From 0a91bdaf177409a2a5e7895bce4f0e7091b4b3ca Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Wed, 7 Sep 2022 13:56:25 +0000 Subject: c: New C2x keywords C2x follows C++ in making alignas, alignof, bool, false, static_assert, thread_local and true keywords; implement this accordingly. This implementation makes them normal keywords in C2x mode just like any other keyword (C2x leaves open the possibility of implementation using predefined macros instead - thus, there aren't any testcases asserting that they aren't macros). As in C++ and previous versions of C, true and false are handled like signed 1 and 0 in #if (there was an intermediate state in some C2x drafts where they had different macro expansions that were unsigned in #if). Bootstrapped with no regressions for x86_64-pc-linux-gnu. As with the removal of unprototyped functions, this change has a high risk of breaking some old code and people doing GNU/Linux distribution builds may wish to see how much is broken in a build with a -std=gnu2x default. gcc/ * ginclude/stdalign.h [defined __STDC_VERSION__ && __STDC_VERSION__ > 201710L]: Disable all content. * ginclude/stdbool.h [defined __STDC_VERSION__ && __STDC_VERSION__ > 201710L] (bool, true, false): Do not define. gcc/c-family/ * c-common.cc (c_common_reswords): Use D_C2X instead of D_CXXONLY for alignas, alignof, bool, false, static_assert, thread_local and true. gcc/c/ * c-parser.cc (c_parser_static_assert_declaration_no_semi) (c_parser_alignas_specifier, c_parser_alignof_expression): Allow for C2x spellings of keywords. (c_parser_postfix_expression): Handle RID_TRUE and RID_FALSE. gcc/testsuite/ * gcc.dg/c11-keywords-1.c, gcc.dg/c2x-align-1.c, gcc.dg/c2x-align-6.c, gcc.dg/c2x-bool-2.c, gcc.dg/c2x-static-assert-3.c, gcc.dg/c2x-static-assert-4.c, gcc.dg/c2x-thread-local-1.c: New tests. * gcc.dg/c2x-bool-1.c: Update expectations. libcpp/ * include/cpplib.h (struct cpp_options): Add true_false. * expr.cc (eval_token): Check true_false not cplusplus to determine whether to handle true and false keywords. * init.cc (struct lang_flags): Add true_false. (lang_defaults): Update. (cpp_set_lang): Set true_false. --- libcpp/include/cpplib.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'libcpp/include') diff --git a/libcpp/include/cpplib.h b/libcpp/include/cpplib.h index c25bcf2..2db1e9c 100644 --- a/libcpp/include/cpplib.h +++ b/libcpp/include/cpplib.h @@ -526,6 +526,9 @@ struct cpp_options /* Nonzero for C++23 delimited escape sequences. */ unsigned char delimited_escape_seqs; + /* Nonzero for 'true' and 'false' in #if expressions. */ + unsigned char true_false; + /* Holds the name of the target (execution) character set. */ const char *narrow_charset; -- cgit v1.1