diff --git a/indent/gitconfig.vim b/indent/gitconfig.vim
index 7d5d44b..f951c73 100644
--- a/indent/gitconfig.vim
+++ b/indent/gitconfig.vim
@@ -19,18 +19,30 @@ if exists("*GetGitconfigIndent")
   finish
 endif
 
+" The shiftwidth() exists since patch 7.3.694
+" Don't require it to exist.
+if exists('*shiftwidth')
+  function s:sw() abort
+    return shiftwidth()
+  endfunction
+else
+  function s:sw() abort
+    return &shiftwidth
+  endfunction
+endif
+
 function! GetGitconfigIndent()
   let line  = getline(prevnonblank(v:lnum-1))
   let cline = getline(v:lnum)
   if line =~  '\\\@<!\%(\\\\\)*\\$'
     " odd number of slashes, in a line continuation
-    return 2 * &sw
+    return 2 * s:sw()
   elseif cline =~ '^\s*\['
     return 0
   elseif cline =~ '^\s*\a'
-    return &sw
+    return s:sw()
   elseif cline == ''       && line =~ '^\['
-    return &sw
+    return s:sw()
   else
     return -1
   endif