn) icc_destroy, icc, NULL ) )
diff --git a/libvips/conversion/sequential.c b/libvips/conversion/sequential.c
index 8a8efc65..e99afb65 100644
--- a/libvips/conversion/sequential.c
+++ b/libvips/conversion/sequential.c
@@ -100,7 +100,7 @@ vips_sequential_dispose( GObject *gobject )
 {
 	VipsSequential *sequential = (VipsSequential *) gobject;
 
-	VIPS_FREEF( g_mutex_free, sequential->lock );
+	VIPS_FREEF( vips_mutex_free, sequential->lock );
 	VIPS_FREEF( g_cond_free, sequential->ready );
 
 	G_OBJECT_CLASS( vips_sequential_parent_class )->dispose( gobject );
@@ -293,7 +293,7 @@ static void
 vips_sequential_init( VipsSequential *sequential )
 {
 	sequential->trace = FALSE;
-	sequential->lock = g_mutex_new();
+	sequential->lock = vips_mutex_new();
 	sequential->ready = g_cond_new();
 	sequential->tile_height = 1;
 	sequential->error = 0;
diff --git a/libvips/conversion/tilecache.c b/libvips/conversion/tilecache.c
index 58d1c143..de2128c7 100644
--- a/libvips/conversion/tilecache.c
+++ b/libvips/conversion/tilecache.c
@@ -144,7 +144,7 @@ vips_block_cache_dispose( GObject *gobject )
 	VipsBlockCache *cache = (VipsBlockCache *) gobject;
 
 	vips_block_cache_drop_all( cache );
-	VIPS_FREEF( g_mutex_free, cache->lock );
+	VIPS_FREEF( vips_mutex_free, cache->lock );
 	VIPS_FREEF( g_cond_free, cache->new_tile );
 
 	G_OBJECT_CLASS( vips_block_cache_parent_class )->dispose( gobject );
@@ -489,7 +489,7 @@ vips_block_cache_init( VipsBlockCache *cache )
 
 	cache->time = 0;
 	cache->ntiles = 0;
-	cache->lock = g_mutex_new();
+	cache->lock = vips_mutex_new();
 	cache->new_tile = g_cond_new();
 	cache->tiles = g_hash_table_new_full( 
 		(GHashFunc) vips_rect_hash, 
diff --git a/libvips/deprecated/im_tile_cache.c b/libvips/deprecated/im_tile_cache.c
index 1fdc7b89..1c348835 100644
--- a/libvips/deprecated/im_tile_cache.c
+++ b/libvips/deprecated/im_tile_cache.c
@@ -105,7 +105,7 @@ tile_destroy( Tile *tile )
 static void
 read_destroy( Read *read )
 {
-	IM_FREEF( g_mutex_free, read->lock );
+	IM_FREEF( vips_mutex_free, read->lock );
 
 	while( read->cache ) {
 		Tile *tile = (Tile *) read->cache->data;
@@ -131,7 +131,7 @@ read_new( IMAGE *in, IMAGE *out,
 	read->max_tiles = max_tiles;
 	read->time = 0;
 	read->ntiles = 0;
-	read->lock = g_mutex_new();
+	read->lock = vips_mutex_new();
 	read->cache = NULL;
 
 	if( im_add_close_callback( out, 
diff --git a/libvips/foreign/fits.c b/libvips/foreign/fits.c
index 07149673..74829da5 100644
--- a/libvips/foreign/fits.c
+++ b/libvips/foreign/fits.c
@@ -133,7 +133,7 @@ static void
 vips_fits_close( VipsFits *fits )
 {
 	VIPS_FREE( fits->filename );
-	VIPS_FREEF( g_mutex_free, fits->lock );
+	VIPS_FREEF( vips_mutex_free, fits->lock );
 
 	if( fits->fptr ) {
 		int status;
@@ -180,7 +180,7 @@ vips_fits_new_read( const char *filename, VipsImage *out, int band_select )
 		return( NULL );
 	}
 
-	fits->lock = g_mutex_new();
+	fits->lock = vips_mutex_new();
 
 	return( fits );
 }
@@ -578,7 +578,7 @@ vips_fits_new_write( VipsImage *in, const char *filename )
 		return( NULL );
 	}
 
