diff --git a/include/cubescript/cubescript.hh b/include/cubescript/cubescript.hh
index 7fbcc62..1e0f5e8 100644
--- a/include/cubescript/cubescript.hh
+++ b/include/cubescript/cubescript.hh
@@ -42,6 +42,7 @@ enum {
 
 struct cs_bcode;
 struct cs_value;
+struct cs_state;
 struct cs_shared_state;
 
 struct OSTD_EXPORT cs_bcode_ref {
@@ -88,8 +89,8 @@ private:
     /* for internal use only */
     cs_strref(char const *p, cs_shared_state &cs);
 
-    char const *p_str;
     cs_shared_state *p_state;
+    char const *p_str;
 };
 
 enum class cs_value_type {
@@ -97,14 +98,17 @@ enum class cs_value_type {
 };
 
 struct OSTD_EXPORT cs_value {
-    cs_value();
+    cs_value() = delete;
     ~cs_value();
 
+    cs_value(cs_state &);
+    cs_value(cs_shared_state &);
+
     cs_value(cs_value const &);
     cs_value(cs_value &&);
 
-    cs_value &operator=(cs_value const &v);
-    cs_value &operator=(cs_value &&v);
+    cs_value &operator=(cs_value const &);
+    cs_value &operator=(cs_value &&);
 
     cs_value_type get_type() const;
 
@@ -135,7 +139,22 @@ struct OSTD_EXPORT cs_value {
     bool code_is_empty() const;
 
 private:
-    std::aligned_union_t<1, cs_int, cs_float, void *> p_stor;
+    template<typename T>
+    struct stor_t {
+        cs_shared_state *state;
+        T val;
+    };
+
+    cs_shared_state *state() const {
+        return reinterpret_cast<stor_t<void *> const *>(&p_stor)->state;
+    }
+
+    std::aligned_union_t<1,
+        stor_t<cs_int>,
+        stor_t<cs_float>,
+        stor_t<void *>,
+        cs_strref
+    > p_stor;
     size_t p_len;
     cs_value_type p_type;
 };
@@ -143,6 +162,8 @@ private:
 struct cs_ident_stack {
     cs_value val_s;
     cs_ident_stack *next;
+
+    cs_ident_stack(cs_state &cs): val_s{cs}, next{nullptr} {}
 };
 
 struct cs_error;
@@ -308,11 +329,11 @@ struct OSTD_EXPORT cs_alias: cs_ident {
     void get_cstr(cs_value &v) const;
     void get_cval(cs_value &v) const;
 private:
-    cs_alias(ostd::string_range n, cs_string a, int flags);
-    cs_alias(ostd::string_range n, cs_int a, int flags);
-    cs_alias(ostd::string_range n, cs_float a, int flags);
-    cs_alias(ostd::string_range n, int flags);
-    cs_alias(ostd::string_range n, cs_value v, int flags);
+    cs_alias(cs_state &cs, ostd::string_range n, cs_string a, int flags);
+    cs_alias(cs_state &cs, ostd::string_range n, cs_int a, int flags);
+    cs_alias(cs_state &cs, ostd::string_range n, cs_float a, int flags);
+    cs_alias(cs_state &cs, ostd::string_range n, int flags);
+    cs_alias(cs_state &cs, ostd::string_range n, cs_value v, int flags);
 
     cs_bcode *p_acode;
     cs_ident_stack *p_astack;
@@ -362,6 +383,7 @@ static inline void *cs_default_alloc(void *, void *p, size_t, size_t ns) {
 struct OSTD_EXPORT cs_state {
     friend struct cs_error;
     friend struct cs_strman;
+    friend struct cs_value;
     friend struct cs_gen_state;
 
     cs_shared_state *p_state;
@@ -603,7 +625,7 @@ private:
 };
 
 struct OSTD_EXPORT cs_stacked_value: cs_value {
-    cs_stacked_value(cs_ident *id = nullptr);
+    cs_stacked_value(cs_state &cs, cs_ident *id = nullptr);
     ~cs_stacked_value();
 
