diff --git a/src/p_mobj.c b/src/p_mobj.c
index 16969db59..f3d3de5ec 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -7979,7 +7979,7 @@ void P_MobjThinker(mobj_t *mobj)
 					    || goalpost->movefactor != mobj->z
 						|| goalpost->friction != mobj->height
 						|| flipchanged
-						|| goalpost->threshold != (mobj->flags & (MF_SLIDEME | MF_GRENADEBOUNCE)))
+						|| goalpost->threshold != (INT32)(mobj->flags & (MF_SLIDEME | MF_GRENADEBOUNCE)))
 					{
 						goalpost->destscale = sparkle->destscale = droneman->destscale = mobj->destscale;