-	fits->lock = g_mutex_new();
+	fits->lock = vips_mutex_new();
 
 	return( fits );
 }
diff --git a/libvips/foreign/magick2vips.c b/libvips/foreign/magick2vips.c
index 44d615b3..860a1590 100644
--- a/libvips/foreign/magick2vips.c
+++ b/libvips/foreign/magick2vips.c
@@ -131,7 +131,7 @@ read_destroy( VipsImage *im, Read *read )
 	VIPS_FREEF( DestroyImageInfo, read->image_info ); 
 	VIPS_FREE( read->frames );
 	DestroyExceptionInfo( &read->exception );
-	VIPS_FREEF( g_mutex_free, read->lock );
+	VIPS_FREEF( vips_mutex_free, read->lock );
 
 	return( 0 );
 }
@@ -161,7 +161,7 @@ read_new( const char *filename, VipsImage *im )
 	read->n_frames = 0;
 	read->frames = NULL;
 	read->frame_height = 0;
-	read->lock = g_mutex_new();
+	read->lock = vips_mutex_new();
 
 	g_signal_connect( im, "close", G_CALLBACK( read_destroy ), read );
 
diff --git a/libvips/foreign/vips2tiff.c b/libvips/foreign/vips2tiff.c
index b673aacb..3caedd10 100644
--- a/libvips/foreign/vips2tiff.c
+++ b/libvips/foreign/vips2tiff.c
@@ -1075,7 +1075,7 @@ write_tif_tilewise( TiffWrite *tw )
 		return( -1 );
 
 	g_assert( !tw->write_lock );
-	tw->write_lock = g_mutex_new();
+	tw->write_lock = vips_mutex_new();
 
 	/* Write pyramid too? Only bother if bigger than tile size.
 	 */
@@ -1179,7 +1179,7 @@ free_tiff_write( TiffWrite *tw )
 
 	VIPS_FREEF( TIFFClose, tw->tif );
 	VIPS_FREEF( vips_free, tw->tbuf );
-	VIPS_FREEF( g_mutex_free, tw->write_lock );
+	VIPS_FREEF( vips_mutex_free, tw->write_lock );
 	VIPS_FREEF( free_pyramid, tw->layer );
 	VIPS_FREEF( vips_free, tw->icc_profile );
 }
diff --git a/libvips/include/vips/thread.h b/libvips/include/vips/thread.h
index 77b32635..3a057370 100644
--- a/libvips/include/vips/thread.h
+++ b/libvips/include/vips/thread.h
@@ -43,40 +43,11 @@ extern "C" {
  */
 #define VIPS__DEFAULT_STACK_SIZE (2 * 1024 * 1024)
 
-#ifndef HAVE_THREADS
-#undef g_thread_supported
-#define g_thread_supported() (0)
-
-#define g_thread_init vips__g_thread_init
-#define g_thread_join vips__g_thread_join
-#define g_thread_self vips__g_thread_self
-#define g_thread_create_full vips__g_thread_create_full
-
-/* We don't need a shadow imlementation of g_thread_create(), even though we
- * use it, because it's just a macro over g_thread_create_full().
+/* We need wrappers over g_mutex_new(), it was replaced by g_mutex_init() in
+ * glib 2.32+
  */
-
-void vips__g_thread_init( GThreadFunctions *vtable );
-gpointer vips__g_thread_join( GThread * );
-gpointer vips__g_thread_self( void );
-GThread *vips__g_thread_create_full( GThreadFunc, 
-	gpointer, gulong, gboolean, gboolean, GThreadPriority, GError ** );
-
-#undef g_mutex_new
-#undef g_mutex_free
-#undef g_mutex_lock
-#undef g_mutex_unlock
-
-#define g_mutex_new vips__g_mutex_new
-#define g_mutex_free vips__g_mutex_free
-#define g_mutex_lock vips__g_mutex_lock
-#define g_mutex_unlock vips__g_mutex_unlock
-
-GMutex *vips__g_mutex_new( void );
-void vips__g_mutex_free( GMutex * );
-void vips__g_mutex_lock( GMutex * );
-void vips__g_mutex_unlock( GMutex * );
-#endif /*!HAVE_THREADS*/
+GMutex *vips_mutex_new( void );
+void vips_mutex_free( GMutex * );
 
