title: GNAT-GPS tutorial link error
body: <p>I am getting a link error when trying to build the sdc tutorial file.  I've installed the gnat gpl using the install script.  And the .o files exist in /usr/lib/x86_64-linux-gnu.
  How do I configure to get the linker to see?  I've tried adding to the path. </p>
  
  <p>here's the output:</p>
  
  <pre><code>gnatmake -d -P/home/steve/workspace/ada/tutorial/sdc.gpr -XBuild=DEBUG sdc.adb
  gnatbind -static -x /home/steve/workspace/ada/tutorial/obj/sdc.ali
  gnatlink /home/steve/workspace/ada/tutorial/obj/sdc.ali -g -o /home/steve/workspace/ada/tutorial/obj/sdc
  /usr/gnat/libexec/gcc/x86_64-pc-linux-gnu/4.7.4/ld: cannot find crt1.o: No such file or directory
  /usr/gnat/libexec/gcc/x86_64-pc-linux-gnu/4.7.4/ld: cannot find crti.o: No such file or directory
  /usr/gnat/libexec/gcc/x86_64-pc-linux-gnu/4.7.4/ld: cannot find -lc
  /usr/gnat/libexec/gcc/x86_64-pc-linux-gnu/4.7.4/ld: cannot find crtn.o: No such file or directory
  collect2: error: ld returned 1 exit status
  gnatlink: error when calling /usr/gnat/bin/gcc
  gnatmake: *** link failed.
  [2013-11-29 08:47:55] process exited with status 4 (elapsed time: 00.21s)
  </code></pre>