diff --git a/autoload/airline/extensions.vim b/autoload/airline/extensions.vim
index 2f1f5f2..1f8a919 100644
--- a/autoload/airline/extensions.vim
+++ b/autoload/airline/extensions.vim
@@ -32,7 +32,7 @@ function! airline#extensions#apply_left_override(section1, section2)
 endfunction
 
 let s:active_winnr = -1
-function! airline#extensions#update_statusline()
+function! airline#extensions#update_statusline(...)
   let s:active_winnr = winnr()
 
   if &buftype == 'quickfix'
@@ -65,7 +65,7 @@ function! airline#extensions#update_statusline()
   endfor
 endfunction
 
-function! airline#extensions#is_excluded_window()
+function! airline#extensions#is_excluded_window(...)
   for matchft in g:airline_exclude_filetypes
     if matchft ==# &ft
       return 1
@@ -165,7 +165,7 @@ function! airline#extensions#load()
     endif
 
     if (get(g:, 'airline#extensions#whitespace#enabled', 1) && get(g:, 'airline_detect_whitespace', 1))
-      call airline#extensions#whitespace#init()
+      call airline#extensions#whitespace#init(s:ext)
     endif
   endif
 
diff --git a/autoload/airline/extensions/bufferline.vim b/autoload/airline/extensions/bufferline.vim
index c95cdf3..a6b9848 100644
--- a/autoload/airline/extensions/bufferline.vim
+++ b/autoload/airline/extensions/bufferline.vim
@@ -1,7 +1,7 @@
 " MIT License. Copyright (c) 2013 Bailey Ling.
-" vim: ts=2 sts=2 sw=2 fdm=indent
+" vim: et ts=2 sts=2 sw=2
 
-function! airline#extensions#bufferline#apply()
+function! airline#extensions#bufferline#apply(...)
   " revert to default in non-active splits
   for nr in filter(range(1, winnr('$')), 'v:val != winnr()')
     if matchstr(getwinvar(nr, '&statusline'), '%{bufferline') != ''
diff --git a/autoload/airline/extensions/commandt.vim b/autoload/airline/extensions/commandt.vim
index ac74aff..644cc66 100644
--- a/autoload/airline/extensions/commandt.vim
+++ b/autoload/airline/extensions/commandt.vim
@@ -1,7 +1,7 @@
-" MIT license. Copyright (c) 2013 Bailey Ling.
-" vim: ts=2 sts=2 sw=2 fdm=indent
+" MIT License. Copyright (c) 2013 Bailey Ling.
+" vim: et ts=2 sts=2 sw=2
 
-function! airline#extensions#commandt#apply()
+function! airline#extensions#commandt#apply(...)
   if bufname('%') ==# 'GoToFile'
     call airline#extensions#apply_left_override('CommandT', '')
   endif
diff --git a/autoload/airline/extensions/csv.vim b/autoload/airline/extensions/csv.vim
index 6f0087c..d669be8 100644
--- a/autoload/airline/extensions/csv.vim
+++ b/autoload/airline/extensions/csv.vim
@@ -14,7 +14,7 @@ function! airline#extensions#csv#get_column()
   return ''
 endfunction
 
-function! airline#extensions#csv#apply()
+function! airline#extensions#csv#apply(...)
   if &ft ==# "csv"
     if !exists('w:airline_section_gutter')
       let w:airline_section_gutter = '%='
diff --git a/autoload/airline/extensions/ctrlp.vim b/autoload/airline/extensions/ctrlp.vim
index 3744548..8f30e2d 100644
--- a/autoload/airline/extensions/ctrlp.vim
+++ b/autoload/airline/extensions/ctrlp.vim
@@ -1,5 +1,5 @@
-" MIT license. Copyright (c) 2013 Bailey Ling.
-" vim: ts=2 sts=2 sw=2 fdm=indent
+" MIT License. Copyright (c) 2013 Bailey Ling.
+" vim: et ts=2 sts=2 sw=2
 
 let s:color_template = get(g:, 'airline#extensions#ctrlp#color_template', 'insert')
 
