diff --git a/test/tables/trees2.lua b/test/tables/trees2.lua
index e6cf9a95..68156ff6 100644
--- a/test/tables/trees2.lua
+++ b/test/tables/trees2.lua
@@ -12,11 +12,16 @@ end
 
 local function ItemCheck(tree)
     if #tree == 3 then
-        return tree[1] + ItemCheck(tree[2]) - ItemCheck(tree[3])
+        local v1 = tree[1]
+        local v2 = ItemCheck(tree[2])
+        local v3 = ItemCheck(tree[3])
+        print(v1, v2, v3)
+        return v1 + v2 - v3
     else
+        print(tree[1])
         return tree[1]
     end
 end
 
-local stretchtree = BottomUpTree(0, 12)
+local stretchtree = BottomUpTree(0, 3)
 print(ItemCheck(stretchtree))
diff --git a/vm/backend/exec.c b/vm/backend/exec.c
index 4492d176..788b73f3 100644
--- a/vm/backend/exec.c
+++ b/vm/backend/exec.c
@@ -73,12 +73,13 @@ void *vm_cache_comp(const char *comp, const char **srcs, const char *entry) {
         fwrite(src_buf->buf, src_buf->len, 1, out);
         fclose(out);
         vm_io_buffer_t *cmd_buf = vm_io_buffer_new();
-        vm_io_buffer_format(cmd_buf, "%s -shared -O2 -foptimize-sibling-calls -fPIC %s -o %s -w -pipe", comp, c_file, so_file);
+        // vm_io_buffer_format(cmd_buf, "%s -shared -O2 -foptimize-sibling-calls -fPIC %s -o %s -w -pipe", comp, c_file, so_file);
+        vm_io_buffer_format(cmd_buf, "%s -shared -g2 -foptimize-sibling-calls -fPIC %s -o %s -w -pipe", comp, c_file, so_file);
         int res = system(cmd_buf->buf);
         if (res) {
             return NULL;
         }
-        remove(c_file);
+        // remove(c_file);
     }
     void *handle = dlopen(so_file, RTLD_LAZY);
     void *sym = dlsym(handle, entry);
diff --git a/vm/config.h b/vm/config.h
index 54b26b5f..2e69a37b 100644
--- a/vm/config.h
+++ b/vm/config.h
@@ -5,7 +5,7 @@
 #include <stdbool.h>
 
 #define VM_USE_DUMP 1
-#define VM_NO_TAILCALL 0
+#define VM_NO_TAILCALL 1
 #define VM_FORMAT_FLOAT "%.14g"
 
 struct vm_config_t;
diff --git a/vm/ir/tag.h b/vm/ir/tag.h
index 9dfbc600..afe23a7c 100644
--- a/vm/ir/tag.h
+++ b/vm/ir/tag.h
@@ -33,7 +33,7 @@ struct vm_type_value_t {
     uint32_t tag;
 };
 
-extern const vm_type_value_t vm_type_base[VM_TAG_MAX];
+extern vm_type_value_t vm_type_base[VM_TAG_MAX];
 
 #define VM_TYPE_UNK (NULL)
 #define VM_TYPE_NIL (&vm_type_base[VM_TAG_NIL])
diff --git a/vm/ir/type.c b/vm/ir/type.c
index d02dac2e..ba3414c4 100644
--- a/vm/ir/type.c
+++ b/vm/ir/type.c
@@ -3,7 +3,7 @@
 
 #include "ir.h"
 
-const vm_type_value_t vm_type_base[VM_TAG_MAX] = {
+vm_type_value_t vm_type_base[VM_TAG_MAX] = {
     [VM_TAG_NIL] = {VM_TAG_NIL},
     [VM_TAG_BOOL] = {VM_TAG_BOOL},
     [VM_TAG_I8] = {VM_TAG_I8},