I have had two contracts (A, B), where contract a calls a function on contract b, when contract a is deployed. This works fine up to a certain point where I receive a contracts.ContractTrapped error (Usually after calling this function around 300-400 times)

When I redeploy contract B, with a new contractAddress, when I Initialize contract A with the new contractAddress, It obviously does work.

Also when I call the function that is called by contract A on contract B set_end_date I get the same contracts.contractTrapped error. So it is definitely an issue with contract B

That said I can read everything from contract B so it is not in the tombstone state!

This is the function being called on Contract B

    pub fn set_end_date(&mut self, end_date: u64) -> Result<()> {
        let caller = self.env().caller();
        self.end_date.insert(caller, end_date);

I really suspect this is an issue perhaps with the amount of storage a given key can have on the contracts pallet, but was curious if anyone else has had this issue and can point me in the right direction!

Follow up

I ran a loop to see when this issue starts happening and it happens at the 408th time the function on contract b (set_end_date) is being called. I strongly suspect that this is an issue for how much storage a mapping can contain on the contracts pallet, will keep you posted!

  • are you calling the function with different caller every time? Or what is the type of the end_date field?
    – kriko.eth
    Feb 23, 2023 at 9:31
  • @kriko727, I am not individually calling the set_end_date, rather I am deploying a smart contract, which in its constructor calls the set_end_date function. So the caller of the set_end_date is the deployed contract! That said I have after the fact also called it with various different accounts and this issue persists! the end_date field is as follows: end_date: BTreeMap<AccountId, u64>, Simply a mapping of an address to a timestamp!
    Feb 23, 2023 at 12:05
  • okay, so you deploy a contract, the contract calls B::set_end_date right? And you deploy 408 contracts, is that correct?
    – kriko.eth
    Feb 23, 2023 at 15:54

2 Answers 2


It is indeed an issue with the storage, as the BTreeMap is a Packed struct, therefore being contained within one cell (see doc: https://use.ink/datastructures/mapping)

  • Thanks Kriko, It was indeed this, made my week!
    Feb 27, 2023 at 13:28

Contract Trapped During Exucution error while cross-contract calling issue occur because I guess you haven't instantiated contract which you are calling. I have produced this error why contracts.ContractTrapped issue occurs and also solve it. you can view this code example here and you can also docs of this contract here

  • Thanks for the response! but I don't think this is the case, I am correctly calling the contract B when contract A is being deployed. I actually just ran some tests on how many times contract a calls the function b before there is an error, and it happens on the 408th time the function is called. I will leave a more in depth follow up above!
    Feb 22, 2023 at 15:26
  • if possible can you please send code link?
    – Ganesh11
    Feb 22, 2023 at 15:34
  • Thank you guys, But the issue was me using BTreeMap!
    Feb 27, 2023 at 13:27

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