Remove Unnecessary Initialisation of _paused

[pcaversaccio]

This PR removes the unnecessary initialisation of _paused. The state variable is already set at compile-time to false here:

openzeppelin-contracts/contracts/utils/Pausable.sol

Line 18 in 332bcb5

bool private _paused;

Not sure if this requires a changeset. Feel free to push one.

[changeset-bot]

🦋 Changeset detected

Latest commit: 5184b31

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openzeppelin-solidity	Minor

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[ernestognw]

Hi @pcaversaccio,

This change makes sense but the code pre-dates me so I wonder if I'm missing something. Also, this is strictly breaking but I wouldn't worry too much since it's easy to workaround and doesn't break smart contract upgrades.

Let's see if @Amxx has something to add.

[Amxx]

It also pre-dates me 😄

To me there are 2 things to consider:

• "normal" contracts: the storage should definitelly be empty at construction, so setting it to false should have no effect. A good optimiser may remove that sstore, though I'm not sure it is the case.
  • The price of warming up the slot, an writting 0 to it, when it already contains 0, is 2200 gas (if the slot is not shared)
• upgradeable contracts: if Pausing is added during an upgrade, the slot may be non-zero. In that case an initializer would do the clean up so that there is no risk the contract is paused by default.
  • With namespace storage, the likelyhood of this happening is extremelly low !

I'd be ok with that change. But I'm also curious if @frangio knows more about what we have that in the first place ?

[Amxx]

CI confirms, the optimizer doesn't remove that, so the change indeed saves +2k gas on deployment

[pcaversaccio]

I did some research. The PR that added the change: #1403 & the issue from Nico: #1391. Previously it was like:

bool private _paused = false;

And since we all like memes and we should have more fun in life, I simply drop this here 😄:

[ernestognw]

upgradeable contracts: if Pausing is added during an upgrade, the slot may be non-zero. In that case an initializer would do the clean up so that there is no risk the contract is paused by default.
With namespace storage, the likelyhood of this happening is extremelly low !

I was thinking something similar but I also don't see it happening with namespace storage.

[frangio]

bool private _paused = false;

Yeah this was the original code and it was just meant to be explicit and carried over until today. I think it's fine to remove it.