title: automake 1.12 changes bison/yacc output names, backwards incompatible change?
body: <p>I have posted a repository at <a href="https://github.com/Habbie/autoyacc-problem" rel="nofollow">https://github.com/Habbie/autoyacc-problem</a> to demonstrate my issue.</p>
  
  <p>With automake 1.11 and below, using <code>AC_PROG_YACC</code> in configure.ac and <code>AM_YFLAGS=-d</code> in Makefile.am, parser.yy gets turned into parser.cc and parser.h. With automake 1.12, I get parser.cc and parser.hh. Because mybin.cc has <code>include "parser.h"</code>, this means 1.12 breaks my build.</p>
  
  <p>I have the feeling this is a backwards incompatible change, but I feel there should be a sane way to deal with this.</p>
  
  <p>To demonstrate:</p>
  
  <pre><code>git clone https://github.com/Habbie/autoyacc-problem.git
  cd autoyacc-problem/
  autoreconf -i
  ./configure
  make
  </code></pre>
  
  <p>Result with automake 1.11: mybin gets built. Result with automake 1.12:</p>
  
  <pre><code>mybin.cc:1:20: error: parser.h: No such file or directory
  </code></pre>
  
  <p>Help!</p>
  
  <p>Note: there is no actual C++ code in this example but for my real issue I do need g++.</p>