     cs_stacked_value(cs_stacked_value const &) = delete;
diff --git a/src/cs_val.cc b/src/cs_val.cc
index 19a1e6b..bc6dd71 100644
--- a/src/cs_val.cc
+++ b/src/cs_val.cc
@@ -4,10 +4,16 @@
 
 namespace cscript {
 
+template<typename T>
+struct stor_priv_t {
+    cs_shared_state *state;
+    T val;
+};
+
 template<typename T, typename U>
 static inline T &csv_get(U &stor) {
     /* ugly, but internal and unlikely to cause bugs */
-    return const_cast<T &>(reinterpret_cast<T const &>(stor));
+    return const_cast<T &>(reinterpret_cast<stor_priv_t<T> const &>(stor).val);
 }
 
 template<typename T>
@@ -28,19 +34,23 @@ static inline void csv_cleanup(cs_value_type tv, T &stor) {
     }
 }
 
-cs_value::cs_value():
+cs_value::cs_value(cs_state &st): cs_value(*st.p_state) {}
+
+cs_value::cs_value(cs_shared_state &st):
     p_stor(), p_len(0), p_type(cs_value_type::Null)
-{}
+{
+    reinterpret_cast<stor_priv_t<void *> *>(&p_stor)->state = &st;
+}
 
 cs_value::~cs_value() {
     csv_cleanup(p_type, p_stor);
 }
 
-cs_value::cs_value(cs_value const &v): cs_value() {
+cs_value::cs_value(cs_value const &v): cs_value(*v.state()) {
     *this = v;
 }
 
-cs_value::cs_value(cs_value &&v): cs_value() {
+cs_value::cs_value(cs_value &&v): cs_value(*v.state()) {
     *this = std::move(v);
 }
 
@@ -375,8 +385,8 @@ bool cs_value::get_bool() const {
 
 /* stacked value for easy stack management */
 
-cs_stacked_value::cs_stacked_value(cs_ident *id):
-    cs_value(), p_a(nullptr), p_stack(), p_pushed(false)
+cs_stacked_value::cs_stacked_value(cs_state &cs, cs_ident *id):
+    cs_value(cs), p_a(nullptr), p_stack{cs}, p_pushed(false)
 {
     set_alias(id);
 }
diff --git a/src/cs_vm.cc b/src/cs_vm.cc
index 0947a0c..af39e8f 100644
--- a/src/cs_vm.cc
+++ b/src/cs_vm.cc
@@ -12,7 +12,7 @@ cs_strref::cs_strref(cs_shared_state &cs, ostd::string_range str):
     p_str = cs.strman->add(str);
 }
 
-cs_strref::cs_strref(cs_strref const &ref): p_str{ref.p_str}, p_state{ref.p_state}
+cs_strref::cs_strref(cs_strref const &ref): p_state{ref.p_state}, p_str{ref.p_str}
 {
     p_state->strman->ref(p_str);
 }
@@ -55,9 +55,9 @@ struct cs_cmd_internal {
     }
 };
 
