diff --git a/src/backends/meta-monitor-transform.h b/src/backends/meta-monitor-transform.h
index 6fca0a4e3fbb2aabe899b4dcc4777116ee0c3d63..e5757e8694541ce7ec0b3e4a22e51452a158ac62 100644
--- a/src/backends/meta-monitor-transform.h
+++ b/src/backends/meta-monitor-transform.h
@@ -49,7 +49,7 @@ meta_monitor_transform_is_rotated (MetaMonitorTransform transform)
 static inline gboolean
 meta_monitor_transform_is_flipped (MetaMonitorTransform transform)
 {
-  return (abs(transform) >= META_MONITOR_TRANSFORM_FLIPPED);
+  return (transform >= META_MONITOR_TRANSFORM_FLIPPED);
 }
 
 MetaMonitorTransform meta_monitor_transform_invert (MetaMonitorTransform transform);
diff --git a/src/tests/monitor-transform-tests.c b/src/tests/monitor-transform-tests.c
index 91ce985beb3e1f4261d73631d2548b4582bb5b43..fb505d00c8a77f6c5cb31469df7eabe369c96d5d 100644
--- a/src/tests/monitor-transform-tests.c
+++ b/src/tests/monitor-transform-tests.c
@@ -62,22 +62,22 @@ test_transform (void)
     },
     {
       .transform = META_MONITOR_TRANSFORM_NORMAL,
-      .other = -META_MONITOR_TRANSFORM_90,
+      .other = META_MONITOR_TRANSFORM_270,
       .expect = META_MONITOR_TRANSFORM_270,
     },
     {
       .transform = META_MONITOR_TRANSFORM_FLIPPED,
-      .other = -META_MONITOR_TRANSFORM_90,
+      .other = META_MONITOR_TRANSFORM_270,
       .expect = META_MONITOR_TRANSFORM_FLIPPED_270,
     },
     {
       .transform = META_MONITOR_TRANSFORM_FLIPPED_180,
-      .other = -META_MONITOR_TRANSFORM_270,
+      .other = META_MONITOR_TRANSFORM_90,
       .expect = META_MONITOR_TRANSFORM_FLIPPED_270,
     },
     {
       .transform = META_MONITOR_TRANSFORM_FLIPPED_180,
-      .other = -META_MONITOR_TRANSFORM_FLIPPED_180,
+      .other = META_MONITOR_TRANSFORM_FLIPPED_180,
       .expect = META_MONITOR_TRANSFORM_NORMAL,
     },
   };