Add support for solc 0.8.20 and set default to Shanghai

[pcaversaccio]

solc 0.8.20 just got released https://github.com/ethereum/solidity/releases/tag/v0.8.20

Edit: Added scope to setting default to Shanghai.

[mattsse]

fyi @roynalnaruto

[Evalir]

sick—we can get to this as soon as ethers gets a bump with 0.8.20 support. Ideally it would set Shanghai as the default EVM version too, so we can move over everything to it as well to be in line with the rest of the ecosystem. ( cc @DaniPopes )

[pcaversaccio]

FYI (for the ones interested), I also added solc 0.8.20 support for dapptools here dapphub/dapptools#984.

[DaniPopes]

Set default to "Shanghai" and added support for the PUSH0 opcode: gakonst/ethers-rs#2414
Blocked on SVM.

[Evalir]

this was done in #4975 — should we close this and track the actual upgrade to Shanghai as default as a separate issue or edit this one?

[pcaversaccio]

Let's stick to this issue if everyone agrees, so it's easy to find for anyone who searches for the upgrade and default setting to Shanghai. Will update the title of my issue accordingly (Edit: DONE).

[dionysuzx]

when saying "set the default to Shanghai" does this mean 1) the compiler will target shanghai without needing to specify evm_version and 2) that anvil will also use the shanghai EVM? and i'm also curious is shanghai available for anvil now (as a non-default) and if not how do i know which EVM version anvil is running?

and one question.. what is the default evm_version now for foundry when compiling? paris? i was thinking it might be nice to have some version flag on forge / anvil cli to see which evm version is set.

[Evalir]

Hey @d1onys1us — great questions. This means N1. N2 is actually being done right now on this PR: #5001.

The current default EVM Version is Paris, but will be set to shanghai after ethers-rs is bumped with it as default.

[pcaversaccio]

what's the status here?

[dionysuzx]

what's the status here?

adding to this--how do I know if anvil is running --shanghai by default? when i do cast block against either anvil or anvil --hardfork shanghai, I am not seeing withdrawalsRoot returned in the block data.

[Evalir]

We've added support for 0.8.20, but decided to keep forge on Paris as default to avoid more compatibility issues. Will be closing this.

@d1onys1us will be opening your comment as a separate issue

[AmazingAng]

How to set the test environment of Foundry to Shanghai Upgrade?

[pcaversaccio]

You can do this in the foundry.toml via the evm_version option; example https://github.com/pcaversaccio/snekmate/blob/main/foundry.toml#L16.

[AmazingAng]

You can do this in the foundry.toml via the evm_version option; example https://github.com/pcaversaccio/snekmate/blob/main/foundry.toml#L16.

Thanks, I solved it using --evm-version shanghai in cmd.
But we not set default to shanghai?
The Paris version does not support PUSH0 opcode, which is not good.

[pcaversaccio]

Thanks, I solved it using --evm-version shanghai in cmd.
But we not set default to shanghai?
The Paris version does not support PUSH0 opcode, which is not good.

No, too many EVM-based chains do currently not support PUSH0, which would lead to a deployment or even runtime revert if compiled via shanghai. Until the to 10 chains in terms of TVL don't support shanghai, it's a good choice to default to paris.