-static inline void cs_push_alias(cs_ident *id, cs_ident_stack &st) {
+static inline void cs_push_alias(cs_state &cs, cs_ident *id, cs_ident_stack &st) {
     if (id->is_alias() && (id->get_index() >= MaxArguments)) {
-        cs_value nv;
+        cs_value nv{cs};
         cs_alias_internal::push_arg(static_cast<cs_alias *>(id), nv, st);
     }
 }
@@ -470,7 +470,7 @@ static inline void callcommand(
                 i = std::max(i + 1, numargs);
                 auto buf = ostd::appender<cs_string>();
                 cscript::util::tvals_concat(buf, ostd::iter(args, args + i), " ");
-                cs_value tv;
+                cs_value tv{cs};
                 tv.set_str(std::move(buf.get()));
                 cs_cmd_internal::call(cs, id, cs_value_r(&tv, &tv + 1), res);
                 return;
@@ -503,7 +503,7 @@ static inline void cs_call_alias(
     int callargs, int &nargs, int offset, int skip, uint32_t op
 ) {
     cs_ivar *anargs = static_cast<cs_ivar *>(cs.p_state->identmap[NumargsIdx]);
-    cs_ident_stack argstack[MaxArguments];
+    cs_valarray<cs_ident_stack, MaxArguments> argstack{cs};
     for(int i = 0; i < callargs; i++) {
         cs_alias_internal::push_arg(
             static_cast<cs_alias *>(cs.p_state->identmap[i]),
@@ -515,7 +515,7 @@ static inline void cs_call_alias(
     int oldflags = cs.identflags;
     cs.identflags |= a->get_flags()&CS_IDF_OVERRIDDEN;
     cs_identLink aliaslink = {
-        a, cs.p_callstack, (1<<callargs)-1, argstack
+        a, cs.p_callstack, (1<<callargs)-1, &argstack[0]
     };
     cs.p_callstack = &aliaslink;
     uint32_t *codep = reinterpret_cast<uint32_t *>(
@@ -609,8 +609,8 @@ static inline int cs_get_lookupu_type(
                 return CsIdFvar;
             case cs_ident_type::Command: {
                 arg.set_null();
-                cs_value buf[MaxArguments];
-                callcommand(cs, static_cast<cs_command *>(id), buf, arg, 0, true);
+                cs_valarray<cs_value, MaxArguments> buf{cs};
+                callcommand(cs, static_cast<cs_command *>(id), &buf[0], arg, 0, true);
                 force_arg(arg, op & CsCodeRetMask);
                 return -2; /* ignore */
             }
@@ -625,7 +625,7 @@ static uint32_t *runcode(cs_state &cs, uint32_t *code, cs_value &result) {
     result.set_null();
     RunDepthRef level{cs}; /* incr and decr on scope exit */
     int numargs = 0;
-    cs_value args[MaxArguments + MaxResults];
+    cs_valarray<cs_value, MaxArguments + MaxResults> args{cs};
     auto &chook = cs.get_call_hook();
     if (chook) {
         chook(cs);
@@ -716,9 +716,9 @@ static uint32_t *runcode(cs_state &cs, uint32_t *code, cs_value &result) {
 
