diff --git a/testcase/userstack.c b/testcase/userstack.c
new file mode 100644
index 0000000..ad6d4ba
--- /dev/null
+++ b/testcase/userstack.c
@@ -0,0 +1,35 @@
+#include <stdio.h>
+#include <unistd.h>
+
+void customFunction1(int n);
+void customFunction2(int n);
+void customFunction3(int n);
+
+void customFunction1(int n) {
+    if(n <= 0) {
+        printf("End of recursion\n");
+        while (1) {
+            // sleep(1);
+        } // never return, keep stack
+        return;
+    } else {
+        printf("Calling customFunction2\n");
+        customFunction2(n-1);
+    }
+}
+
+void customFunction2(int n) {
+    printf("Calling customFunction3\n");
+    customFunction3(n);
+}
+
+void customFunction3(int n) {
+    printf("Calling customFunction1\n");
+    customFunction1(n);
+}
+
+int main() {
+    customFunction1(10);
+
+    return 0;
+}
\ No newline at end of file