 #ifdef __cplusplus
 }
diff --git a/libvips/iofuncs/buffer.c b/libvips/iofuncs/buffer.c
index 1399bc51..189203a2 100644
--- a/libvips/iofuncs/buffer.c
+++ b/libvips/iofuncs/buffer.c
@@ -72,15 +72,8 @@ static GSList *vips__buffers_all = NULL;
 static int buffer_cache_n = 0; 
 #endif /*DEBUG_CREATE*/
 
-#ifdef HAVE_THREADS
 static GPrivate *thread_buffer_cache_key = NULL;
-#else /*!HAVE_THREADS*/
-static VipsBufferCache *thread_buffer_cache = NULL;
-#endif /*HAVE_THREADS*/
 
-/* Only need this if we're threading and need to do a lot of start/stop.
- */
-#ifdef HAVE_THREADS
 static void
 buffer_cache_free( VipsBufferCache *cache )
 {
@@ -95,7 +88,6 @@ buffer_cache_free( VipsBufferCache *cache )
 	VIPS_FREEF( g_hash_table_destroy, cache->hash );
 	VIPS_FREE( cache );
 }
-#endif /*HAVE_THREADS*/
 
 static void
 buffer_cache_list_free( VipsBufferCacheList *cache_list )
@@ -163,16 +155,10 @@ buffer_cache_get( void )
 {
 	VipsBufferCache *cache;
 
-#ifdef HAVE_THREADS
 	if( !(cache = g_private_get( thread_buffer_cache_key )) ) {
 		cache = buffer_cache_new();
 		g_private_set( thread_buffer_cache_key, cache );
 	}
-#else /*!HAVE_THREADS*/
-	if( !thread_buffer_cache )
-		thread_buffer_cache = buffer_cache_new();
-	cache = thread_buffer_cache;
-#endif /*HAVE_THREADS*/
 
 	return( cache );
 }
@@ -474,9 +460,7 @@ vips_buffer_print( VipsBuffer *buffer )
 void
 vips__buffer_init( void )
 {
-#ifdef HAVE_THREADS
 	if( !thread_buffer_cache_key ) 
 		thread_buffer_cache_key = g_private_new( 
 			(GDestroyNotify) buffer_cache_free );
-#endif /*HAVE_THREADS*/
 }
diff --git a/libvips/iofuncs/cache.c b/libvips/iofuncs/cache.c
index 02451609..d6838650 100644
--- a/libvips/iofuncs/cache.c
+++ b/libvips/iofuncs/cache.c
@@ -416,7 +416,7 @@ void
 vips__cache_init( void )
 {
 	if( !vips_cache_table ) {
-		vips_cache_lock = g_mutex_new();
+		vips_cache_lock = vips_mutex_new();
 
 		vips_cache_table = g_hash_table_new( 
 			(GHashFunc) vips_operation_hash, 
diff --git a/libvips/iofuncs/image.c b/libvips/iofuncs/image.c
index 4c7b4d07..8994508b 100644
--- a/libvips/iofuncs/image.c
+++ b/libvips/iofuncs/image.c
@@ -241,7 +241,7 @@ vips_image_finalize( GObject *gobject )
 	 */
 	vips_image_delete( image );
 
-	VIPS_FREEF( g_mutex_free, image->sslock );
+	VIPS_FREEF( vips_mutex_free, image->sslock );
 
 	VIPS_FREE( image->Hist );
 	VIPS_FREEF( vips__gslist_gvalue_free, image->history_list );
@@ -1057,7 +1057,7 @@ vips_image_init( VipsImage *image )
 	image->Yres = 1.0;
 
 	image->fd = -1;			/* since 0 is stdout */
-	image->sslock = g_mutex_new();
+	image->sslock = vips_mutex_new();
 
 	image->sizeof_header = VIPS_SIZEOF_HEADER;
 
diff --git a/libvips/iofuncs/init.c b/libvips/iofuncs/init.c
index 9655a35d..8b129f2e 100644
--- a/libvips/iofuncs/init.c
+++ b/libvips/iofuncs/init.c
@@ -201,7 +201,7 @@ vips_init( const char *argv0 )
 #endif /*G_THREADS_ENABLED*/
 
 	if( !vips__global_lock )
-		vips__global_lock = g_mutex_new();
+		vips__global_lock = vips_mutex_new();
 
