diff --git a/lisp/ox-html.el b/lisp/ox-html.el
index bd3e43faa..e16e0747a 100644
--- a/lisp/ox-html.el
+++ b/lisp/ox-html.el
@@ -2446,15 +2446,17 @@ CONTENTS is nil. INFO is a plist holding contextual information."
;;;; Latex Environment
(defun org-html-format-latex (latex-frag processing-type)
- "Format the LaTeX fragment LATEX-FRAG into HTML."
- (let ((cache-relpath "") (cache-dir "") bfn)
+ "Format a LaTeX fragment LATEX-FRAG into HTML."
+ (let ((cache-relpath "") (cache-dir ""))
(unless (eq processing-type 'mathjax)
- (setq bfn (buffer-file-name)
- cache-relpath
- (concat "ltxpng/"
- (file-name-sans-extension
- (file-name-nondirectory bfn)))
- cache-dir (file-name-directory bfn)))
+ (let ((bfn (or (buffer-file-name)
+ (make-temp-name
+ (expand-file-name "latex" temporary-file-directory)))))
+ (setq cache-relpath
+ (concat "ltxpng/"
+ (file-name-sans-extension
+ (file-name-nondirectory bfn)))
+ cache-dir (file-name-directory bfn))))
(with-temp-buffer
(insert latex-frag)
(org-format-latex cache-relpath cache-dir nil "Creating LaTeX Image..."