title: AC_CHECK_LIB(asan, _init) succeeds for some reason
body: <p>I am trying to figure out how <code>AC_CHECK_LIB([asan], [_init], ,[...])</code> succeeds despite the source for <code>asan</code> not having a symbol called <code>_init</code>.</p>
  <p>I verified the symbols by using <code>nm -D /path/to/libasan</code>. There is only one matching symbol called <code>__asan_init</code>.</p>
  <p>Shouldn't autoconf fail with error saying it is unable to locate symbol <code>init</code> in the said library?</p>
  <p>Regards</p>