Use of double parentheses

[Julien ÉLIE]

Hi all,

Reading a generated "configure" file, I see:

# Unset variables that we do not need and which cause bugs (e.g. in
# pre-3.0 UWIN ksh).  But do not cause bugs in bash 2.01; the "|| exit 1"
# suppresses any "Segmentation fault" message there.  '((' could
# trigger a bug in pdksh 5.2.14.
for as_var in BASH_ENV ENV MAIL MAILPATH
do eval test x\${$as_var+set} = xset \
  && ( (unset $as_var) || exit 1) >/dev/null 2>&1 && unset $as_var || :
done


Wouldn't it mean that all '((' present in the "configure" script, and
related to shell commands, should be rewritten to '( ('?

-- 
Julien ÉLIE

« Un ami fidèle qui parle très bien votre langue et toutes les
  langues vivantes : le latin, le grec, le celte, etc. » (Astérix)