DCIPs/EIPS/eip-1285.md

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---
eip: 1285
title: Increase Gcallstipend gas in the CALL opcode
author: Ben Kaufman <ben@daostack.io>, Adam Levi <adam@daostack.io>
discussions-to: https://ethereum-magicians.org/t/eip-1285-increase-gcallstipend-gas-in-the-call-opcode/941
status: Stagnant
type: Standards Track
category: Core
created: 2018-08-01
---
## Simple Summary
Increase the ``Gcallstipend`` fee parameter in the ``CALL`` opcode from ``2,300`` to ``3,500`` gas units.
## Abstract
Currently, the ``CALL`` opcode forwards a stipend of ``2,300`` gas units for a non zero value ``CALL`` operations where a contract is called. This stipend is given to the contract to allow execution of its ``fallback`` function. The stipend given is intentionally small in order to prevent the called contract from spending the call gas or performing an attack (like re-entrancy).
While the stipend is small it should still give the sufficient gas required for some cheap opcodes like ``LOG``, but it's not enough for some more complex and modern logics to be implemented.
This EIP proposes to increase the given stipend from ``2,300`` to ``3,500`` to increase the usability of the ``fallback`` function.
## Motivation
The main motivation behind this EIP is to allow simple fallback functions to be implemented for contracts following the ``"Proxy"`` pattern. Simply explained, a ``"Proxy Contract"`` is a contract which use ``DELEGATECALL`` in its ``fallback`` function to behave according to the logic of another contract and serve as an independent instance for the logic of the contract it points to.
This pattern is very useful for saving gas per deployment (as Proxy contracts are very lean) and it opens the ability to experiment with upgradability of contracts.
On average, the ``DELEGATECALL`` functionality of a proxy contract costs about ``1,000`` gas units.
When a contract transfers ETH to a proxy contract, the proxy logic will consume about ``1,000`` gas units before the ``fallback`` function of the logic contract will be executed. This leaves merely about 1,300 gas units for the execution of the logic. This is a severe limitation as it is not enough for an average ``LOG`` operation (it might be enough for a ``LOG`` with one parameter).
By slightly increasing the gas units given in the stipend we allow proxy contracts have proper ``fallback`` logic without increasing the attack surface of the calling contract.
## Specification
Increase the ``Gcallstipend`` fee parameter in the ``CALL`` opcode from ``2,300`` to ``3,500`` gas unit.
The actual change to the Ethereum clients would be to change the ``CallStipend`` they store as a constant.
For an implementation example you can find a Geth client implementation linked [here](https://github.com/ben-kaufman/go-ethereum/tree/eip-1285). The actual change to the code can be found [here](https://github.com/ben-kaufman/go-ethereum/blob/eip-1285/params/protocol_params.go#L41).
## Rationale
The rational for increasing the ``Gcallstipend`` gas parameter by ``1,200`` gas units comes from the cost of performing ``DELEGATECALL`` and ``SLOAD`` with a small margin for some small additional operations. All while still keeping the stipend relatively small and insufficient for accessing the storage or changing the state.
## Backwards Compatibility
This EIP requires a backwards incompatible change for the ``Gcallstipend`` gas parameter in the ``CALL`` opcode.
## Copyright
Copyright and related rights waived via [CC0](../LICENSE.md).