diff --git a/ChangeLog b/ChangeLog
index 51a314e2c0..30b6c35dfe 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Fri May 13 02:15:18 2011  KOSAKI Motohiro  <kosaki.motohiro@gmail.com>
+
+	* io.c (select_internal): remove unused variable (interrupt_flag).
+
 Thu May 12 18:24:34 2011  Kouhei Sutou  <kou@clear-code.com>
 
 	* configure.in: limit to "T" type for prefix of external symbols
diff --git a/io.c b/io.c
index 4336eeda0e..86685afc58 100644
--- a/io.c
+++ b/io.c
@@ -7236,7 +7236,6 @@ select_internal(VALUE read, VALUE write, VALUE except, struct timeval *tp, rb_fd
     rb_io_t *fptr;
     long i;
     int max = 0, n;
-    int interrupt_flag = 0;
     int pending = 0;
     struct timeval timerec;
 
@@ -7306,49 +7305,47 @@ select_internal(VALUE read, VALUE write, VALUE except, struct timeval *tp, rb_fd
     rb_ary_push(res, wp?rb_ary_new():rb_ary_new2(0));
     rb_ary_push(res, ep?rb_ary_new():rb_ary_new2(0));
 
-    if (interrupt_flag == 0) {
-	if (rp) {
-	    list = RARRAY_PTR(res)[0];
-	    for (i=0; i< RARRAY_LEN(read); i++) {
-                VALUE obj = rb_ary_entry(read, i);
-                VALUE io = rb_io_get_io(obj);
-		GetOpenFile(io, fptr);
-		if (rb_fd_isset(fptr->fd, &fds[0]) ||
-		    rb_fd_isset(fptr->fd, &fds[3])) {
-		    rb_ary_push(list, obj);
-		}
+    if (rp) {
+	list = RARRAY_PTR(res)[0];
+	for (i=0; i< RARRAY_LEN(read); i++) {
+	    VALUE obj = rb_ary_entry(read, i);
+	    VALUE io = rb_io_get_io(obj);
+	    GetOpenFile(io, fptr);
+	    if (rb_fd_isset(fptr->fd, &fds[0]) ||
+		rb_fd_isset(fptr->fd, &fds[3])) {
+		rb_ary_push(list, obj);
 	    }
 	}
+    }
 
-	if (wp) {
-	    list = RARRAY_PTR(res)[1];
-	    for (i=0; i< RARRAY_LEN(write); i++) {
-                VALUE obj = rb_ary_entry(write, i);
-                VALUE io = rb_io_get_io(obj);
-                VALUE write_io = GetWriteIO(io);
+    if (wp) {
+	list = RARRAY_PTR(res)[1];
+	for (i=0; i< RARRAY_LEN(write); i++) {
+	    VALUE obj = rb_ary_entry(write, i);
+	    VALUE io = rb_io_get_io(obj);
+	    VALUE write_io = GetWriteIO(io);
+	    GetOpenFile(write_io, fptr);
+	    if (rb_fd_isset(fptr->fd, &fds[1])) {
+		rb_ary_push(list, obj);
+	    }
+	}
+    }
+
+    if (ep) {
+	list = RARRAY_PTR(res)[2];
+	for (i=0; i< RARRAY_LEN(except); i++) {
+	    VALUE obj = rb_ary_entry(except, i);
+	    VALUE io = rb_io_get_io(obj);
+	    VALUE write_io = GetWriteIO(io);
+	    GetOpenFile(io, fptr);
+	    if (rb_fd_isset(fptr->fd, &fds[2])) {
+		rb_ary_push(list, obj);
+	    }
+	    else if (io != write_io) {
 		GetOpenFile(write_io, fptr);
-		if (rb_fd_isset(fptr->fd, &fds[1])) {
-		    rb_ary_push(list, obj);
-		}
-	    }
-	}
-
-	if (ep) {
-	    list = RARRAY_PTR(res)[2];
-	    for (i=0; i< RARRAY_LEN(except); i++) {
-                VALUE obj = rb_ary_entry(except, i);
-                VALUE io = rb_io_get_io(obj);
-                VALUE write_io = GetWriteIO(io);
-		GetOpenFile(io, fptr);
 		if (rb_fd_isset(fptr->fd, &fds[2])) {
 		    rb_ary_push(list, obj);
 		}
-                else if (io != write_io) {
-                    GetOpenFile(write_io, fptr);
-                    if (rb_fd_isset(fptr->fd, &fds[2])) {
-                        rb_ary_push(list, obj);
-                    }
-                }
 	    }
 	}
     }