I would like to update this code, because it is CDT 1.2. I would like to update for CDT 1.5 or CDT 1.6. What do I need to change?

#include <eosiolib/eosio.hpp>
#include <eosiolib/currency.hpp>

using namespace eosio;

class hello : public eosio::contract {
      using contract::contract;

      hello(account_name self) : contract(self) {}

      /// @abi table 
      struct account {
          account_name owner;
          uint64_t balance;

          uint64_t primary_key() const { return owner; };

      typedef eosio::multi_index<N(account), account> accs; 

      /// @abi action 
      void addbalance(account_name owner, uint64_t amount) {
           accs accounts(_self, owner);
           auto existing = accounts.find(owner);

           if (existing == accounts.end())
               /* Add new account */
               accounts.emplace(_self, [&](auto& a) {
                   a.owner = owner;
                   a.balance = amount;
           } else {
               /* Update existing account */
               const auto& st = *existing;
               accounts.modify(st, 0, [&](auto& a) {
                   a.balance += amount;

      void on(const currency::transfer& t) {
          if (t.to == _self) {
              addbalance(t.from, t.quantity.amount);

      void use(account_name contract, account_name act) {
          if (act == N(transfer)) {

          auto& thiscontract = *this;
          switch( act ) {
             EOSIO_API( hello, (addbalance));

extern "C" {
   [[noreturn]] void apply( uint64_t receiver, uint64_t code, uint64_t action ) {
      hello  h( receiver );
      h.use( code, action );

You can use this official page to guide you on how to install the latest CDT


  • Thnak you. I saw, but I would like update beacuse I would like to us the CDT 1.6.
    – Efraim
    May 28 '19 at 7:47
  • Once you have done the step I gave you in the link, your compiler will try to compile to the 1.6.1 cdt, if it dont compile maybe you gonna have to change part of your code
    – Saxtheowl
    May 28 '19 at 12:31
  • ok I tried, but fatal error: 'eosiolib/currency.hpp' file not found..which file neeod too change in cdt 1.6?
    – Efraim
    May 28 '19 at 13:52
  • and affet a lot error, so I think I need change full code, or rewrite.
    – Efraim
    May 28 '19 at 14:00
  • Yes, you gonna have to rewrite part of your code, we can help you for general stuff about EOS but we dont know how your program work
    – Saxtheowl
    May 28 '19 at 14:21

This is a list of all changes to eosio.cdt at each version: https://github.com/EOSIO/eosio.cdt/releases

Start reading it from the version you are currently using until the version you want to migrate to. There was a large amount of breaking changes when going from v1.2.x to v1.3.x.

A lot of the libraries changes location and/or were deleted or merged. For example currency.hpp no longer exists, and the folder eosiolib is now deprecated. Any contracts written before v1.3 will require significant reworking.

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