##### http://autoconf-archive.cryp.to/patch_libtool_on_darwin_zsh_overquoting.html
#
# OBSOLETE MACRO
#
#   The problem is fixed in modern libtool versions.
#
# SYNOPSIS
#
#   PATCH_LIBTOOL_ON_DARWIN_ZSH_OVERQUOTING
#
# DESCRIPTION
#
#   libtool 1.4.x has a bug on darwin where the "zsh" is installed as
#   the bourne shell replacement. Of course, the zsh is called in a
#   compatibility mode but there is a common problem with it, probably
#   a bug of zsh. Newer darwin systems have a "bash" installed now, but
#   the configure-default will be "zsh" in most systems still.
#
#   The bug revelas itself as an overquoted statement in the libtool
#   cmds-spec for sharedlib creation on testing for "module" builds.
#   Later libtool has gone rid of it by simply removing the quotes at
#   that point . Here we maintain the original style and simply remove
#   the extra escape character, i.e. we look for "archive_cmds" and
#   replace a sequence of triple-backslash-and-doublequote with
#   single-backslash-and-doublequote.
#
# LAST MODIFICATION
#
#   2006-10-13
#
# COPYLEFT
#
#   Copyright (c) 2006 Guido U. Draheim <guidod@gmx.de>
#
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#
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#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
#   General Public License for more details.
#
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AC_DEFUN([PATCH_LIBTOOL_ON_DARWIN_ZSH_OVERQUOTING],
[# libtool-1.4 specific, on zsh target the final requoting does one too much
case "$host_os" in
  darwin*)
    if grep "1.92" libtool >/dev/null ; then
AC_MSG_RESULT(patching libtool on .so-sharedlib creation (zsh overquoting))
      test -f libtool.old || (mv libtool libtool.old && cp libtool.old libtool)
      sed -e '/archive_cmds=/s:[[\\]][[\\]][[\\]]*":\\":g' libtool >libtool.new
      (test -s libtool.new || rm libtool.new) 2>/dev/null
      test -f libtool.new && mv libtool.new libtool # not 2>/dev/null !!
      test -f libtool     || mv libtool.old libtool
    fi
  ;;
esac
])