diff --git a/src/charset.c b/src/charset.c
index b55468f..72838d0 100644
--- a/src/charset.c
+++ b/src/charset.c
@@ -771,7 +771,7 @@
     chartabsize_T cts;
 
     init_chartabsize_arg(&cts, wp, lnum, 0, line, line);
-    cts.cts_with_trailing = len = MAXCOL;
+    cts.cts_with_trailing = len == MAXCOL;
     for ( ; *cts.cts_ptr != NUL && (len == MAXCOL || cts.cts_ptr < line + len);
 						      MB_PTR_ADV(cts.cts_ptr))
 	cts.cts_vcol += win_lbr_chartabsize(&cts, NULL);