git: ae54b3ca7831 - stable/13 - sys/cdefs.h: Add comments to make #if/#else/#endif triple more obvious

The branch stable/13 has been updated by jrtc27:

URL: https://cgit.FreeBSD.org/src/commit/?id=ae54b3ca7831ca0bbfe40b9824e1b80163be94e3

commit ae54b3ca7831ca0bbfe40b9824e1b80163be94e3
Author:     Jessica Clarke <jrtc27@FreeBSD.org>
AuthorDate: 2024-11-20 20:09:28 +0000
Commit:     Jessica Clarke <jrtc27@FreeBSD.org>
CommitDate: 2025-12-15 17:56:35 +0000

    sys/cdefs.h: Add comments to make #if/#else/#endif triple more obvious
    
    This block has a lot of nesting, not helped by two adjacent nested
    blocks involving _POSIX_C_SOURCE, with only the inner one commented,
    looking like it's the end of the outer one. Comment the outer one as
    well so it's not quite so hard to figure out.
    
    MFC after:      1 week
    
    (cherry picked from commit 7a3af393d8ac2dfe72d24fe401344b60c4f87866)
---
 sys/sys/cdefs.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sys/sys/cdefs.h b/sys/sys/cdefs.h
index c549bfc3c2f3..fbd3c3144596 100644
--- a/sys/sys/cdefs.h
+++ b/sys/sys/cdefs.h
@@ -754,7 +754,7 @@
 #undef __ISO_C_VISIBLE
 #define __ISO_C_VISIBLE		2011
 #endif
-#else
+#else /* _POSIX_C_SOURCE */
 /*-
  * Deal with _ANSI_SOURCE:
  * If it is defined, and no other compilation environment is explicitly
@@ -792,7 +792,7 @@
 #define	__ISO_C_VISIBLE		2011
 #define	__EXT1_VISIBLE		1
 #endif
-#endif
+#endif /* _POSIX_C_SOURCE */
 
 /* User override __EXT1_VISIBLE */
 #if defined(__STDC_WANT_LIB_EXT1__)