 	VIPS_SETSTR( vips__argv0, argv0 );
 
diff --git a/libvips/iofuncs/memory.c b/libvips/iofuncs/memory.c
index 79802b6b..d4fb8ef9 100644
--- a/libvips/iofuncs/memory.c
+++ b/libvips/iofuncs/memory.c
@@ -240,21 +240,13 @@ vips_tracked_free( void *s )
 	g_free( s );
 }
 
-/* g_mutex_new() is a macro.
- */
-static void *
-vips_tracked_mutex_new( void *data )
-{
-	return( g_mutex_new() );
-}
-
 static void
 vips_tracked_init( void )
 {
 	static GOnce vips_tracked_once = G_ONCE_INIT;
 
 	vips_tracked_mutex = g_once( &vips_tracked_once, 
-		vips_tracked_mutex_new, NULL );
+		(GThreadFunc) vips_mutex_new, NULL );
 }
 
 /**
diff --git a/libvips/iofuncs/object.c b/libvips/iofuncs/object.c
index 83a6e2de..9d89a41d 100644
--- a/libvips/iofuncs/object.c
+++ b/libvips/iofuncs/object.c
@@ -1271,7 +1271,7 @@ vips_object_class_init( VipsObjectClass *class )
 	if( !vips__object_all ) {
 		vips__object_all = g_hash_table_new( 
 			g_direct_hash, g_direct_equal );
-		vips__object_all_lock = g_mutex_new();
+		vips__object_all_lock = vips_mutex_new();
 	}
 
 	gobject_class->dispose = vips_object_dispose;
diff --git a/libvips/iofuncs/semaphore.c b/libvips/iofuncs/semaphore.c
index 3b4959b8..5ea8184c 100644
--- a/libvips/iofuncs/semaphore.c
+++ b/libvips/iofuncs/semaphore.c
@@ -58,19 +58,15 @@ vips_semaphore_init( VipsSemaphore *s, int v, char *name )
 {
 	s->v = v;
 	s->name = name;
-#ifdef HAVE_THREADS
-	s->mutex = g_mutex_new();
+	s->mutex = vips_mutex_new();
 	s->cond = g_cond_new();
-#endif /*HAVE_THREADS*/
 }
 
 void
 vips_semaphore_destroy( VipsSemaphore *s )
 {
-#ifdef HAVE_THREADS
-	VIPS_FREEF( g_mutex_free, s->mutex );
+	VIPS_FREEF( vips_mutex_free, s->mutex );
 	VIPS_FREEF( g_cond_free, s->cond );
-#endif /*HAVE_THREADS*/
 }
 
 /* Add n to the semaphore and signal any threads that are blocked waiting 
@@ -81,12 +77,10 @@ vips_semaphore_upn( VipsSemaphore *s, int n )
 {
 	int value_after_op;
 
-#ifdef HAVE_THREADS
 	g_mutex_lock( s->mutex );
-#endif /*HAVE_THREADS*/
 	s->v += n;
 	value_after_op = s->v;
-#ifdef HAVE_THREADS
+
 	/* If we are only incrementing by one, we only need to wake a single
 	 * thread. If we are incrementing by a lot, we must wake all threads.
 	 */
@@ -95,7 +89,6 @@ vips_semaphore_upn( VipsSemaphore *s, int n )
 	else
 		g_cond_broadcast( s->cond );
 	g_mutex_unlock( s->mutex );
-#endif /*HAVE_THREADS*/
 
 #ifdef DEBUG_IO
 	printf( "vips_semaphore_upn(\"%s\",%d) = %d\n", 
@@ -122,16 +115,14 @@ vips_semaphore_downn( VipsSemaphore *s, int n )
 {
 	int value_after_op;
 