@@ -49,7 +49,7 @@ function! airline#extensions#ctrlp#ctrlp_airline_status(...)
   return len.dir
 endfunction
 
-function! airline#extensions#ctrlp#is_statusline_overwritten()
+function! airline#extensions#ctrlp#is_statusline_overwritten(...)
   return match(&statusline, 'CtrlPlight') >= 0
 endfunction
 
@@ -60,3 +60,4 @@ function! airline#extensions#ctrlp#init(ext)
         \ }
   call a:ext.add_cursormove_funcref(function('airline#extensions#ctrlp#is_statusline_overwritten'))
 endfunction
+
diff --git a/autoload/airline/extensions/example.vim b/autoload/airline/extensions/example.vim
index d928120..637f83d 100644
--- a/autoload/airline/extensions/example.vim
+++ b/autoload/airline/extensions/example.vim
@@ -1,5 +1,5 @@
 " MIT License. Copyright (c) 2013 Bailey Ling.
-" vim: ts=2 sts=2 sw=2 fdm=indent
+" vim: et ts=2 sts=2 sw=2
 
 " Extension specific variables can be defined the usual fashion.
 if !exists('g:airline#extensions#example#number_of_cats')
@@ -23,7 +23,7 @@ function! airline#extensions#example#init(ext)
   let g:airline_section_y .= '%{airline#extensions#example#nyancat()}'
 endfunction
 
-function! airline#extensions#example#apply()
+function! airline#extensions#example#apply(...)
   " Here we are checking for the filetype, allowing for the extension to
   " be loaded only in certain cases.
   if &filetype == "nyancat"
diff --git a/autoload/airline/extensions/iminsert.vim b/autoload/airline/extensions/iminsert.vim
index 5357cad..9371016 100644
--- a/autoload/airline/extensions/iminsert.vim
+++ b/autoload/airline/extensions/iminsert.vim
@@ -1,5 +1,5 @@
-" MIT license. Copyright (c) 2013 Bailey Ling.
-" vim: ts=2 sts=2 sw=2 fdm=indent
+" MIT License. Copyright (c) 2013 Bailey Ling.
+" vim: et ts=2 sts=2 sw=2
 
 function! airline#extensions#iminsert#get_text()
   if &iminsert
diff --git a/autoload/airline/extensions/syntastic.vim b/autoload/airline/extensions/syntastic.vim
index ff4e6a6..21ec0d8 100644
--- a/autoload/airline/extensions/syntastic.vim
+++ b/autoload/airline/extensions/syntastic.vim
@@ -1,7 +1,8 @@
 " MIT License. Copyright (c) 2013 Bailey Ling.
 " vim: et ts=2 sts=2 sw=2
 
-function! airline#extensions#syntastic#apply()
+function! airline#extensions#syntastic#apply(...)
+  let w:airline_section_warning = get(w:, 'airline_section_warning', '')
   let w:airline_section_warning = ' %{SyntasticStatuslineFlag()}'
 endfunction
 
diff --git a/autoload/airline/extensions/tagbar.vim b/autoload/airline/extensions/tagbar.vim
index 66f80ea..3326e49 100644
--- a/autoload/airline/extensions/tagbar.vim
+++ b/autoload/airline/extensions/tagbar.vim
@@ -1,7 +1,7 @@
 " MIT License. Copyright (c) 2013 Bailey Ling.
-" vim: ts=2 sts=2 sw=2 fdm=indent
+" vim: et ts=2 sts=2 sw=2
 
-function! airline#extensions#tagbar#apply()
+function! airline#extensions#tagbar#apply(...)
   if &ft == 'tagbar'
     call airline#extensions#apply_left_override('Tagbar', '%{TagbarGenerateStatusline()}')
   endif
diff --git a/autoload/airline/extensions/undotree.vim b/autoload/airline/extensions/undotree.vim
index b8dfe49..f869d0c 100644
--- a/autoload/airline/extensions/undotree.vim
+++ b/autoload/airline/extensions/undotree.vim
@@ -1,7 +1,7 @@
 " MIT License. Copyright (c) 2013 Bailey Ling.
 " vim: et ts=2 sts=2 sw=2
 