             case CsCodeLocal: {
                 int numlocals = op >> 8, offset = numargs - numlocals;
-                cs_ident_stack locals[MaxArguments];
+                cs_valarray<cs_ident_stack, MaxArguments> locals{cs};
                 for (int i = 0; i < numlocals; ++i) {
-                    cs_push_alias(args[offset + i].get_ident(), locals[i]);
+                    cs_push_alias(cs, args[offset + i].get_ident(), locals[i]);
                 }
                 cs_do_and_cleanup([&]() {
                     code = runcode(cs, code, result);
@@ -1002,7 +1002,7 @@ static uint32_t *runcode(cs_state &cs, uint32_t *code, cs_value &result) {
                     cs.p_state->identmap[op >> 8]
                 );
                 if (!cs_is_arg_used(cs, a)) {
-                    cs_value nv;
+                    cs_value nv{cs};
                     cs_alias_internal::push_arg(
                         a, nv, cs.p_callstack->argstack[a->get_index()], false
                     );
@@ -1022,7 +1022,7 @@ static uint32_t *runcode(cs_state &cs, uint32_t *code, cs_value &result) {
                     id = cs.new_ident(arg.get_strr());
                 }
                 if ((id->get_index() < MaxArguments) && !cs_is_arg_used(cs, id)) {
-                    cs_value nv;
+                    cs_value nv{cs};
                     cs_alias_internal::push_arg(
                         static_cast<cs_alias *>(id), nv,
                         cs.p_callstack->argstack[id->get_index()], false
@@ -1383,7 +1383,7 @@ static uint32_t *runcode(cs_state &cs, uint32_t *code, cs_value &result) {
                 int offset = numargs - id->get_num_args();
                 result.force_null();
                 cs_cmd_internal::call(cs, id, cs_value_r(
-                    args + offset, args + offset + id->get_num_args()
+                    &args[0] + offset, &args[0] + offset + id->get_num_args()
                 ), result);
                 force_arg(result, op & CsCodeRetMask);
                 numargs = offset;
@@ -1420,7 +1420,7 @@ static uint32_t *runcode(cs_state &cs, uint32_t *code, cs_value &result) {
                     cscript::util::tvals_concat(buf, ostd::iter(
                         &args[offset], &args[offset + callargs]
                     ), " ");
-                    cs_value tv;
+                    cs_value tv{cs};
                     tv.set_str(std::move(buf.get()));
                     cs_cmd_internal::call(cs, id, cs_value_r(&tv, &tv + 1), result);
                 }
@@ -1498,7 +1498,7 @@ static uint32_t *runcode(cs_state &cs, uint32_t *code, cs_value &result) {
                     );
                 }
                 cs_call_alias(
-                    cs, static_cast<cs_alias *>(id), args, result, callargs,
+                    cs, static_cast<cs_alias *>(id), &args[0], result, callargs,
                     numargs, offset, 0, op
                 );
                 continue;
@@ -1516,7 +1516,7 @@ static uint32_t *runcode(cs_state &cs, uint32_t *code, cs_value &result) {
                     continue;
                 }
                 cs_call_alias(
-                    cs, static_cast<cs_alias *>(id), args, result, callargs,
+                    cs, static_cast<cs_alias *>(id), &args[0], result, callargs,
                     numargs, offset, 0, op
                 );
                 continue;
@@ -1569,9 +1569,9 @@ noid:
                         numargs = offset - 1;
                         continue;
                     case CsIdLocal: {
-                        cs_ident_stack locals[MaxArguments];
+                        cs_valarray<cs_ident_stack, MaxArguments> locals{cs};
                         for (size_t j = 0; j < size_t(callargs); ++j) {
-                            cs_push_alias(cs.force_ident(
+                            cs_push_alias(cs, cs.force_ident(
                                 args[offset + j]
                             ), locals[j]);
                         }
@@ -1634,7 +1634,7 @@ noid:
                             goto noid;
                         }
                         cs_call_alias(
-                            cs, a, args, result, callargs, numargs,
+                            cs, a, &args[0], result, callargs, numargs,
                             offset, 1, op
                         );
                         continue;
@@ -1684,10 +1684,10 @@ void cs_state::run(cs_ident *id, cs_value_r args, cs_value &ret) {
             /* fallthrough */
             case cs_ident_type::Command:
                 if (nargs < static_cast<cs_command *>(id)->get_num_args()) {
-                    cs_value buf[MaxArguments];
-                    memcpy(buf, &args[0], args.size() * sizeof(cs_value));
+                    cs_valarray<cs_value, MaxArguments> buf{*this};
+                    memcpy(&buf[0], &args[0], args.size() * sizeof(cs_value));
                     callcommand(
-                        *this, static_cast<cs_command *>(id), buf, ret,
+                        *this, static_cast<cs_command *>(id), &buf[0], ret,
                         nargs, false
                     );
                 } else {
@@ -1743,89 +1743,89 @@ void cs_state::run(cs_ident *id, cs_value_r args, cs_value &ret) {
 }
 
 cs_string cs_state::run_str(cs_bcode *code) {
-    cs_value ret;
+    cs_value ret{*this};
     run(code, ret);
     return ret.get_str();
 }
 
 cs_string cs_state::run_str(ostd::string_range code) {
-    cs_value ret;
+    cs_value ret{*this};
     run(code, ret);
     return ret.get_str();
 }
 
 cs_string cs_state::run_str(cs_ident *id, cs_value_r args) {
-    cs_value ret;
+    cs_value ret{*this};
     run(id, args, ret);
     return ret.get_str();
 }
 
 cs_int cs_state::run_int(cs_bcode *code) {
-    cs_value ret;
+    cs_value ret{*this};
     run(code, ret);
     return ret.get_int();
 }
 
