diff --git a/src/fold.c b/src/fold.c
index bb7b8b7..a28a874 100644
--- a/src/fold.c
+++ b/src/fold.c
@@ -2971,7 +2971,11 @@
     else
 	flp->lvl = get_indent_buf(buf, lnum) / buf->b_p_sw;
     if (flp->lvl > flp->wp->w_p_fdn)
+    {
 	flp->lvl = flp->wp->w_p_fdn;
+	if (flp->lvl < 0)
+	    flp->lvl = 0;
+    }
 }
 
 /* foldlevelDiff() {{{2 */
diff --git a/src/syntax.c b/src/syntax.c
index 1b09e70..d5047c7 100644
--- a/src/syntax.c
+++ b/src/syntax.c
@@ -6072,7 +6072,11 @@
 		++level;
     }
     if (level > wp->w_p_fdn)
+    {
 	level = wp->w_p_fdn;
+	if (level < 0)
+	    level = 0;
+    }
     return level;
 }
 #endif
diff --git a/src/version.c b/src/version.c
index fe3ea42..6e5b5df 100644
--- a/src/version.c
+++ b/src/version.c
@@ -667,6 +667,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    154,
+/**/
     153,
 /**/
     152,