commit 301f794f33d145b08fbf7f5247c8663d404fabb5
Author: Paul Eggert <eggert@cs.ucla.edu>
Date:   Fri Feb 26 08:58:45 2016 -0800

    Fix tzname redefinition in MS-Windows
    
    Problem reported by Ian Abbott in:
    http://mm.icann.org/pipermail/tz/2016-February/023289.html
    * localtime.c (tzname): Don’t define if HAVE_POSIX_DECLS,
    as causes the Microsoft compiler to complain that tzname
    is redeclared without dllimport.
    * localtime.c, private.h (altzone): Do define even if
    HAVE_POSIX_DECLS, since this is not a POSIX-specified variable.

diff --git a/localtime.c b/localtime.c
index e3bc763..276ce34 100644
--- a/localtime.c
+++ b/localtime.c
@@ -178,11 +178,6 @@ static struct state	gmtmem;
 static char		lcl_TZname[TZ_STRLEN_MAX + 1];
 static int		lcl_is_set;
 
-char *			tzname[2] = {
-	(char *) wildabbr,
-	(char *) wildabbr
-};
-
 /*
 ** Section 4.12.3 of X3.159-1989 requires that
 **	Except for the strftime function, these functions [asctime,
@@ -193,10 +188,16 @@ char *			tzname[2] = {
 
 static struct tm	tm;
 
-#ifdef USG_COMPAT
+#if !HAVE_POSIX_DECLS
+char *			tzname[2] = {
+	(char *) wildabbr,
+	(char *) wildabbr
+};
+# ifdef USG_COMPAT
 long			timezone;
 int			daylight;
-#endif /* defined USG_COMPAT */
+# endif
+#endif
 
 #ifdef ALTZONE
 long			altzone;
diff --git a/private.h b/private.h
index 6080e71..e23764d 100644
--- a/private.h
+++ b/private.h
@@ -386,8 +386,6 @@ time_t time(time_t *);
 void tzset(void);
 #endif
 
-#if !HAVE_POSIX_DECLS
-
 /*
 ** Some time.h implementations don't declare asctime_r.
 ** Others might define it as a macro.
@@ -395,24 +393,24 @@ void tzset(void);
 ** Similarly for timezone, daylight, and altzone.
 */
 
-#ifndef asctime_r
+#if !HAVE_POSIX_DECLS
+# ifndef asctime_r
 extern char *	asctime_r(struct tm const *restrict, char *restrict);
-#endif
-
-#ifdef USG_COMPAT
-# ifndef timezone
-extern long timezone;
 # endif
-# ifndef daylight
+# ifdef USG_COMPAT
+#  ifndef timezone
+extern long timezone;
+#  endif
+#  ifndef daylight
 extern int daylight;
+#  endif
 # endif
 #endif
+
 #if defined ALTZONE && !defined altzone
 extern long altzone;
 #endif
 
-#endif
-
 /*
 ** The STD_INSPIRED functions are similar, but most also need
 ** declarations if time_tz is defined.