title: Symbol lookup error undefined symbol, but all symbols seem to be present
body: <p>An executable seemingly can't resolve a symbol in a linked library. The relevant output of LD_DEBUG=libs shows that the correct library is loaded:
  <code>
  6557:     /usr/lib/libcharon.so.0: error: symbol lookup error: undefined symbol: auth_class_names (fatal)
                  /usr/libexec/ipsec/charon: symbol lookup error: /usr/lib/libcharon.so.0: undefined symbol: auth_class_names
  </code></p>
  
  <p>nm -D shows that the symbol auth_class_names is defined:</p>
  
  <p><code>
   nm -D /usr/lib/libcharon.so.0|grep auth_class_names
           U auth_class_names
  </code></p>
  
  <p>All clues and ideas welcome</p>
  
  <p>EDIT: Outputs of ldd added:</p>
  
  <pre><code>/usr/lib# ldd /usr/lib/libstrongswan.so
      libpthread.so.0 =&gt; /lib/arm-linux-gnueabi/libpthread.so.0 (0xb6ecd000)
      libdl.so.2 =&gt; /lib/arm-linux-gnueabi/libdl.so.2 (0xb6ec2000)
      librt.so.1 =&gt; /lib/arm-linux-gnueabi/librt.so.1 (0xb6eb3000)
      libc.so.6 =&gt; /lib/arm-linux-gnueabi/libc.so.6 (0xb6d78000)
      /lib/ld-linux.so.3 (0xb6f25000)
  /usr/lib# ldd /usr/lib/libcharon.so
      libm.so.6 =&gt; /lib/arm-linux-gnueabi/libm.so.6 (0xb6ea6000)
      libpthread.so.0 =&gt; /lib/arm-linux-gnueabi/libpthread.so.0 (0xb6e86000)
      libdl.so.2 =&gt; /lib/arm-linux-gnueabi/libdl.so.2 (0xb6e7b000)
      libcap.so.2 =&gt; /lib/arm-linux-gnueabi/libcap.so.2 (0xb6e70000)
      libc.so.6 =&gt; /lib/arm-linux-gnueabi/libc.so.6 (0xb6d35000)
      /lib/ld-linux.so.3 (0xb6fa6000)
      libattr.so.1 =&gt; /lib/arm-linux-gnueabi/libattr.so.1 (0xb6d27000)
  
  # nm -D /usr/lib/libstrongswan.so|grep auth_class
  00036a50 D auth_class_names
  </code></pre>