diff --git a/autoload/sign.vim b/autoload/sign.vim
index 44725eb..4e8f738 100644
--- a/autoload/sign.vim
+++ b/autoload/sign.vim
@@ -28,8 +28,8 @@ function! sign#find_other_signs(file_name)
   redir END
   let s:other_signs = []
   for sign_line in split(signs, '\n')
-    if sign_line =~ '^\s\+\w\+='
-      let matches = matchlist(sign_line, '^\s\+\w\+=\(\d\+\)')
+    let matches = matchlist(sign_line, '^\s\+\w\+=\(\d\+\)')
+    if len(matches) > 0
       let line_number = str2nr(matches[1])
       call add(s:other_signs, line_number)
     endif