Subject: bug#18522: 24.4.50; mapcar is very slow

From: Peter Münster <[email-masked]>
Date: Sun, 21 Feb 2016 15:36:21 +0100

The problem seems to be string-match:

(defun my-parse-time-string-test ()
  (let (case-fold-search)
    (string-match "x" "x")))

(let ((gc-cons-threshold most-positive-fixnum))
  (benchmark-run 1
    (dotimes (i 100000) (my-parse-time-string-test))))

Fast emacs: (0.094749241 0 0.0)
Slow emacs: (1.802927531 0 0.0)

-- 
           Peter