>From 35589c5a953da353f9cb56984a161c7c91019e4a Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Thu, 31 Dec 2020 19:14:49 -0800
Subject: [PATCH] doc: mention year-0 bugs in Solaris etc.

* doc/posix-functions/gmtime.texi, doc/posix-functions/gmtime_r.texi:
* doc/posix-functions/localtime.texi:
* doc/posix-functions/localtime_r.texi:
* doc/posix-functions/mktime.texi:
Mention year-0 bugs in localtime etc.
---
 ChangeLog                            | 9 +++++++++
 doc/posix-functions/gmtime.texi      | 4 ++++
 doc/posix-functions/gmtime_r.texi    | 4 ++++
 doc/posix-functions/localtime.texi   | 4 ++++
 doc/posix-functions/localtime_r.texi | 4 ++++
 doc/posix-functions/mktime.texi      | 4 ++++
 6 files changed, 29 insertions(+)

diff --git a/ChangeLog b/ChangeLog
index 9cb45d0d7..e8b956828 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2020-12-31  Paul Eggert  <eggert@cs.ucla.edu>
+
+	doc: mention year-0 bugs in Solaris etc.
+	* doc/posix-functions/gmtime.texi, doc/posix-functions/gmtime_r.texi:
+	* doc/posix-functions/localtime.texi:
+	* doc/posix-functions/localtime_r.texi:
+	* doc/posix-functions/mktime.texi:
+	Mention year-0 bugs in localtime etc.
+
 2020-12-31  Bruno Haible  <bruno@clisp.org>
 
 	ptsname_r: Fix test failure on Solaris.
diff --git a/doc/posix-functions/gmtime.texi b/doc/posix-functions/gmtime.texi
index 64d4f7df7..7590fe910 100644
--- a/doc/posix-functions/gmtime.texi
+++ b/doc/posix-functions/gmtime.texi
@@ -12,4 +12,8 @@ Portability problems fixed by Gnulib:
 
 Portability problems not fixed by Gnulib:
 @itemize
+@item
+On some platforms, this function yields incorrect values for
+timestamps before the year 1:
+MacOS X 10.5, Solaris 11.3.
 @end itemize
diff --git a/doc/posix-functions/gmtime_r.texi b/doc/posix-functions/gmtime_r.texi
index 7e280186e..af815af83 100644
--- a/doc/posix-functions/gmtime_r.texi
+++ b/doc/posix-functions/gmtime_r.texi
@@ -19,4 +19,8 @@ HP-UX 11.
 
 Portability problems not fixed by Gnulib:
 @itemize
+@item
+On some platforms, this function yields incorrect values for
+timestamps before the year 1:
+MacOS X 10.5, Solaris 11.3.
 @end itemize
diff --git a/doc/posix-functions/localtime.texi b/doc/posix-functions/localtime.texi
index 040102b9b..0cad93c1b 100644
--- a/doc/posix-functions/localtime.texi
+++ b/doc/posix-functions/localtime.texi
@@ -25,6 +25,10 @@ On some platforms, this function returns nonsense values for
 unsupported arguments (like @math{2^56}), rather than failing:
 FreeBSD 10.
 @item
+On some platforms, this function yields incorrect values for
+timestamps before the year 1:
+MacOS X 10.5, Solaris 11.3.
+@item
 Native Windows platforms (mingw, MSVC) support only a subset of time
 zones supported by GNU or specified by POSIX@.  @xref{tzset}.
 @end itemize
diff --git a/doc/posix-functions/localtime_r.texi b/doc/posix-functions/localtime_r.texi
index 420bc2ee1..fd484f8d4 100644
--- a/doc/posix-functions/localtime_r.texi
+++ b/doc/posix-functions/localtime_r.texi
@@ -28,4 +28,8 @@ You can use the @code{time_rz} module to work around the problem.
 On some platforms, this function returns nonsense values for
 unsupported arguments (like @math{2^56}), rather than failing:
 FreeBSD 10.
+@item
+On some platforms, this function yields incorrect values for
+timestamps before the year 1:
+MacOS X 10.5, Solaris 11.3.
 @end itemize
diff --git a/doc/posix-functions/mktime.texi b/doc/posix-functions/mktime.texi
index bf4be1836..a7713b5a0 100644
--- a/doc/posix-functions/mktime.texi
+++ b/doc/posix-functions/mktime.texi
@@ -20,6 +20,10 @@ when the environment variable @code{TZ} has been set by Cygwin.
 Portability problems not fixed by Gnulib:
 @itemize
 @item
+On some platforms, this function yields incorrect values for
+timestamps before the year 1:
+MacOS X 10.5, Solaris 11.3.
+@item
 Native Windows platforms (mingw, MSVC) support only a subset of time
 zones supported by GNU or specified by POSIX@.  @xref{tzset}.
 @end itemize
-- 
2.27.0