diff --git a/ChangeLog b/ChangeLog
index 43ecc955ba..0a2ca18700 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+Fri Dec 14 10:01:40 2007  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* configure.in (RUBY_CHECK_VARTYPE): check if a variable is defined
+	  and its type.
+
+	* configure.in (timezone, altzone): check for recent cygwin.
+
+	* missing/strftime.c (strftime): fix for timezone.  [ruby-dev:32536]
+
 Fri Dec 14 08:17:24 2007  Tanaka Akira  <akr@fsij.org>
 
 	* eval.c (rb_protect): restore root_jmpbuf even if proc exits by
diff --git a/configure.in b/configure.in
index eb94ff3c52..c07149b684 100644
--- a/configure.in
+++ b/configure.in
@@ -608,7 +608,7 @@ AC_CHECK_FUNCS(fmod killpg wait4 waitpid fork spawnv syscall chroot fsync getcwd
 	      dlopen sigprocmask sigaction _setjmp vsnprintf snprintf\
 	      setsid telldir seekdir fchmod cosh sinh tanh log2 round\
 	      setuid setgid daemon select_large_fdset setenv unsetenv\
-              mktime timegm clock_gettime)
+	      mktime timegm clock_gettime gettimeofday)
 AC_ARG_ENABLE(setreuid,
        [  --enable-setreuid       use setreuid()/setregid() according to need even if obsolete.],
        [use_setreuid=$enableval])
@@ -634,6 +634,30 @@ AC_CACHE_CHECK(for external int daylight, rb_cv_have_daylight,
 if test "$rb_cv_have_daylight" = yes; then
   AC_DEFINE(HAVE_DAYLIGHT)
 fi
+AC_DEFUN([RUBY_CHECK_VARTYPE], [dnl
+AC_CACHE_CHECK([for external $1], rb_cv_var_$1,
+  [rb_cv_var_$1=no
+  AC_TRY_COMPILE([#define _XOPEN_SOURCE 1
+    $2
+    void *t;],
+    [t = &(&$1)[0];],
+    [for t in $3; do
+      AC_TRY_COMPILE([#define _XOPEN_SOURCE 1
+        $2
+        extern $t $1;],
+        [void *t = &(&$1)[0];],
+        [rb_cv_var_$1=$t; break])
+    done])])
+if test "[$rb_cv_var_]$1" != no; then
+  AC_DEFINE([HAVE_VAR_]m4_toupper($1))
+  AC_DEFINE_UNQUOTED([TYPEOF_VAR_]m4_toupper($1), $rb_cv_var_$1)
+fi])
+RUBY_CHECK_VARTYPE(timezone, [#include <time.h>], [long int])
+RUBY_CHECK_VARTYPE(altzone, [#include <time.h>], [long int])
+if test "$rb_cv_var_timezone" = no; then
+  AC_CHECK_FUNCS(timezone)
+fi
+
 AC_CACHE_CHECK(for negative time_t for gmtime(3), rb_cv_negative_time_t,
   [AC_TRY_RUN([
 #include <time.h>
@@ -1213,7 +1237,7 @@ case "$target_os" in
   human*)
     AC_CHECK_LIB(signal, _harderr)
     AC_CHECK_LIB(hmem, hmemset)
-    AC_CHECK_FUNCS(select gettimeofday)
+    AC_CHECK_FUNCS(select)
     AC_CACHE_CHECK(whether PD libc _dtos18 fail to convert big number,
 		   rb_cv_missing__dtos18,
     [AC_TRY_RUN(
diff --git a/missing/strftime.c b/missing/strftime.c
index d9712f4f09..a4e780447e 100644
--- a/missing/strftime.c
+++ b/missing/strftime.c
@@ -115,17 +115,22 @@ extern char *strchr();
 
 #define range(low, item, hi)	max(low, min(item, hi))
 
