From 23fee88f84873b0b8b41c8e5a9b229d533fb4022 Mon Sep 17 00:00:00 2001 From: Martin Uecker Date: Tue, 15 Aug 2023 14:58:32 +0200 Subject: c23: tag compatibility rules for struct and unions Implement redeclaration and compatibility rules for structures and unions in C23. gcc/c/: * c-decl.cc (previous_tag): New function. (parser_xref_tag): Find earlier definition. (get_parm_info): Turn off warning for C23. (start_struct): Allow redefinitons. (finish_struct): Diagnose conflicts. * c-tree.h (comptypes_same_p): Add prototype. * c-typeck.cc (comptypes_same_p): New function. (comptypes_internal): Activate comparison of tagged types. (convert_for_assignment): Ignore qualifiers. (digest_init): Add error. (initialized_elementwise_p): Allow compatible types. gcc/testsuite/: * gcc.dg/c23-enum-7.c: Remove warning. * gcc.dg/c23-tag-1.c: New test. * gcc.dg/c23-tag-2.c: New deactivated test. * gcc.dg/c23-tag-3.c: New test. * gcc.dg/c23-tag-4.c: New test. * gcc.dg/c23-tag-5.c: New deactivated test. * gcc.dg/c23-tag-6.c: New test. * gcc.dg/c23-tag-7.c: New test. * gcc.dg/c23-tag-8.c: New test. * gcc.dg/gnu23-tag-1.c: New test. * gcc.dg/gnu23-tag-2.c: New test. * gcc.dg/gnu23-tag-3.c: New test. * gcc.dg/gnu23-tag-4.c: New test. * gcc.dg/pr112488-2.c: Remove warning. --- gcc/c/c-tree.h | 1 + 1 file changed, 1 insertion(+) (limited to 'gcc/c/c-tree.h') diff --git a/gcc/c/c-tree.h b/gcc/c/c-tree.h index b325723..e53948f 100644 --- a/gcc/c/c-tree.h +++ b/gcc/c/c-tree.h @@ -757,6 +757,7 @@ extern tree c_objc_common_truthvalue_conversion (location_t, tree); extern tree require_complete_type (location_t, tree); extern bool same_translation_unit_p (const_tree, const_tree); extern int comptypes (tree, tree); +extern bool comptypes_same_p (tree, tree); extern int comptypes_check_different_types (tree, tree, bool *); extern int comptypes_check_enum_int (tree, tree, bool *); extern bool c_mark_addressable (tree, bool = false); -- cgit v1.1