I am not sure why, but the regular expression "(?:\^\{\})" gets
rendered by asciidoc as "(?:\{})". The intent seems to be a regex
matching the literal string "^{}", so this rewrites the markup to
produce "(?:\^{})" as output.
Cc: Julian Phillips <julian@quantumfyre.co.uk> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>