c4-judge
commented
1 year ago Picodes marked the issue as grade-b
Open code423n4 opened 1 year ago
c4-judge
commented
1 year ago Picodes marked the issue as grade-b
Picodes
commented
1 year ago Lots of now out of scope findings with the automated report
[G01] State variables only set in the constructor should be declared
immutableImpact
Avoids a Gsset (20000 gas)
Findings:
[G02] State variables can be packed into fewer storage slots
Impact
If variables occupying the same slot are both written the same function or by the constructor, avoids a separate Gsset (20000 gas). Reads of the variables are also cheaper
Findings:
[G03]
<array>.lengthshould not be looked up in every loop of aforloopImpact
Even memory arrays incur the overhead of bit tests and bit shifts to calculate the array length. Storage array length checks incur an extra Gwarmaccess (100 gas) PER-LOOP.
Findings:
[G04]
++i/i++should beunchecked{++i}/unchecked{++i}when it is not possible for them to overflow, as is the case when used inforandwhileloopsFindings:
[G05] Not using the named return variables when a function returns, wastes deployment gas
Findings:
[G06] Using
> 0costs more gas than!= 0when used on auintin arequire()statementFindings:
[G07] It costs more gas to initialize variables to zero than to let the default of zero be applied
Findings:
[G08]
++icosts less gas thani++, especially when it’s used in forloops (--i/i--too)Findings:
[G09] Functions guaranteed to revert when called by normal users can be marked
payableImpact
If a function modifier such as onlyOwner is used, the function will revert if a normal user tries to pay the function. Marking the function as payable will lower the gas cost for legitimate callers because the compiler will not include checks for whether a payment was provided.
Findings:
[G10] Use
calldatainstead ofmemoryfor function parametersImpact
Use calldata instead of memory for function parameters. Having function arguments use calldata instead of memory can save gas.
Findings:
[G11] Multiple
addressmappings can be combined into a singlemappingof anaddressto astruct, where appropriateImpact
Saves a storage slot for the mapping. Depending on the circumstances and sizes of types, can avoid a Gsset (20000 gas) per mapping combined. Reads and subsequent writes can also be cheaper when a function requires both values and they both fit in the same storage slot
Findings:
[G12] Using
boolsfor storage incurs overheadFindings:
[G13] Remove or replace unused state variables
Impact
Saves a storage slot. If the variable is assigned a non-zero value, saves Gsset (20000 gas). If it’s assigned a zero value, saves Gsreset (2900 gas). If the variable remains unassigned, there is no gas savings unless the variable is public, in which case the compiler-generated non-payable getter deployment cost is saved. If the state variable is overriding an interface’s public function, mark the variable as constant or immutable so that it does not use a storage slot
Findings:
[G14] Optimize names to save gas
Impact
public/external function names and public member variable names can be optimized to save gas. See this link for an example of how it works. Below are the interfaces/abstract contracts that can be optimized so that the most frequently-called functions use the least amount of gas possible during method lookup.
Findings: