From 6371df556ca7d5fa52947cb5fbe414bbfb5a0e4d Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Mon, 20 Feb 2012 07:54:04 -0700
Subject: [PATCH] yet anther attempt to work around the Mac 10.7 localtime()
 bug

I now think the problem is likely to be realted to values
that do not fit into a signed 32-bit integer. Check for
the OS version and reject such integers.
---
 src/racket/sconfig.h |  5 -----
 src/racket/src/fun.c | 40 +++++++++++++++++++++++++++++++++++++---
 2 files changed, 37 insertions(+), 8 deletions(-)

diff --git a/src/racket/sconfig.h b/src/racket/sconfig.h
index b8b21bfb5b..b84942b028 100644
--- a/src/racket/sconfig.h
+++ b/src/racket/sconfig.h
@@ -768,11 +768,6 @@
 #endif
 # define MZ_JIT_USE_MPROTECT
 
-#if defined(__x86_64__)
-/* work around a bug in localtime() in 10.6.8 */
-# define MIN_VALID_DATE_SECONDS -67768040609715600
-#endif
-
 # define FLAGS_ALREADY_SET
 
 #endif
diff --git a/src/racket/src/fun.c b/src/racket/src/fun.c
index 77877f45f2..8c83515bf3 100644
--- a/src/racket/src/fun.c
+++ b/src/racket/src/fun.c
@@ -8320,10 +8320,44 @@ static int month_offsets[12] = { 0, 31, 59, 90,
                                 243, 273, 304, 334 };
 #endif
 
-#ifdef MIN_VALID_DATE_SECONDS
-# define VALID_TIME_RANGE(x) ((x) >= MIN_VALID_DATE_SECONDS)
+#if (defined(OS_X) || defined(XONX)) && defined(__x86_64__)
+/* work around a bug in localtime() in 10.6.8 */
+# include <sys/param.h>
+# include <sys/sysctl.h>
+static int VALID_TIME_RANGE(UNBUNDLE_TIME_TYPE lnow)
+{
+  /* Fits in 32 bits? */
+  int ilnow = (int)lnow;
+  if (lnow == (UNBUNDLE_TIME_TYPE)ilnow)
+    return 1;
+
+  /* 10.7 or later? */
+  {
+    int a[2];
+    size_t len;
+    char *vers;
+
+    a[0] = CTL_KERN;
+    a[1] = KERN_OSRELEASE;
+    sysctl(a, 2, NULL, &len, NULL, 0);
+    vers = (char *)scheme_malloc_atomic(len * sizeof(char));
+    sysctl(a, 2, vers, &len, NULL, 0);
+
+    if ((vers[0] == '1') && (vers[1] == '0') && (vers[2] == '.')) {
+      /* localtime() in 10.7.x (= 10.x at the kernel layer) doesn't seem
+         to work right with negative numbers that don't fit into 32 bits */
+      return 0;
+    }
+  }
+
+  return 1;
+}
 #else
-# define VALID_TIME_RANGE(x) 1
+# ifdef MIN_VALID_DATE_SECONDS
+#  define VALID_TIME_RANGE(x) ((x) >= MIN_VALID_DATE_SECONDS)
+# else
+#  define VALID_TIME_RANGE(x) 1
+# endif
 #endif
 
 static Scheme_Object *seconds_to_date(int argc, Scheme_Object **argv)