diff --git a/libvips/iofuncs/init.c b/libvips/iofuncs/init.c
index bcd1daab..eb8bbda9 100644
--- a/libvips/iofuncs/init.c
+++ b/libvips/iofuncs/init.c
@@ -291,13 +291,14 @@ set_stacksize( guint64 size )
 		return;
 	}
 
-	if( cur_stack_size < size )
+	if( cur_stack_size < size ) {
 		if( pthread_attr_setstacksize( &attr, size ) ||
 			pthread_setattr_default_np( &attr ) ) 
 			g_warning( "set_stacksize: unable to set stack size" );
 		else 
 			g_info( "set stack size to %" G_GUINT64_FORMAT "k", 
 				size / (guint64) 1024 );
+	}
 #endif /*HAVE_PTHREAD_DEFAULT_NP*/
 }
 
diff --git a/libvips/resample/thumbnail.c b/libvips/resample/thumbnail.c
index 84a58320..8d386e78 100644
--- a/libvips/resample/thumbnail.c
+++ b/libvips/resample/thumbnail.c
@@ -18,6 +18,8 @@
  * 	- implement shrink-on-load for tiff pyramid 
  * 3/2/19 kleisauke
  * 	- add option_string param to thumbnail_buffer
+ * 23/4/19
+ * 	- don't force import CMYK, since colourspace knows about it now
  */
 
 /*
@@ -567,17 +569,13 @@ vips_thumbnail_build( VipsObject *object )
 	}
 
 	/* In linear mode, we import right at the start. 
-	 *
-	 * We also have to import the whole image if it's CMYK, since
-	 * vips_colourspace() (see below) doesn't know about CMYK.
 	 *
 	 * This is only going to work for images in device space. If you have
 	 * an image in PCS which also has an attached profile, strange things
 	 * will happen. 
 	 */
 	have_imported = FALSE;
-	if( (thumbnail->linear ||
-		in->Type == VIPS_INTERPRETATION_CMYK) &&
+	if( thumbnail->linear &&
 		in->Coding == VIPS_CODING_NONE &&
 		(in->BandFmt == VIPS_FORMAT_UCHAR ||
 		 in->BandFmt == VIPS_FORMAT_USHORT) &&