diff --git a/include/cubescript/cubescript.hh b/include/cubescript/cubescript.hh
index 129706a1..b793a8bc 100644
--- a/include/cubescript/cubescript.hh
+++ b/include/cubescript/cubescript.hh
@@ -313,12 +313,6 @@ enum {
     CsLibAll    = 0b111
 };
 
-struct CsStackStateNode {
-    CsStackStateNode const *next;
-    CsIdent const *id;
-    int index;
-};
-
 using CsHookCb = ostd::Function<void(CsState &)>;
 using CsAllocCb = void *(*)(void *, void *, ostd::Size, ostd::Size);
 
@@ -411,6 +405,12 @@ struct OSTD_EXPORT CsState {
         alloc(v, sizeof(T), 0);
     }
 
+    template<typename T>
+    void destroy_array(T *v, ostd::Size len) noexcept {
+        v->~T();
+        alloc(v, len * sizeof(T), 0);
+    }
+
     void init_libs(int libs = CsLibAll);
 
     void clear_override(CsIdent &id);
@@ -558,8 +558,15 @@ private:
     CsStream *p_out, *p_err;
 };
 
+struct CsStackStateNode {
+    CsStackStateNode const *next;
+    CsIdent const *id;
+    int index;
+};
+
 struct CsStackState {
-    CsStackState(CsStackStateNode *nd = nullptr, bool gap = false);
+    CsStackState() = delete;
+    CsStackState(CsState &cs, CsStackStateNode *nd = nullptr, bool gap = false);
     CsStackState(CsStackState const &) = delete;
     CsStackState(CsStackState &&st);
     ~CsStackState();
@@ -571,6 +578,7 @@ struct CsStackState {
     bool gap() const;
 
 private:
+    CsState &p_state;
     CsStackStateNode *p_node;
     bool p_gap;
 };
@@ -597,7 +605,7 @@ struct CsErrorException {
     }
 
     CsErrorException(CsState &cs, ostd::ConstCharRange msg):
-        p_errmsg(), p_stack()
+        p_errmsg(), p_stack(cs)
     {
         p_errmsg = save_msg(cs, msg);
         p_stack = save_stack(cs);
@@ -605,7 +613,7 @@ struct CsErrorException {
 
     template<typename ...A>
     CsErrorException(CsState &cs, ostd::ConstCharRange msg, A &&...args):
-        p_errmsg(), p_stack()
+        p_errmsg(), p_stack(cs)
     {
         char fbuf[512];
         auto ret = ostd::format(
diff --git a/src/cs_vm.cc b/src/cs_vm.cc
index 5a28416c..4b2e9e80 100644
--- a/src/cs_vm.cc
+++ b/src/cs_vm.cc
@@ -35,18 +35,22 @@ static inline void cs_pop_alias(CsIdent *id) {
     }
 }
 
-CsStackState::CsStackState(CsStackStateNode *nd, bool gap):
-    p_node(nd), p_gap(gap)
+CsStackState::CsStackState(CsState &cs, CsStackStateNode *nd, bool gap):
+    p_state(cs), p_node(nd), p_gap(gap)
 {}
 CsStackState::CsStackState(CsStackState &&st):
-    p_node(st.p_node), p_gap(st.p_gap)
+    p_state(st.p_state), p_node(st.p_node), p_gap(st.p_gap)
 {
     st.p_node = nullptr;
     st.p_gap = false;
 }
 
 CsStackState::~CsStackState() {
-    delete[] p_node;
+    ostd::Size len = 0;
+    for (CsStackStateNode const *nd = p_node; nd; nd = nd->next) {
+        ++len;
+    }
+    p_state.destroy_array(p_node, len);
 }
 
 CsStackState &CsStackState::operator=(CsStackState &&st) {
@@ -68,17 +72,18 @@ bool CsStackState::gap() const {
 CsStackState cs_save_stack(CsState &cs) {
     CsIvar *dalias = static_cast<CsIvar *>(cs.p_state->identmap[DbgaliasIdx]);
     if (!dalias->get_value()) {
-        return CsStackState(nullptr, !!cs.p_callstack);
+        return CsStackState(cs, nullptr, !!cs.p_callstack);
     }
     int total = 0, depth = 0;
     for (CsIdentLink *l = cs.p_callstack; l; l = l->next) {
         total++;
     }
     if (!total) {
-        return CsStackState(nullptr, false);
+        return CsStackState(cs, nullptr, false);
     }
-    CsStackStateNode *st =
-        new CsStackStateNode[ostd::min(total, dalias->get_value())];
+    CsStackStateNode *st = cs.create_array<CsStackStateNode>(
+        ostd::min(total, dalias->get_value())
+    );
     CsStackStateNode *ret = st, *nd = st;
     ++st;
     for (CsIdentLink *l = cs.p_callstack; l; l = l->next) {
@@ -98,7 +103,7 @@ CsStackState cs_save_stack(CsState &cs) {
             nd->next = nullptr;
         }
     }
-    return CsStackState(ret, total > dalias->get_value());
+    return CsStackState(cs, ret, total > dalias->get_value());
 }
 
 CsStackState CsErrorException::save_stack(CsState &cs) {
diff --git a/src/cubescript.cc b/src/cubescript.cc
index ad20f9ea..ba8747a4 100644
--- a/src/cubescript.cc
+++ b/src/cubescript.cc
@@ -397,6 +397,7 @@ void *CsState::alloc(void *ptr, ostd::Size os, ostd::Size ns) {
     }
     if (!ns) {
         delete[] static_cast<unsigned char *>(ptr);
+        return nullptr;
     }
     return new unsigned char[ns];
 }