-#ifdef HAVE_THREADS
 	g_mutex_lock( s->mutex );
+
 	while( s->v < n )
 		g_cond_wait( s->cond, s->mutex );
-#endif /*HAVE_THREADS*/
 	s->v -= n;
 	value_after_op = s->v;
-#ifdef HAVE_THREADS
+
 	g_mutex_unlock( s->mutex );
-#endif /*HAVE_THREADS*/
 
 #ifdef DEBUG_IO
 	printf( "vips_semaphore_downn(\"%s\",%d): %d\n", 
diff --git a/libvips/iofuncs/sinkdisc.c b/libvips/iofuncs/sinkdisc.c
index d82d824a..621f2618 100644
--- a/libvips/iofuncs/sinkdisc.c
+++ b/libvips/iofuncs/sinkdisc.c
@@ -171,7 +171,6 @@ wbuffer_write( WriteBuffer *wbuffer )
 		&wbuffer->area, write->a );
 }
 
-#ifdef HAVE_THREADS
 /* Run this as a thread to do a BG write.
  */
 static void *
@@ -200,7 +199,6 @@ wbuffer_write_thread( void *data )
 
 	return( NULL );
 }
-#endif /*HAVE_THREADS*/
 
 static WriteBuffer *
 wbuffer_new( Write *write )
@@ -227,7 +225,6 @@ wbuffer_new( Write *write )
 	 */
 	vips__region_no_ownership( wbuffer->region );
 
-#ifdef HAVE_THREADS
 	/* Make this last (picks up parts of wbuffer on startup).
 	 */
 	if( !(wbuffer->thread = g_thread_create( wbuffer_write_thread, wbuffer, 
@@ -237,7 +234,6 @@ wbuffer_new( Write *write )
 		wbuffer_free( wbuffer );
 		return( NULL );
 	}
-#endif /*HAVE_THREADS*/
 
 	return( wbuffer );
 }
@@ -266,13 +262,7 @@ wbuffer_flush( Write *write )
 
 	/* Set the background writer going for this buffer.
 	 */
-#ifdef HAVE_THREADS
 	vips_semaphore_up( &write->buf->go );
-#else
-	/* No threads? Write ourselves synchronously.
-	 */
-	wbuffer_write( write->buf );
-#endif /*HAVE_THREADS*/
 
 	return( 0 );
 }
diff --git a/libvips/iofuncs/sinkscreen.c b/libvips/iofuncs/sinkscreen.c
index 9b3153e4..753164f7 100644
--- a/libvips/iofuncs/sinkscreen.c
+++ b/libvips/iofuncs/sinkscreen.c
@@ -66,14 +66,6 @@
 #include <vips/thread.h>
 #include <vips/debug.h>
 
-/* A have-threads we can test in if().
- */
-#ifdef HAVE_THREADS
-static const int have_threads = 1;
-#else /*!HAVE_THREADS*/
-static const int have_threads = 0;
-#endif /*HAVE_THREADS*/
-
 #ifdef VIPS_DEBUG_AMBER
 static int render_num_renders = 0;
 #endif /*VIPS_DEBUG_AMBER*/
@@ -228,8 +220,8 @@ render_free( Render *render )
 	}
 	g_mutex_unlock( render_dirty_lock );
 
-	g_mutex_free( render->ref_count_lock );
-	g_mutex_free( render->lock );
+	vips_mutex_free( render->ref_count_lock );
+	vips_mutex_free( render->lock );
 
 	vips_slist_map2( render->all, (VipsSListMap2Fn) tile_free, NULL, NULL );
 	VIPS_FREEF( g_slist_free, render->all );
@@ -520,15 +512,12 @@ render_thread_main( void *client )
 static int
 render_thread_create( void )
 {
-	if( !have_threads )
-		return( 0 );
-
 	if( !render_dirty_lock ) {
-		render_dirty_lock = g_mutex_new();
+		render_dirty_lock = vips_mutex_new();
 		vips_semaphore_init( &render_dirty_sem, 0, "render_dirty_sem" );
 	}
 