 cs_int cs_state::run_int(ostd::string_range code) {
-    cs_value ret;
+    cs_value ret{*this};
     run(code, ret);
     return ret.get_int();
 }
 
 cs_int cs_state::run_int(cs_ident *id, cs_value_r args) {
-    cs_value ret;
+    cs_value ret{*this};
     run(id, args, ret);
     return ret.get_int();
 }
 
 cs_float cs_state::run_float(cs_bcode *code) {
-    cs_value ret;
+    cs_value ret{*this};
     run(code, ret);
     return ret.get_float();
 }
 
 cs_float cs_state::run_float(ostd::string_range code) {
-    cs_value ret;
+    cs_value ret{*this};
     run(code, ret);
     return ret.get_float();
 }
 
 cs_float cs_state::run_float(cs_ident *id, cs_value_r args) {
-    cs_value ret;
+    cs_value ret{*this};
     run(id, args, ret);
     return ret.get_float();
 }
 
 bool cs_state::run_bool(cs_bcode *code) {
-    cs_value ret;
+    cs_value ret{*this};
     run(code, ret);
     return ret.get_bool();
 }
 
 bool cs_state::run_bool(ostd::string_range code) {
-    cs_value ret;
+    cs_value ret{*this};
     run(code, ret);
     return ret.get_bool();
 }
 
 bool cs_state::run_bool(cs_ident *id, cs_value_r args) {
-    cs_value ret;
+    cs_value ret{*this};
     run(id, args, ret);
     return ret.get_bool();
 }
 
 void cs_state::run(cs_bcode *code) {
-    cs_value ret;
+    cs_value ret{*this};
     run(code, ret);
 }
 
 void cs_state::run(ostd::string_range code) {
-    cs_value ret;
+    cs_value ret{*this};
     run(code, ret);
 }
 
 void cs_state::run(cs_ident *id, cs_value_r args) {
-    cs_value ret;
+    cs_value ret{*this};
     run(id, args, ret);
 }
 
@@ -1847,7 +1847,7 @@ CsLoopState cs_state::run_loop(cs_bcode *code, cs_value &ret) {
 }
 
 CsLoopState cs_state::run_loop(cs_bcode *code) {
-    cs_value ret;
+    cs_value ret{*this};
     return run_loop(code, ret);
 }
 
@@ -1879,7 +1879,7 @@ static bool cs_run_file(
 }
 
 std::optional<cs_string> cs_state::run_file_str(ostd::string_range fname) {
-    cs_value ret;
+    cs_value ret{*this};
     if (!cs_run_file(*this, fname, ret)) {
         return std::nullopt;
     }
@@ -1887,7 +1887,7 @@ std::optional<cs_string> cs_state::run_file_str(ostd::string_range fname) {
 }
 
 std::optional<cs_int> cs_state::run_file_int(ostd::string_range fname) {
-    cs_value ret;
+    cs_value ret{*this};
     if (!cs_run_file(*this, fname, ret)) {
         return std::nullopt;
     }
@@ -1895,7 +1895,7 @@ std::optional<cs_int> cs_state::run_file_int(ostd::string_range fname) {
 }
 
 std::optional<cs_float> cs_state::run_file_float(ostd::string_range fname) {
-    cs_value ret;
+    cs_value ret{*this};
     if (!cs_run_file(*this, fname, ret)) {
         return std::nullopt;
     }
@@ -1903,7 +1903,7 @@ std::optional<cs_float> cs_state::run_file_float(ostd::string_range fname) {
 }
 
 std::optional<bool> cs_state::run_file_bool(ostd::string_range fname) {
-    cs_value ret;
+    cs_value ret{*this};
     if (!cs_run_file(*this, fname, ret)) {
         return std::nullopt;
     }
@@ -1915,7 +1915,7 @@ bool cs_state::run_file(ostd::string_range fname, cs_value &ret) {
 }
 
 bool cs_state::run_file(ostd::string_range fname) {
-    cs_value ret;
+    cs_value ret{*this};
     if (!cs_run_file(*this, fname, ret)) {
         return false;
     }
diff --git a/src/cs_vm.hh b/src/cs_vm.hh
index 3d3c979..506152a 100644
--- a/src/cs_vm.hh
+++ b/src/cs_vm.hh
@@ -6,6 +6,7 @@
 #include <cstdlib>
 #include <array>
 #include <vector>
+#include <type_traits>
 
