* win32/win32.c (subtruct): check tv_sec. reported by ko1.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@19484 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 3 insertions, 0 deletions

diff --git a/win32/win32.c b/win32/win32.c
index 5774d0c503..bcf4bd77ea 100644
--- a/win32/win32.c
+++ b/win32/win32.c
@@ -2157,6 +2157,9 @@ do_select(int nfds, fd_set *rd, fd_set *wr, fd_set *ex,
 static inline int
 subtract(struct timeval *rest, const struct timeval *wait)
 {
+    if (rest->tv_sec < wait->tv_sec) {
+	return 0;
+    }
     while (rest->tv_usec < wait->tv_usec) {
 	if (rest->tv_sec <= wait->tv_sec) {
 	    return 0;