-	if( !render_thread && have_threads ) {
+	if( !render_thread ) {
 		if( !(render_thread = g_thread_create_full( 
 			render_thread_main, NULL, 
 			VIPS__DEFAULT_STACK_SIZE, TRUE, FALSE, 
@@ -595,7 +584,7 @@ render_new( VipsImage *in, VipsImage *out, VipsImage *mask,
 		return( NULL );
 
 	render->ref_count = 1;
-	render->ref_count_lock = g_mutex_new();
+	render->ref_count_lock = vips_mutex_new();
 
 	render->in = in;
 	render->out = out;
@@ -607,7 +596,7 @@ render_new( VipsImage *in, VipsImage *out, VipsImage *mask,
 	render->notify = notify;
 	render->a = a;
 
-	render->lock = g_mutex_new();
+	render->lock = vips_mutex_new();
 
 	render->all = NULL;
 	render->ntiles = 0;
@@ -746,7 +735,7 @@ tile_queue( Tile *tile, VipsRegion *reg )
 	tile->painted = FALSE;
 	tile_touch( tile );
 
-	if( render->notify && have_threads ) {
+	if( render->notify ) {
 		/* Add to the list of renders with dirty tiles. The bg 
 		 * thread will pick it up and paint it. It can be already on
 		 * the dirty list.
@@ -755,7 +744,7 @@ tile_queue( Tile *tile, VipsRegion *reg )
 		render_dirty_put( render );
 	}
 	else {
-		/* No threads, or no notify ... paint the tile ourselves 
+		/* no notify ... paint the tile ourselves 
 		 * sychronously. No need to notify the client since they'll 
 		 * never see black tiles.
 		 */
@@ -968,7 +957,6 @@ image_stop( void *seq, void *a, void *b )
 static int
 mask_fill( VipsRegion *out, void *seq, void *a, void *b, gboolean *stop )
 {
-#ifdef HAVE_THREADS
 	Render *render = (Render *) a;
 	VipsRect *r = &out->valid;
 	int x, y;
@@ -1006,9 +994,6 @@ mask_fill( VipsRegion *out, void *seq, void *a, void *b, gboolean *stop )
 		}
 
 	g_mutex_unlock( render->lock );
-#else /*!HAVE_THREADS*/
-	vips_region_paint( out, &out->valid, 255 );
-#endif /*HAVE_THREADS*/
 
 	return( 0 );
 }
diff --git a/libvips/iofuncs/threadpool.c b/libvips/iofuncs/threadpool.c
index 19435c63..7588de05 100644
--- a/libvips/iofuncs/threadpool.c
+++ b/libvips/iofuncs/threadpool.c
@@ -101,25 +101,34 @@ int vips__thinstrip_height = VIPS__THINSTRIP_HEIGHT;
  */
 int vips__concurrency = 0;
 
-#ifndef HAVE_THREADS
-/* If we're building without gthread, we need stubs for the g_thread_*() and
- * g_mutex_*() functions. <vips/thread.h> has #defines which point the g_
- * names here.
+/* Glib 2.32 revised the thread API. We need some compat functions.
  */
 
-void vips__g_thread_init( GThreadFunctions *vtable ) {}
-gpointer vips__g_thread_join( GThread *dummy ) { return( NULL ); }
-gpointer vips__g_thread_self( void ) { return( NULL ); }
-GThread *vips__g_thread_create_full( GThreadFunc d1, 
-	gpointer d2, gulong d3, gboolean d4, gboolean d5, GThreadPriority d6,
-	GError **d7 )
-	{ return( NULL ); }
+GMutex *
+vips_mutex_new( void )
+{
+	GMutex *mutex;
 
-GMutex *vips__g_mutex_new( void ) { return( NULL ); }
-void vips__g_mutex_free( GMutex *d ) {}
-void vips__g_mutex_lock( GMutex *d ) {}
-void vips__g_mutex_unlock( GMutex *d ) {}
-#endif /*!HAVE_THREADS*/
+#ifdef HAVE_MUTEX_INIT
+	mutex = g_new( GMutex, 1 );
+	g_mutex_init( mutex );
+#else
+	mutex = g_mutex_new();
+#endif
+
+	return( mutex );
+}
+
+void
+vips_mutex_free( GMutex *mutex )
+{
+#ifdef HAVE_MUTEX_INIT
+	g_mutex_clear( mutex );
+	g_free( mutex );
+#else
+	g_mutex_free( mutex );
+#endif
+}
 
