* systime.h (EMACS_TIME_CMP): Don't cast time_t values to long.

Fixes: debbugs:11712

2 files changed, 9 insertions, 7 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index fbe4f06da58..28e053be63f 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,8 @@
+2012-08-14  Ulrich Mueller  <ulm@gentoo.org>
+
+        * systime.h (EMACS_TIME_CMP): Don't cast time_t values to long
+        (Bug#11712).
+
 2012-08-13  Eli Zaretskii  <eliz@gnu.org>
 
         * w32menu.c: Include w32heap.h.
diff --git a/src/systime.h b/src/systime.h
index 9e7a1173a20..e6ebe4689df 100644
--- a/src/systime.h
+++ b/src/systime.h
@@ -147,15 +147,12 @@ extern int lisp_time_argument (Lisp_Object, time_t *, int *);
 #endif
 
 /* Compare times T1 and T2.  Value is 0 if T1 and T2 are the same.
-   Value is < 0 if T1 is less than T2.  Value is > 0 otherwise.  (Cast
-   to long is for those platforms where time_t is an unsigned
-   type, and where otherwise T1 will always be grater than T2.)  */
+   Value is < 0 if T1 is less than T2.  Value is > 0 otherwise.  */
 
 #define EMACS_TIME_CMP(T1, T2)                          \
-  ((long)EMACS_SECS (T1) - (long)EMACS_SECS (T2)        \
-   + (EMACS_SECS (T1) == EMACS_SECS (T2)                \
-      ? EMACS_USECS (T1) - EMACS_USECS (T2)             \
-      : 0))
+  (EMACS_SECS (T1) == EMACS_SECS (T2)                   \
+   ? EMACS_USECS (T1) - EMACS_USECS (T2)                \
+   : (EMACS_SECS (T1) < EMACS_SECS (T2) ? -1 : 1))
 
 /* Compare times T1 and T2 for equality, inequality etc.  */