Add icons in the fringe, for flymake

flymake-fringe-icons.el

(require 'fringe-helper)
(require 'flymake)

(defvar flymake-fringe-overlays nil)
(make-variable-buffer-local 'flymake-fringe-overlays)

(defadvice flymake-make-overlay (after add-to-fringe first
                                       (beg end tooltip-text face mouse-face)
                                       activate compile)
  (push (fringe-helper-insert-region
         beg end
         (fringe-lib-load (if (eq face 'flymake-errline)
                              fringe-lib-exclamation-mark
                            fringe-lib-question-mark))
         'left-fringe 'font-lock-warning-face)
        flymake-fringe-overlays))

(defadvice flymake-delete-own-overlays (after remove-from-fringe activate
                                              compile)
  (mapc 'fringe-helper-remove flymake-fringe-overlays)
  (setq flymake-fringe-overlays nil))

(provide 'flymake-fringe-icons)