title: AS_IF and AC_MSG_ERROR: error: possibly undefined macro
body: <p>I encounter such errors when trying to build libnice-0.1.10. For solution, I am following <a href="https://stackoverflow.com/questions/8811381/possibly-undefined-macro-ac-msg-error">possibly undefined macro: AC_MSG_ERROR</a>, but still not getting there.</p>
  <p>some program version</p>
  <pre><code>uname: 3.5.0-23-generic
  m4: 1.4.16
  automake: 1.14.1
  autoconf: 2.69
  libtoolize: 2.4.2
  </code></pre>
  <p>I also add <code>ACLOCAL_FLAGS=&quot;-I /.../share/aclocal&quot;</code> in <code>~/.bashrc</code>.</p>
  <p>Here is what is reported from <code>autogen.sh</code>.</p>
  <pre><code>$ ./autogen.sh
  configure.ac:331: warning: PKG_PROG_PKG_CONFIG is m4_require'd but not m4_defun'd
  m4/gtk-doc.m4:7: GTK_DOC_CHECK is expanded from...
  configure.ac:331: the top level
  configure.ac:331: warning: PKG_PROG_PKG_CONFIG is m4_require'd but not m4_defun'd
  m4/gtk-doc.m4:7: GTK_DOC_CHECK is expanded from...
  configure.ac:331: the top level
  configure.ac:331: warning: PKG_PROG_PKG_CONFIG is m4_require'd but not m4_defun'd
  m4/gtk-doc.m4:7: GTK_DOC_CHECK is expanded from...
  configure.ac:331: the top level
  libtoolize: putting auxiliary files in `.'.
  libtoolize: copying file `./ltmain.sh'
  libtoolize: putting macros in AC_CONFIG_MACRO_DIR, `m4'.
  libtoolize: copying file `m4/libtool.m4'
  libtoolize: copying file `m4/ltoptions.m4'
  libtoolize: copying file `m4/ltsugar.m4'
  libtoolize: copying file `m4/ltversion.m4'
  libtoolize: copying file `m4/lt~obsolete.m4'
  configure.ac:331: warning: PKG_PROG_PKG_CONFIG is m4_require'd but not m4_defun'd
  m4/gtk-doc.m4:7: GTK_DOC_CHECK is expanded from...
  configure.ac:331: the top level
  configure.ac:331: warning: PKG_PROG_PKG_CONFIG is m4_require'd but not m4_defun'd
  m4/gtk-doc.m4:7: GTK_DOC_CHECK is expanded from...
  configure.ac:331: the top level
  configure.ac:331: warning: PKG_PROG_PKG_CONFIG is m4_require'd but not m4_defun'd
  m4/gtk-doc.m4:7: GTK_DOC_CHECK is expanded from...
  configure.ac:331: the top level
  configure.ac:105: error: possibly undefined macro: AS_IF
        If this token and others are legitimate, please use m4_pattern_allow.
        See the Autoconf documentation.
  configure.ac:218: error: possibly undefined macro: AC_MSG_ERROR
  autoreconf: /opt/oblong/deps-64-10/bin/autoconf failed with exit status: 1
  </code></pre>
  <p>Thanks a lot for the help!</p>