Hi,
this patch drops types from decl context in free lang data. This is not possible
for field decls (because they are chained by TREE_CHAIN), for variably modified
types (becuase it is used in tree_is_indexable and other places) and for
virtual functions/tables (because it is used by devirt machinery to loop back
the type).
lto Bootstrapped/regtested x86_64-linux, OK?
* tree.c (free_lang_data_in_decl): Remove types from DECL_CONTEXT
when possible.
Index: tree.c
===================================================================
--- tree.c (revision 263586)
+++ tree.c (working copy)
@@ -5380,6 +5380,29 @@ free_lang_data_in_decl (tree decl)
nextp = &TREE_CHAIN (var);
}
}
+ /* We need to keep field decls associated with their trees. Otherwise tree
+ merging may merge some fileds and keep others disjoint wich in turn will
+ not do well with TREE_CHAIN pointers linking them.
+
+ Also do not drop containing types for virtual methods and tables because
+ these are needed by devirtualization. */
+ if (TREE_CODE (decl) != FIELD_DECL
+ && ((TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL)
+ || !DECL_VIRTUAL_P (decl)))
+ {
+ tree ctx = DECL_CONTEXT (decl);
+ /* Variably modified types are needed for tree_is_indexable to decide
+ whether the type needs to go to local or global section.
+ This code is semi-broken but for now it is easiest to keep contexts
+ as expected. */
+ if (ctx && TYPE_P (ctx)
+ && !variably_modified_type_p (ctx, NULL_TREE))
+ {
+ while (ctx && TYPE_P (ctx))
+ ctx = TYPE_CONTEXT (ctx);
+ DECL_CONTEXT (decl) = ctx;
+ }
+ }
}
