diff --git a/test_libucontext.c b/test_libucontext.c
index 121cc3e..e5eac83 100644
--- a/test_libucontext.c
+++ b/test_libucontext.c
@@ -6,13 +6,32 @@
 #include <stdio.h>
 #include <ucontext.h>
 #include <stdint.h>
+#include <stdlib.h>
 #include <string.h>
 
 
 static ucontext_t ctx[3];
 
 
-static void f1 (void) {
+static void check_arg(int actual, int expected) {
+	if (actual == expected) return;
+	fprintf(stderr, "argument has wrong value.  got %d, expected %d.\n", actual, expected);
+	abort();
+}
+
+
+static void f1 (int a, int b, int c, int d, int e, int f, int g, int h, int i, int j) {
+	check_arg(a, 1);
+	check_arg(b, 2);
+	check_arg(c, 3);
+	check_arg(d, 4);
+	check_arg(e, 5);
+	check_arg(f, 6);
+	check_arg(g, 7);
+	check_arg(h, 8);
+	check_arg(i, 9);
+	check_arg(j, 10);
+
 	printf("start f1\n");
 	swapcontext(&ctx[1], &ctx[2]);
 	printf("finish f1\n");
@@ -40,7 +59,7 @@ int main (int argc, const char *argv[]) {
 	ctx[1].uc_stack.ss_sp = st1;
 	ctx[1].uc_stack.ss_size = sizeof st1;
 	ctx[1].uc_link = &ctx[0];
-	makecontext(&ctx[1], f1, 0);
+	makecontext(&ctx[1], f1, 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10);
 
 
 	getcontext(&ctx[2]);