-function! airline#extensions#undotree#apply()
+function! airline#extensions#undotree#apply(...)
   if exists('t:undotree')
     if &ft == 'undotree' && exists('*t:undotree.GetStatusLine')
       call airline#extensions#apply_left_override('undo', '%{t:undotree.GetStatusLine()}')
diff --git a/autoload/airline/extensions/whitespace.vim b/autoload/airline/extensions/whitespace.vim
index 0e21a42..b108a4b 100644
--- a/autoload/airline/extensions/whitespace.vim
+++ b/autoload/airline/extensions/whitespace.vim
@@ -1,5 +1,5 @@
 " MIT License. Copyright (c) 2013 Bailey Ling.
-" vim: ts=2 sts=2 sw=2 fdm=indent
+" vim: et ts=2 sts=2 sw=2
 
 " http://got-ravings.blogspot.com/2008/10/vim-pr0n-statusline-whitespace-flags.html
 
@@ -53,7 +53,7 @@ function! airline#extensions#whitespace#check()
   return b:airline_whitespace_check
 endfunction!
 
-function! airline#extensions#whitespace#apply()
+function! airline#extensions#whitespace#apply(...)
   if !exists('w:airline_section_warning')
     let w:airline_section_warning = ' '
   endif
@@ -70,10 +70,10 @@ function! airline#extensions#whitespace#toggle()
   endif
 endfunction
 
-function! airline#extensions#whitespace#init()
+function! airline#extensions#whitespace#init(ext)
   if !s:initialized
     let s:initialized = 1
-    call add(g:airline_statusline_funcrefs, function('airline#extensions#whitespace#apply'))
+    call a:ext.add_statusline_funcref(function('airline#extensions#whitespace#apply'))
   endif
 
   unlet! b:airline_whitespace_check
diff --git a/autoload/airline/util.vim b/autoload/airline/util.vim
index c60249e..b63898e 100644
--- a/autoload/airline/util.vim
+++ b/autoload/airline/util.vim
@@ -13,7 +13,7 @@ else
 endif
 
 if v:version >= 704
-  function! airline#util#exec_funcrefs(list, break_early)
+  function! airline#util#exec_funcrefs(list, break_early, ...)
     for Fn in a:list
       if a:break_early
         if Fn()
@@ -25,7 +25,7 @@ if v:version >= 704
     endfor
   endfunction
 else
-  function! airline#util#exec_funcrefs(list, break_early)
+  function! airline#util#exec_funcrefs(list, break_early, ...)
     " for 7.2; we cannot iterate the list, hence why we use range()
     " for 7.3-[97, 328]; we cannot reuse the variable, hence the {}
     for i in range(0, len(a:list) - 1)
diff --git a/doc/airline.txt b/doc/airline.txt
index a0871f7..995f053 100644
--- a/doc/airline.txt
+++ b/doc/airline.txt
@@ -104,7 +104,7 @@ COMMANDS                                                  *airline-commands*
   Toggles whitespace detection.
 
 :AirlineToggle                                              *:AirlineToggle*
-  Toggles between the standard `statusline` or airline.
+  Toggles between the standard `statusline`
 
 ==============================================================================
 CUSTOMIZATION                                        *airline-customization*
@@ -249,7 +249,7 @@ The g:airline_statusline_funcrefs variable is an array of funcrefs that get
 invoked before the statusline gets overwritten for each window.  The following
 is an example of how you can extend vim-airline to support a new plugin.
 >
-  function! MyPlugin()
+  function! MyPlugin(...)
     if &filetype == 'MyPluginFileType'
       let w:airline_section_a = 'MyPlugin'
       let w:airline_section_b = '%f'