-#if !defined(OS2) && !defined(MSDOS) && defined(HAVE_TZNAME)
-extern char *tzname[2];
-extern int daylight;
-#ifdef SOLARIS
-extern long timezone, altzone;
-#else
-#ifdef __hpux
-extern long timezone;
-#else
-extern int timezone, altzone;
+#ifdef __CYGWIN__
+#define DLL_IMPORT __declspec(dllimport)
 #endif
+#ifdef __WIN32__
+#define DLL_IMPORT __declspec(dllimport)
+#endif
+#if !defined(OS2) && !defined(MSDOS) && defined(HAVE_TZNAME)
+extern DLL_IMPORT char *tzname[2];
+#ifdef HAVE_DAYLIGHT
+extern DLL_IMPORT int daylight;
+#endif
+#ifdef HAVE_VAR_TIMEZONE
+extern DLL_IMPORT TYPEOF_VAR_TIMEZONE timezone;
+#endif
+#ifdef HAVE_VAR_ALTZONE
+extern DLL_IMPORT TYPEOF_VAR_ALTZONE altzone;
 #endif
 #endif
 
@@ -189,16 +194,8 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
 #endif /* POSIX_SEMANTICS */
 #ifndef HAVE_TM_ZONE
 #ifndef HAVE_TM_NAME
-#ifndef HAVE_TZNAME
-	extern char *timezone();
 	struct timeval tv;
 	struct timezone zone;
-#else
-#ifdef __hpux
-	struct timeval tv;
-	struct timezone zone;
-#endif
-#endif /* HAVE_TZNAME */
 #endif /* HAVE_TM_NAME */
 #endif /* HAVE_TM_ZONE */
 
@@ -422,21 +419,18 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
 			 */
 			off = timeptr->tm_gmtoff / 60;
 #else /* !HAVE_TM_ZONE */
-#if HAVE_TZNAME
-			/*
-			 * Systems with tzname[] probably have timezone as
-			 * secs west of GMT.  Convert to mins east of GMT.
-			 */
-#ifdef __hpux
+#ifdef HAVE_GETTIMEOFDAY
 			gettimeofday(&tv, &zone);
 			off = -zone.tz_minuteswest;
 #else
+#if HAVE_VAR_TIMEZONE
+#if HAVE_VAR_ALTZONE
 			off = -(daylight ? timezone : altzone) / 60;
+#else
+			off = -timezone / 60;
+#endif
+#endif
 #endif
-#else /* !HAVE_TZNAME */
-			gettimeofday(&tv, &zone);
-			off = -zone.tz_minuteswest;
-#endif /* !HAVE_TZNAME */
 #endif /* !HAVE_TM_ZONE */
 #endif /* !HAVE_TM_NAME */
 			if (off < 0) {
@@ -460,13 +454,15 @@ strftime(char *s, size_t maxsize, const char *format, const struct tm *timeptr)
 #ifdef HAVE_TM_NAME
 			strcpy(tbuf, timeptr->tm_name);
 #else
+#ifdef HAVE_TIMEZONE
 			gettimeofday(& tv, & zone);
-#ifdef __CYGWIN__
+#ifdef TIMEZONE_VOID
 			strcpy(tbuf, timezone());
 #else
 			strcpy(tbuf, timezone(zone.tz_minuteswest,
 						timeptr->tm_isdst > 0));
-#endif
+#endif /* TIMEZONE_VOID */
+#endif /* HAVE_TIMEZONE */
 #endif /* HAVE_TM_NAME */
 #endif /* HAVE_TM_ZONE */
 #endif /* HAVE_TZNAME */
@@ -645,7 +641,7 @@ iso8601wknum(const struct tm *timeptr)
 	 * main body of the standard. Thus it requires week 53.
 	 */
 
-	int weeknum, jan1day, diff;
+	int weeknum, jan1day;
 
 	/* get week number, Monday as first day of the week */
 	weeknum = weeknumber(timeptr, 1);