 /**
  * vips_concurrency_set:
@@ -564,7 +573,6 @@ vips_thread_work_unit( VipsThread *thr )
 	}
 }
 
-#ifdef HAVE_THREADS
 /* What runs as a thread ... loop, waiting to be told to do stuff.
  */
 static void *
@@ -592,7 +600,6 @@ vips_thread_main_loop( void *a )
 
         return( NULL );
 }
-#endif /*HAVE_THREADS*/
 
 /* Attach another thread to a threadpool.
  */
@@ -628,7 +635,6 @@ vips_thread_new( VipsThreadpool *pool )
 	}
 #endif /*TIME_THREAD*/
 
-#ifdef HAVE_THREADS
 	/* Make a worker thread. We have to use g_thread_create_full() because
 	 * we need to insist on a non-tiny stack. Some platforms default to
 	 * very small values (eg. various BSDs).
@@ -643,7 +649,6 @@ vips_thread_new( VipsThreadpool *pool )
 	}
 
 	VIPS_DEBUG_MSG_RED( "vips_thread_new: g_thread_create_full()\n" );
-#endif /*HAVE_THREADS*/
 
 	return( thr );
 }
@@ -674,7 +679,7 @@ vips_threadpool_free( VipsThreadpool *pool )
 		pool->im->filename, pool );
 
 	vips_threadpool_kill_threads( pool );
-	VIPS_FREEF( g_mutex_free, pool->allocate_lock );
+	VIPS_FREEF( vips_mutex_free, pool->allocate_lock );
 	vips_semaphore_destroy( &pool->finish );
 	vips_semaphore_destroy( &pool->tick );
 
@@ -699,7 +704,7 @@ vips_threadpool_new( VipsImage *im )
 	pool->im = im;
 	pool->allocate = NULL;
 	pool->work = NULL;
-	pool->allocate_lock = g_mutex_new();
+	pool->allocate_lock = vips_mutex_new();
 	pool->nthr = vips_concurrency_get();
 	pool->thr = NULL;
 	vips_semaphore_init( &pool->finish, 0, "finish" );
@@ -879,15 +884,9 @@ vips_threadpool_run( VipsImage *im,
 	}
 
 	for(;;) {
-#ifdef HAVE_THREADS
 		/* Wait for a tick from a worker.
 		 */
 		vips_semaphore_down( &pool->tick );
-#else
-		/* No threads, do the work ourselves in the main thread.
-		 */
-		vips_thread_work_unit( pool->thr[0] );
-#endif /*HAVE_THREADS*/
 
 		VIPS_DEBUG_MSG( "vips_threadpool_run: tick\n" );
 
diff --git a/libvips/mosaicing/im_lrmerge.c b/libvips/mosaicing/im_lrmerge.c
index 61f8495c..7149111e 100644
--- a/libvips/mosaicing/im_lrmerge.c
+++ b/libvips/mosaicing/im_lrmerge.c
@@ -680,7 +680,7 @@ lr_blend_labpack( REGION *or, MergeInfo *inf, Overlapping *ovlap, Rect *oreg )
 static void *
 lock_free( GMutex *lock )
 {
-	g_mutex_free( lock );
+	vips_mutex_free( lock );
 
 	return( NULL );
 }
@@ -767,10 +767,10 @@ im__build_mergestate( const char *domain,
 	for( x = 0; x < ovlap->flsize; x++ )
 		ovlap->first[x] = -1;
 
-	ovlap->fl_lock = g_mutex_new();
+	ovlap->fl_lock = vips_mutex_new();
 	if( im_add_close_callback( out, 
 		(im_callback_fn) lock_free, ovlap->fl_lock, NULL ) ) {
-		g_mutex_free( ovlap->fl_lock );
+		vips_mutex_free( ovlap->fl_lock );
 		return( NULL );
 	}