gimple.c (gimple_types_compatible_p): Check type qualifications before merging…

gimple.c (gimple_types_compatible_p): Check type qualifications before merging pointer to complete and pointer to...

2010-05-22  Richard Guenther  <rguenther@suse.de>

	* gimple.c (gimple_types_compatible_p): Check type qualifications
	before merging pointer to complete and pointer to incomplete type.
	* lto-symtab.c (lto_symtab_resolve_symbols): For commons make sure
	we use our own resolution algorithm.  The gold linker plugin
	doesn't do the job we want it to do here.

	lto/
	* lto.c (read_cgraph_and_symbols): Do not collect.

From-SVN: r159696

gcc/ChangeLog

+2010-05-22  Richard Guenther  <rguenther@suse.de>
+
+	* gimple.c (gimple_types_compatible_p): Check type qualifications
+	before merging pointer to complete and pointer to incomplete type.
+	* lto-symtab.c (lto_symtab_resolve_symbols): For commons make sure
+	we use our own resolution algorithm.  The gold linker plugin
+	doesn't do the job we want it to do here.
+
 2010-05-22  Anatoly Sokolov  <aesok@post.ru>
 
 	* config/sparc/sparc.h (GO_IF_MODE_DEPENDENT_ADDRESS): Remove.

gcc/gimple.c

@@ -3481,11 +3481,20 @@ gimple_types_compatible_p (tree t1, tree t2)
 	    && RECORD_OR_UNION_TYPE_P (TREE_TYPE (t1))
 	    && (!COMPLETE_TYPE_P (TREE_TYPE (t1))
 		|| !COMPLETE_TYPE_P (TREE_TYPE (t2)))
+	    && TYPE_QUALS (TREE_TYPE (t1)) == TYPE_QUALS (TREE_TYPE (t2))
 	    && compare_type_names_p (TYPE_MAIN_VARIANT (TREE_TYPE (t1)),
 				     TYPE_MAIN_VARIANT (TREE_TYPE (t2)), true))
 	  {
 	    /* Replace the pointed-to incomplete type with the
-	       complete one.  */
+	       complete one.
+	       ???  This simple name-based merging causes at least some
+	       of the ICEs in canonicalizing FIELD_DECLs during stmt
+	       read.  For example in GCC we have two different struct deps
+	       and we mismatch the use in struct cpp_reader in sched-int.h
+	       vs. mkdeps.c.  Of course the whole exercise is for TBAA
+	       with structs which contain pointers to incomplete types
+	       in one unit and to complete ones in another.  So we
+	       probably should merge these types only with more context.  */
 	    if (COMPLETE_TYPE_P (TREE_TYPE (t2)))
 	      TREE_TYPE (t1) = TREE_TYPE (t2);
 	    else

gcc/lto-symtab.c

@@ -463,7 +463,13 @@ lto_symtab_resolve_symbols (void **slot)
       if (TREE_CODE (e->decl) == FUNCTION_DECL)
 	e->node = cgraph_get_node (e->decl);
       else if (TREE_CODE (e->decl) == VAR_DECL)
-	e->vnode = varpool_get_node (e->decl);
+	{
+	  e->vnode = varpool_get_node (e->decl);
+	  /* The LTO plugin for gold doesn't handle common symbols
+	     properly.  Let us choose manually.  */
+	  if (DECL_COMMON (e->decl))
+	    e->resolution = LDPR_UNKNOWN;
+	}
     }
 
   e = (lto_symtab_entry_t) *slot;

gcc/lto/ChangeLog

+2010-05-22  Richard Guenther  <rguenther@suse.de>
+
+	* lto.c (read_cgraph_and_symbols): Do not collect.
+
 2010-05-20  Jan Hubicka  <jh@suse.cz>
 
 	* lto.c (promote_var, promote_fn): New functions.

gcc/lto/lto.c

@@ -1633,7 +1633,8 @@ read_cgraph_and_symbols (unsigned nfiles, const char **fnames)
 
       lto_obj_file_close (current_lto_file);
       current_lto_file = NULL;
-      ggc_collect ();
+      /* ???  We'd want but can't ggc_collect () here as the type merging
+         code in gimple.c uses hashtables that are not ggc aware.  */
     }
 
   if (resolution_file_name)