* c-family/c-common.c (handle_alias_ifunc_attribute): Do not set
DECL_EXTERNAL for weakref variables.
* c-family/c-pragma.c (handle_pragma_weak): Make sure aliases
are not declared as external.
* cgraph.c (cgraph_create_function_alias): Set weakref flag.
* cgraph.h (symtab_node_base): Add weakref flag.
* cgraphunit.c (cgraph_reset_node): Clear weakref flag.
(handle_alias_pairs): Set weakref flag, do not set DECL_EXTERNAL.
(output_weakrefs): Use weakref flag.
* fold-const.c (simple_operand_p): Handle WEAK.
* gimple-fold.c (can_refer_decl_in_current_unit_p): Drop weakref.
* ipa.c (varpool_externally_visible_p): Drop weakref.
(function_and_variable_visibility): Update comment; fix weakref
sanity checks; do not clear DECL_WEAK on them.
* lto-cgraph.c (lto_output_node): update.
(lto_output_varpool_node): Update.
(input_overwrite_node): Update.
(input_node): Update.
(input_varpool_node): Update.
* lto-symtab.c (lto_symtab_symbol_p): Do not special case weakrefs.
(lto_symtab_merge_symbols): Add sanity check.
(lto_symtab_prevailing_decl): Do not special case weakrefs.
* passes.c (rest_of_decl_compilation): Set static flag, too.
* symtab.c (dump_symtab_base): Dump weakref.
(verify_symtab_base): Sanity check weakrefs.
(symtab_make_decl_local): Remove duplicated code.
(symtab_alias_ultimate_target): Simplify.
* varpool.c (varpool_create_variable_alias): Set weakref flag.
* lto-partition.c (get_symbol_class): Simplify weakref handling.
(add_symbol_to_partition_1): Likewise.
(contained_in_symbol): Likewise.
(lto_balanced_map): Likewise.
(rename_statics): Drop weakref.
From-SVN: r199971