 #include "cs_util.hh"
 
@@ -31,6 +32,27 @@ struct cs_identLink {
     cs_ident_stack *argstack;
 };
 
+template<typename T, std::size_t N>
+struct cs_valarray {
+    cs_valarray(cs_state &cs) {
+        for (std::size_t i = 0; i < N; ++i) {
+            new (&stor[i]) T{cs};
+        }
+    }
+
+    ~cs_valarray() {
+        for (std::size_t i = 0; i < N; ++i) {
+            reinterpret_cast<T *>(&stor[i])->~T();
+        }
+    }
+
+    T &operator[](std::size_t i) {
+        return *reinterpret_cast<T *>(&stor[i]);
+    }
+
+    std::aligned_storage_t<sizeof(T), alignof(T)> stor[N];
+};
+
 enum {
     CsValNull = 0, CsValInt, CsValFloat, CsValString,
     CsValAny, CsValCode, CsValMacro, CsValIdent, CsValCstring,
@@ -409,7 +431,7 @@ static void cs_do_args(cs_state &cs, F body) {
         body();
         return;
     }
-    cs_ident_stack argstack[MaxArguments];
+    cs_valarray<cs_ident_stack, MaxArguments> argstack{cs};
     int argmask1 = cs.p_callstack->usedargs;
     for (int i = 0; argmask1; argmask1 >>= 1, ++i) {
         if (argmask1 & 1) {
diff --git a/src/cubescript.cc b/src/cubescript.cc
index e4e3f86..a631404 100644
--- a/src/cubescript.cc
+++ b/src/cubescript.cc
@@ -57,31 +57,32 @@ cs_svar::cs_svar(ostd::string_range name, cs_string v, cs_var_cb f, int fl):
     p_storage(std::move(v)), p_overrideval()
 {}
 
-cs_alias::cs_alias(ostd::string_range name, cs_string a, int fl):
+cs_alias::cs_alias(cs_state &cs, ostd::string_range name, cs_string a, int fl):
     cs_ident(cs_ident_type::Alias, name, fl),
-    p_acode(nullptr), p_astack(nullptr)
+    p_acode(nullptr), p_astack(nullptr), p_val{cs}
 {
     p_val.set_str(std::move(a));
 }
-cs_alias::cs_alias(ostd::string_range name, cs_int a, int fl):
+cs_alias::cs_alias(cs_state &cs, ostd::string_range name, cs_int a, int fl):
     cs_ident(cs_ident_type::Alias, name, fl),
-    p_acode(nullptr), p_astack(nullptr)
+    p_acode(nullptr), p_astack(nullptr), p_val{cs}
 {
     p_val.set_int(a);
 }
-cs_alias::cs_alias(ostd::string_range name, cs_float a, int fl):
+cs_alias::cs_alias(cs_state &cs, ostd::string_range name, cs_float a, int fl):
     cs_ident(cs_ident_type::Alias, name, fl),
-    p_acode(nullptr), p_astack(nullptr)
+    p_acode(nullptr), p_astack(nullptr), p_val{cs}
 {
     p_val.set_float(a);
 }
-cs_alias::cs_alias(ostd::string_range name, int fl):
+cs_alias::cs_alias(cs_state &cs, ostd::string_range name, int fl):
     cs_ident(cs_ident_type::Alias, name, fl),
-    p_acode(nullptr), p_astack(nullptr)
+    p_acode(nullptr), p_astack(nullptr), p_val{cs}
 {
     p_val.set_null();
 }
-cs_alias::cs_alias(ostd::string_range name, cs_value v, int fl):
+/* FIXME: use cs rather than val's cs */
+cs_alias::cs_alias(cs_state &, ostd::string_range name, cs_value v, int fl):
     cs_ident(cs_ident_type::Alias, name, fl),
     p_acode(nullptr), p_astack(nullptr), p_val(std::move(v))
 {}
@@ -522,7 +523,7 @@ OSTD_EXPORT cs_ident *cs_state::new_ident(ostd::string_range name, int flags) {
                 *this, "number %s is not a valid identifier name", name
             );
         }
-        id = add_ident(p_state->create<cs_alias>(name, flags));
+        id = add_ident(p_state->create<cs_alias>(*this, name, flags));
     }
     return id;
 }
@@ -650,7 +651,9 @@ OSTD_EXPORT void cs_state::set_alias(ostd::string_range name, cs_value v) {
     } else if (cs_check_num(name)) {
         throw cs_error(*this, "cannot alias number %s", name);
     } else {
-        add_ident(p_state->create<cs_alias>(name, std::move(v), identflags));
+        add_ident(p_state->create<cs_alias>(
+            *this, name, std::move(v), identflags
+        ));
     }
 }
 
