[chkp] Do not stream bodies of instrumentation thunks

[Jan Hubicka]

Hi,
instrumentation thunks are de-facto transparent aliases and thus their bodies
should not be streamed (longer term plan is to reorganize them to aliases).
This avoids an ICE when mixing instrumented and non-instrumented files in LTO.

Bootstrapped/regtested x86_64-linux, plan to commit it if there are no complains.

Honza

	* lto-streamer-out.c (lto_output): Do not stream instrumentation
	thunks.
Index: lto-streamer-out.c
===================================================================
--- lto-streamer-out.c	(revision 232466)
+++ lto-streamer-out.c	(working copy)
@@ -2320,7 +2320,8 @@ lto_output (void)
       if (cgraph_node *node = dyn_cast <cgraph_node *> (snode))
 	{
 	  if (lto_symtab_encoder_encode_body_p (encoder, node)
-	      && !node->alias)
+	      && !node->alias
+	      && (!node->thunk.thunk_p || !node->instrumented_version))
 	    {
 	      if (flag_checking)
 		{