doc: Tweak wording about _Bool.

Reported by Alejandro Colomar <alx@kernel.org> in
<https://lists.gnu.org/archive/html/bug-gnulib/2025-11/msg00106.html>.

* doc/posix-headers/stdbool.texi: State that _Bool may be a keyword.

diff --git a/ChangeLog b/ChangeLog
index f86ce111d586337ed93e82056cba75a207458ab6..66c8c9fd962dbe1e00bd87206a649d56147311d0 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2025-11-11  Bruno Haible  <bruno@clisp.org>
+
+       doc: Tweak wording about _Bool.
+       Reported by Alejandro Colomar <alx@kernel.org> in
+       <https://lists.gnu.org/archive/html/bug-gnulib/2025-11/msg00106.html>.
+       * doc/posix-headers/stdbool.texi: State that _Bool may be a keyword.
+
 2025-11-10  Bruno Haible  <bruno@clisp.org>
 
        argp: Don't use an 'rpl_' function name prefix if not necessary.

diff --git a/doc/posix-headers/stdbool.texi b/doc/posix-headers/stdbool.texi
index dc4acc4f3f4b6dd5940de7e8b56a70513b498e80..0c841cfe5d0c7592dd725f276f57879592d78d71 100644 (file)
--- a/doc/posix-headers/stdbool.texi
+++ b/doc/posix-headers/stdbool.texi
@@ -34,8 +34,12 @@ Portability problems not fixed by Gnulib:
 the program is intended to be compiled by a C++ compiler.
 (With the advent of C23, @samp{_Bool} is obsolescent anyway.)
 @item
-You cannot assume that @code{_Bool} is a typedef; it might be a macro.
+You cannot assume that @code{_Bool} is a keyword or a typedef;
+@c In ISO C 99 § 6.4.1.(1) it is listed as a keyword.
+@c Older released of Mac OS X and FreeBSD define it as a typedef.
+it might be a macro.
 For example, C23 allows @code{_Bool} to be a macro.
+@c See ISO C 23 § 6.4.1.(3) footnote 63.
 @item
 Bit-fields of type @samp{bool} are not supported.  Portable code
 should use @samp{unsigned int foo : 1;} rather than @samp{bool foo : 1;}.