diff --git a/ChangeLog b/ChangeLog
index 2dac665b..b87946ce 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -6,6 +6,8 @@
 
 18/10/16 started 8.4.3
 - fix error detection in gif_close, thanks aaron42net
+- fix tiny threading memleak
+- improve compatibility with very old glib, see #548
 
 27/9/16 started 8.4.2
 - small doc improvements
diff --git a/libvips/conversion/bandbool.c b/libvips/conversion/bandbool.c
index 86385048..d26c5d7d 100644
--- a/libvips/conversion/bandbool.c
+++ b/libvips/conversion/bandbool.c
@@ -186,7 +186,7 @@ vips_bandbool_buffer( VipsBandary *bandary,
 #define D VIPS_FORMAT_DOUBLE
 #define DX VIPS_FORMAT_DPCOMPLEX
 
-/* Type conversions for boolean. 
+/* Format conversions for boolean. 
  */
 static const VipsBandFormat vips_bandbool_format_table[10] = {
 /* UC  C   US  S   UI  I   F   X   D   DX */
diff --git a/libvips/include/vips/internal.h b/libvips/include/vips/internal.h
index e88f1eb3..1fa940a1 100644
--- a/libvips/include/vips/internal.h
+++ b/libvips/include/vips/internal.h
@@ -104,6 +104,8 @@ extern gboolean vips__cache_trace;
 
 extern int vips__n_active_threads;
 
+void vips__threadpool_init( void );
+
 void vips__cache_init( void );
 
 void vips__print_renders( void );
diff --git a/libvips/iofuncs/buffer.c b/libvips/iofuncs/buffer.c
index e315b5ce..8338468e 100644
--- a/libvips/iofuncs/buffer.c
+++ b/libvips/iofuncs/buffer.c
@@ -652,7 +652,7 @@ buffer_thread_destroy_notify( VipsBufferThread *buffer_thread )
 	buffer_thread_free( buffer_thread );
 }
 
-/* Init the buffer cache system. This must only be called from worker threads.
+/* Init the buffer cache system. This is called during vips_init.
  */
 void
 vips__buffer_init( void )
diff --git a/libvips/iofuncs/init.c b/libvips/iofuncs/init.c
index a0ea934e..5650be42 100644
--- a/libvips/iofuncs/init.c
+++ b/libvips/iofuncs/init.c
@@ -302,6 +302,9 @@ vips_init( const char *argv0 )
 		g_thread_init( NULL );
 #endif 
 
+	vips__threadpool_init();
+	vips__buffer_init();
+
 	/* This does an unsynchronised static hash table init on first call --
 	 * we have to make sure we do this single-threaded. See: 
 	 * https://github.com/openslide/openslide/issues/161
diff --git a/libvips/iofuncs/threadpool.c b/libvips/iofuncs/threadpool.c
index 7592bd9c..577309dd 100644
--- a/libvips/iofuncs/threadpool.c
+++ b/libvips/iofuncs/threadpool.c
@@ -106,7 +106,7 @@ int vips__n_active_threads = 0;
 
 /* Set this GPrivate to indicate that this is a vips worker.
  */
-static GPrivate vips_threadpool_is_worker_private;
+static GPrivate *is_worker_key = NULL;
 
 /* Glib 2.32 revised the thread API. We need some compat functions.
  */
@@ -170,7 +170,7 @@ vips_g_cond_free( GCond *cond )
 gboolean
 vips_thread_isworker( void )
 {
-	return( g_private_get( &vips_threadpool_is_worker_private ) != NULL );
+	return( g_private_get( is_worker_key ) != NULL );
 }
 
 typedef struct {
@@ -188,7 +188,10 @@ vips_thread_run( gpointer data )
 
 	/* Set this to something (anything) to tag this thread as a vips worker.
 	 */
-	g_private_set( &vips_threadpool_is_worker_private, data );
+	g_private_set( is_worker_key, data );
+
+	if( vips__thread_profile ) 
+		vips__thread_profile_attach( info->domain );
 
 	if( vips__thread_profile ) 
 		vips__thread_profile_attach( info->domain );
@@ -996,6 +999,23 @@ vips_threadpool_run( VipsImage *im,
 	return( result );
 }
 
+/* Start up threadpools. This is called during vips_init.
+ */
+void
+vips__threadpool_init( void )
+{
+	/* We need to work with the pre-2.32 threading API.
+	 */
+#ifdef HAVE_PRIVATE_INIT
+	static GPrivate private = { 0 }; 
+
+	is_worker_key = &private;
+#else
+	if( !is_worker_key ) 
+		is_worker_key = g_private_new( NULL ); 
+#endif
+}
+
 /**
  * vips_get_tile_size:
  * @im: image to guess for
diff --git a/test/test_foreign.py b/test/test_foreign.py
index 5698793c..c6d0eba0 100755
--- a/test/test_foreign.py
+++ b/test/test_foreign.py
@@ -58,9 +58,13 @@ class TestForeign(unittest.TestCase):
 
         self.colour = Vips.Image.jpegload(self.jpeg_file)
         self.mono = self.colour.extract_band(1)
+        # we remove the ICC profile: the RGB one will no longer be appropriate
+        self.mono.remove("icc-profile-data")
         self.rad = self.colour.float2rad()
+        self.rad.remove("icc-profile-data")
         self.cmyk = self.colour.bandjoin(self.mono)
         self.cmyk = self.cmyk.copy(interpretation = Vips.Interpretation.CMYK)
+        self.cmyk.remove("icc-profile-data")
 
         im = Vips.Image.new_from_file(self.gif_file)
         self.onebit = im > 128