[PATCH] ginclude: Add comments about <stdalign.h> and <stdbool.h> in C++

[Jonathan Wakely]

The stdalign.h macros were removed from C++26 but this patch just tweaks
the comment, without actually removing them. Doing so would be a
breaking change, although probably not in practice because it seems very
unlikely any C++ code is checking those macros.

The macros were also removed from C23, so if we remove them from
stdalign.h for C then we can decide to do the same for C++ at that time.

gcc/ChangeLog:

	* ginclude/stdalign.h: Note that the macros were removed from
	C++ in C++26.
	* ginclude/stdbool.h: Note that the macro is deprecated since
	C++23.
---

Tested x86_64-linux.

OK for trunk?

 gcc/ginclude/stdalign.h | 2 +-
 gcc/ginclude/stdbool.h  | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/gcc/ginclude/stdalign.h b/gcc/ginclude/stdalign.h
index a68cb28059ce..94ecbf14a417 100644
--- a/gcc/ginclude/stdalign.h
+++ b/gcc/ginclude/stdalign.h
@@ -33,7 +33,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #define alignof _Alignof
 #endif
 
-/* These are defined for C++, but deprecated in C++23.  */
+/* These are defined for C++, but deprecated in C++23 and gone in C++26.  */
 #define __alignas_is_defined 1
 #define __alignof_is_defined 1
 
diff --git a/gcc/ginclude/stdbool.h b/gcc/ginclude/stdbool.h
index 9070a1876233..6f72714f6d62 100644
--- a/gcc/ginclude/stdbool.h
+++ b/gcc/ginclude/stdbool.h
@@ -46,6 +46,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #endif /* __cplusplus */
 
 /* Signal that all the definitions are present.  */
+/* This is defined for C++, but deprecated in C++23.  */
 #define __bool_true_false_are_defined	1
 
 #endif	/* stdbool.h */
-- 
2.55.0