When trying to build tor master we get the following error, when running `./autogen.sh`: ``` configure.ac:1811: warning: The macro `AC_WARN' is obsolete. configure.ac:1811: You should run autoupdate. ../../lib/autoconf/oldnames.m4:33: AC_WARN is expanded from... ../../lib/m4sugar/m4sh.m4:550: AS_CASE is expanded from... configure.ac:1811: the top level configure.ac:1811: warning: The macro `AC_WARN' is obsolete. configure.ac:1811: You should run autoupdate. ../../lib/autoconf/oldnames.m4:33: AC_WARN is expanded from... ../../lib/m4sugar/m4sh.m4:550: AS_CASE is expanded from... configure.ac:1811: the top level autoreconf: /usr/bin/autoconf failed with exit status: 1 ``` It seems related to commit `abde9fb426c7d6d0dbdaccc724c3b4257d99ad30` from legacy/trac#20424. I am getting this error with autoconf 2.69-8.