diff --git a/source/build/src/clip.cpp b/source/build/src/clip.cpp
index e0d8a6a23..34e224e19 100644
--- a/source/build/src/clip.cpp
+++ b/source/build/src/clip.cpp
@@ -1663,7 +1663,7 @@ int pushmove(vec3_t *const vect, int16_t *const sectnum,
                         bad = -1;
                         k--; if (k <= 0) return bad;
                         clipupdatesector(vect->vec2, sectnum, walldist);
-                        if (*sectnum < 0) return -1;
+                        if (enginecompatibility_mode == ENGINECOMPATIBILITY_NONE && *sectnum < 0) return -1;
                     }
                     else if (bitmap_test(clipsectormap, wal->nextsector) == 0)
                         addclipsect(wal->nextsector);