From dd6f973d5c4be92f8eaf124cb841e3b02076adef Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Sat, 12 Jul 2014 08:10:22 +0100
Subject: [PATCH] ffi/unsafe/com: convert to `date*`, document limitations

Merge to v6.1 along with 7d65ee6127.
(cherry picked from commit 689f449c8de2dd911ba149e59ae784e5572b7302)
---
 .../scribblings/foreign/com-auto.scrbl        |  4 +++-
 racket/collects/ffi/unsafe/com.rkt            | 22 ++++++++++---------
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/pkgs/racket-pkgs/racket-doc/scribblings/foreign/com-auto.scrbl b/pkgs/racket-pkgs/racket-doc/scribblings/foreign/com-auto.scrbl
index 6d38f165e0..06685ea420 100644
--- a/pkgs/racket-pkgs/racket-doc/scribblings/foreign/com-auto.scrbl
+++ b/pkgs/racket-pkgs/racket-doc/scribblings/foreign/com-auto.scrbl
@@ -449,7 +449,9 @@ used to represent various atomic types:
 
  @item{@racket['string] --- a string}
 
- @item{@racket['date] --- a @racket[date] or @racket[date*]}
+ @item{@racket['date] --- a @racket[date] or @racket[date*]; when converting to
+       a @racket[date*], the timezone is reported as @racket["UTC"] and the
+       @racket[year-day] field is @racket[0]}
 
  @item{@racket['com-object] --- a @tech{COM object} as in @racket[com-object?]}
 
diff --git a/racket/collects/ffi/unsafe/com.rkt b/racket/collects/ffi/unsafe/com.rkt
index 7c349181a7..c728be74f4 100644
--- a/racket/collects/ffi/unsafe/com.rkt
+++ b/racket/collects/ffi/unsafe/com.rkt
@@ -1447,16 +1447,18 @@
                 (define s (make-SYSTEMTIME 0 0 0 0 0 0 0 0))
                 (unless (not (zero? (VariantTimeToSystemTime d s)))
                   (error 'date "error converting date from COM date"))
-                (date (SYSTEMTIME-wSecond s)
-                      (SYSTEMTIME-wMinute s)
-                      (SYSTEMTIME-wHour s)
-                      (SYSTEMTIME-wDay s)
-                      (SYSTEMTIME-wMonth s)
-                      (SYSTEMTIME-wYear s)
-                      (SYSTEMTIME-wDayOfWeek s)
-                      0
-                      #f
-                      0))))
+                (date* (SYSTEMTIME-wSecond s)
+                       (SYSTEMTIME-wMinute s)
+                       (SYSTEMTIME-wHour s)
+                       (SYSTEMTIME-wDay s)
+                       (SYSTEMTIME-wMonth s)
+                       (SYSTEMTIME-wYear s)
+                       (SYSTEMTIME-wDayOfWeek s)
+                       0
+                       #f
+                       0
+                       (* 1000 (SYSTEMTIME-wMilliseconds s))
+                       "UTC"))))
 
 (define _currency
   (make-ctype _CY