diff --git a/README.md b/README.md
index b60af699..654c0e21 100644
--- a/README.md
+++ b/README.md
@@ -44,7 +44,7 @@ Static analysis with:
 
 Leak check:
 
-        $ export G_DEBUG=gc-friendly
+	$ export G_DEBUG=gc-friendly
 	$ export G_SLICE=always-malloc
 	$ valgrind --suppressions=/home/john/nip2.supp \
 		--leak-check=yes \
diff --git a/libvips/include/vips/internal.h b/libvips/include/vips/internal.h
index b21c837c..ddf7798e 100644
--- a/libvips/include/vips/internal.h
+++ b/libvips/include/vips/internal.h
@@ -71,6 +71,10 @@ extern int vips__concurrency;
  */
 extern int vips__fatal;
 
+/* Enable leak check.
+ */
+extern int vips__leak;
+
 /* Give progress feedback.
  */
 extern int vips__progress;
diff --git a/libvips/iofuncs/init.c b/libvips/iofuncs/init.c
index ebdbd634..a1467444 100644
--- a/libvips/iofuncs/init.c
+++ b/libvips/iofuncs/init.c
@@ -96,7 +96,7 @@ static char *vips__argv0 = NULL;
 
 /* Leak check on exit.
  */
-static int vips__leak = 0;
+int vips__leak = 0;
 
 /**
  * vips_get_argv0:
diff --git a/libvips/iofuncs/type.c b/libvips/iofuncs/type.c
index f9bc0f3e..84ecf351 100644
--- a/libvips/iofuncs/type.c
+++ b/libvips/iofuncs/type.c
@@ -5,6 +5,8 @@
  *
  * 27/10/11
  * 	- from header.c
+ * 16/7/13
+ * 	- leakcheck VipsArea
  */
 
 /*
@@ -141,9 +143,7 @@ vips_thing_get_type( void )
  * strings. 
  */
 
-#ifdef DEBUG
 static GSList *vips_area_all = NULL;
-#endif /*DEBUG*/
 
 VipsArea *
 vips_area_copy( VipsArea *area )
@@ -174,9 +174,11 @@ vips_area_unref( VipsArea *area )
 
 #ifdef DEBUG
 	printf( "vips_area_unref: %p count = %d\n", area, area->count );
-	g_assert( g_slist_find( vips_area_all, area ) ); 
 #endif /*DEBUG*/
 
+	if( vips__leak )
+		g_assert( g_slist_find( vips_area_all, area ) ); 
+
 	if( area->count == 0 ) {
 		if( area->free_fn && area->data ) {
 			area->free_fn( area->data, area );
@@ -190,8 +192,10 @@ vips_area_unref( VipsArea *area )
 
 		g_free( area );
 
+		if( vips__leak )
+			vips_area_all = g_slist_remove( vips_area_all, area ); 
+
 #ifdef DEBUG
-		vips_area_all = g_slist_remove( vips_area_all, area ); 
 		printf( "vips_area_unref: free .. total = %d\n", 
 			g_slist_length( vips_area_all ) );
 #endif /*DEBUG*/
@@ -226,8 +230,10 @@ vips_area_new( VipsCallbackFn free_fn, void *data )
 	area->type = 0;
 	area->sizeof_type = 0;
 
+	if( vips__leak )
+		vips_area_all = g_slist_prepend( vips_area_all, area ); 
+
 #ifdef DEBUG
-	vips_area_all = g_slist_prepend( vips_area_all, area ); 
 	printf( "vips_area_new: %p count = %d (%d in total)\n", 
 		area, area->count, 
 		g_slist_length( vips_area_all ) );
@@ -239,7 +245,6 @@ vips_area_new( VipsCallbackFn free_fn, void *data )
 void
 vips__type_leak( void )
 {
-#ifdef DEBUG
 	if( vips_area_all ) {
 		GSList *p; 
 
@@ -251,7 +256,6 @@ vips__type_leak( void )
 		}
 		printf( "%d in total\n", g_slist_length( vips_area_all ) );
 	}
-#endif /*DEBUG*/
 }
 
 /**