@@ -1028,7 +1031,7 @@ static inline void cs_do_loop(
     cs_state &cs, cs_ident &id, cs_int offset, cs_int n, cs_int step,
     cs_bcode *cond, cs_bcode *body
 ) {
-    cs_stacked_value idv{&id};
+    cs_stacked_value idv{cs, &id};
     if (n <= 0 || !idv.has_alias()) {
         return;
     }
@@ -1053,7 +1056,7 @@ static inline void cs_loop_conc(
     cs_state &cs, cs_value &res, cs_ident &id, cs_int offset, cs_int n,
     cs_int step, cs_bcode *body, bool space
 ) {
-    cs_stacked_value idv{&id};
+    cs_stacked_value idv{cs, &id};
     if (n <= 0 || !idv.has_alias()) {
         return;
     }
@@ -1061,7 +1064,7 @@ static inline void cs_loop_conc(
     for (cs_int i = 0; i < n; ++i) {
         idv.set_int(offset + i * step);
         idv.push();
-        cs_value v;
+        cs_value v{cs};
         switch (cs.run_loop(body, v)) {
             case CsLoopState::Break:
                 goto end;
@@ -1091,7 +1094,7 @@ void cs_init_lib_base(cs_state &gcs) {
             ret.set_int(0);
             return;
         }
-        cs_value result, tback;
+        cs_value result{cs}, tback{cs};
         bool rc = true;
         try {
             cs.run(args[0].get_code(), result);
@@ -1171,7 +1174,7 @@ void cs_init_lib_base(cs_state &gcs) {
     });
 
     gcs.new_command("pushif", "rTe", [](auto &cs, auto args, auto &res) {
-        cs_stacked_value idv{args[0].get_ident()};
+        cs_stacked_value idv{cs, args[0].get_ident()};
         if (!idv.has_alias() || (idv.get_alias()->get_index() < MaxArguments)) {
             return;
         }
@@ -1315,7 +1318,7 @@ end:
     });
 
     gcs.new_command("push", "rTe", [](auto &cs, auto args, auto &res) {
-        cs_stacked_value idv{args[0].get_ident()};
+        cs_stacked_value idv{cs, args[0].get_ident()};
         if (!idv.has_alias() || (idv.get_alias()->get_index() < MaxArguments)) {
             return;
         }
diff --git a/src/lib_list.cc b/src/lib_list.cc
index 7a3ce24..c383e16 100644
--- a/src/lib_list.cc
+++ b/src/lib_list.cc
@@ -73,7 +73,7 @@ static void cs_loop_list_conc(
     cs_state &cs, cs_value &res, cs_ident *id, ostd::string_range list,
     cs_bcode *body, bool space
 ) {
-    cs_stacked_value idv{id};
+    cs_stacked_value idv{cs, id};
     if (!idv.has_alias()) {
         return;
     }
@@ -85,7 +85,7 @@ static void cs_loop_list_conc(
         if (n && space) {
             r += ' ';
         }
-        cs_value v;
+        cs_value v{cs};
         switch (cs.run_loop(body, v)) {
             case CsLoopState::Break:
                 goto end;
@@ -197,7 +197,7 @@ void cs_init_lib_list(cs_state &gcs) {
     });
 
