Hi Eric, * Eric Blake wrote on Mon, May 25, 2009 at 02:52:37PM CEST: > According to Ralf Wildenhues on 5/24/2009 7:52 AM: > >> libtool 2.2.6a uses AC_LANG_SAVE/AC_LANG_RESTORE in libtool.m4. > >> These macros have been obsoleted by Autoconf. > >> > >> Could they be switched to LANG_PUSH/AC_LANG_POP in future releases? > > > > Not really; I don't think the latter provide equivalent functionality; > > at least, if memory serves correctly. > > In this case, there is nothing more to AC_LANG_SAVE/AC_LANG_RESTORE than > thin AU_DEFUN wrappers around AC_LANG_POP. They provide equivalent > functionality.
OK, I looked now. You can call AC_LANG_SAVE/AC_LANG_RESTORE without arguments, and the restore will do TRT, namely restoring the ac_ext, ac_compile and ac_link settings that we overwrote in the mean time. This is useful if the language you are moving to is not defined, such as Java and Windows Resource. I don't see how to do it with AC_LANG_PUSH without argument, or with one not known to Autoconf: configure.ac:189: error: AC_LANG: unknown language: ../../../autoconf/lib/autoconf/lang.m4:104: _AC_LANG_SET is expanded from... ../../../autoconf/lib/autoconf/lang.m4:120: AC_LANG_PUSH is expanded from... libltdl/m4/libtool.m4:6837: _LT_LANG_GCJ_CONFIG is expanded from... libltdl/m4/libtool.m4:814: _LT_LANG is expanded from... libltdl/m4/libtool.m4:797: LT_LANG is expanded from... configure.ac:189: the top level configure.ac:189: error: AC_LANG: unknown language: Java ../../../autoconf/lib/autoconf/lang.m4:104: _AC_LANG_SET is expanded from... ../../../autoconf/lib/autoconf/lang.m4:120: AC_LANG_PUSH is expanded from... libltdl/m4/libtool.m4:6837: _LT_LANG_GCJ_CONFIG is expanded from... libltdl/m4/libtool.m4:814: _LT_LANG is expanded from... libltdl/m4/libtool.m4:797: LT_LANG is expanded from... configure.ac:189: the top level Probably Libtool should define these languages, or Autoconf should? Thanks, Ralf