     gcs.new_command("listfind", "rse", [](auto &cs, auto args, auto &res) {
-        cs_stacked_value idv{args[0].get_ident()};
+        cs_stacked_value idv{cs, args[0].get_ident()};
         if (!idv.has_alias()) {
             res.set_int(-1);
             return;
@@ -217,7 +217,7 @@ void cs_init_lib_list(cs_state &gcs) {
     });
 
     gcs.new_command("listassoc", "rse", [](auto &cs, auto args, auto &res) {
-        cs_stacked_value idv{args[0].get_ident()};
+        cs_stacked_value idv{cs, args[0].get_ident()};
         if (!idv.has_alias()) {
             return;
         }
@@ -284,7 +284,7 @@ void cs_init_lib_list(cs_state &gcs) {
     });
 
     gcs.new_command("looplist", "rse", [](auto &cs, auto args, auto &) {
-        cs_stacked_value idv{args[0].get_ident()};
+        cs_stacked_value idv{cs, args[0].get_ident()};
         if (!idv.has_alias()) {
             return;
         }
@@ -305,7 +305,8 @@ end:
     });
 
     gcs.new_command("looplist2", "rrse", [](auto &cs, auto args, auto &) {
-        cs_stacked_value idv1{args[0].get_ident()}, idv2{args[1].get_ident()};
+        cs_stacked_value idv1{cs, args[0].get_ident()};
+        cs_stacked_value idv2{cs, args[1].get_ident()};
         if (!idv1.has_alias() || !idv2.has_alias()) {
             return;
         }
@@ -332,9 +333,9 @@ end:
     });
 
     gcs.new_command("looplist3", "rrrse", [](auto &cs, auto args, auto &) {
-        cs_stacked_value idv1{args[0].get_ident()};
-        cs_stacked_value idv2{args[1].get_ident()};
-        cs_stacked_value idv3{args[2].get_ident()};
+        cs_stacked_value idv1{cs, args[0].get_ident()};
+        cs_stacked_value idv2{cs, args[1].get_ident()};
+        cs_stacked_value idv3{cs, args[2].get_ident()};
         if (!idv1.has_alias() || !idv2.has_alias() || !idv3.has_alias()) {
             return;
         }
@@ -383,7 +384,7 @@ end:
     });
 
     gcs.new_command("listfilter", "rse", [](auto &cs, auto args, auto &res) {
-        cs_stacked_value idv{args[0].get_ident()};
+        cs_stacked_value idv{cs, args[0].get_ident()};
         if (!idv.has_alias()) {
             return;
         }
@@ -404,7 +405,7 @@ end:
     });
 
     gcs.new_command("listcount", "rse", [](auto &cs, auto args, auto &res) {
-        cs_stacked_value idv{args[0].get_ident()};
+        cs_stacked_value idv{cs, args[0].get_ident()};
         if (!idv.has_alias()) {
             return;
         }
@@ -555,7 +556,7 @@ static void cs_list_sort(
         return;
     }
 
-    cs_stacked_value xval{xa}, yval{ya};
+    cs_stacked_value xval{cs, xa}, yval{cs, ya};
     xval.set_null();
     yval.set_null();
     xval.push();
diff --git a/tools/repl.cc b/tools/repl.cc
index 027d5a4..5a79d0d 100644
--- a/tools/repl.cc
+++ b/tools/repl.cc
@@ -188,7 +188,7 @@ static void do_sigint(int n) {
 }
 
 static bool do_call(cs_state &cs, ostd::string_range line, bool file = false) {
-    cs_value ret;
+    cs_value ret{cs};
     scs = &cs;
     signal(SIGINT, do_sigint);
     try {