Upgrade to solidity 0.8.7

integration-tests/contracts/ConstructorReverter.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 import { Reverter } from './Reverter.sol';
 

integration-tests/contracts/ERC20.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 contract ERC20 {
     event Transfer(address indexed _from, address indexed _to, uint256 _value);

integration-tests/contracts/OVMContextStorage.sol

 // SPDX-License-Identifier: MIT
 
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 // Can't do this until the package is published.
 //import { iOVM_L1BlockNumber } from "@eth-optimism/contracts/iOVM_L1BlockNumber";

integration-tests/contracts/OVMMulticall.sol

@@ -18,7 +18,7 @@ copies or substantial portions of the Software.
 
 */
 
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 // Can't do this until the package is published.
 //import { iOVM_L1BlockNumber } from "@eth-optimism/contracts/iOVM_L1BlockNumber";

integration-tests/contracts/Proxy.sol

 // SPDX-License-Identifier: MIT
 
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM

integration-tests/contracts/Reverter.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 contract Reverter {
     string constant public revertMessage = "This is a simple reversion.";

integration-tests/contracts/SimpleStorage.sol

-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 contract ICrossDomainMessenger {
     address public xDomainMessageSender;

integration-tests/contracts/TestOOG.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 contract TestOOG {
     function runOutOfGas() public {

integration-tests/contracts/ValueCalls.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 contract ValueContext {
     function getSelfBalance() external payable returns(uint256) {

integration-tests/hardhat.config.ts

@@ -16,7 +16,7 @@ const config: HardhatUserConfig = {
   mocha: {
     timeout: 50000,
   },
-  solidity: '0.8.4',
+  solidity: '0.8.7',
   gasReporter: {
     enabled: enableGasReport,
     currency: 'USD',

packages/batch-submitter/hardhat.config.ts

@@ -19,7 +19,7 @@ const config: HardhatUserConfig = {
     timeout: 50000,
   },
   solidity: {
-    version: '0.8.4',
+    version: '0.8.7',
     settings: {
       optimizer: {
         enabled: true,

packages/contracts/contracts/L1/messaging/IL1CrossDomainMessenger.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_OVMCodec } from "../../libraries/codec/Lib_OVMCodec.sol";

packages/contracts/contracts/L1/messaging/IL1ERC20Bridge.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title IL1ERC20Bridge

packages/contracts/contracts/L1/messaging/IL1StandardBridge.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 import "./IL1ERC20Bridge.sol";
 

packages/contracts/contracts/L1/messaging/L1CrossDomainMessenger.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_AddressResolver } from "../../libraries/resolver/Lib_AddressResolver.sol";

packages/contracts/contracts/L1/messaging/L1StandardBridge.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Interface Imports */
 import { IL1StandardBridge } from "./IL1StandardBridge.sol";

packages/contracts/contracts/L1/rollup/CanonicalTransactionChain.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_OVMCodec } from "../../libraries/codec/Lib_OVMCodec.sol";

packages/contracts/contracts/L1/rollup/ChainStorageContainer.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_Buffer } from "../../libraries/utils/Lib_Buffer.sol";

packages/contracts/contracts/L1/rollup/ICanonicalTransactionChain.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_OVMCodec } from "../../libraries/codec/Lib_OVMCodec.sol";

packages/contracts/contracts/L1/rollup/IChainStorageContainer.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title IChainStorageContainer

packages/contracts/contracts/L1/rollup/IStateCommitmentChain.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_OVMCodec } from "../../libraries/codec/Lib_OVMCodec.sol";

packages/contracts/contracts/L1/rollup/StateCommitmentChain.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_OVMCodec } from "../../libraries/codec/Lib_OVMCodec.sol";

packages/contracts/contracts/L1/verification/BondManager.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Interface Imports */
 import { IBondManager } from "./IBondManager.sol";

packages/contracts/contracts/L1/verification/IBondManager.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title IBondManager

packages/contracts/contracts/L2/messaging/IL2CrossDomainMessenger.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Interface Imports */
 import { ICrossDomainMessenger } from "../../libraries/bridge/ICrossDomainMessenger.sol";

packages/contracts/contracts/L2/messaging/IL2ERC20Bridge.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title IL2ERC20Bridge

packages/contracts/contracts/L2/messaging/L2CrossDomainMessenger.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_CrossDomainUtils } from "../../libraries/bridge/Lib_CrossDomainUtils.sol";

packages/contracts/contracts/L2/messaging/L2StandardBridge.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Interface Imports */
 import { IL1StandardBridge } from "../../L1/messaging/IL1StandardBridge.sol";

packages/contracts/contracts/L2/messaging/L2StandardTokenFactory.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Contract Imports */
 import { L2StandardERC20 } from "../../libraries/standards/L2StandardERC20.sol";

packages/contracts/contracts/L2/predeploys/OVM_DeployerWhitelist.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title OVM_DeployerWhitelist

packages/contracts/contracts/L2/predeploys/OVM_ETH.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_PredeployAddresses } from "../../libraries/constants/Lib_PredeployAddresses.sol";

packages/contracts/contracts/L2/predeploys/OVM_GasPriceOracle.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Internal Imports */
 import { iOVM_GasPriceOracle } from "./iOVM_GasPriceOracle.sol";

packages/contracts/contracts/L2/predeploys/OVM_L2ToL1MessagePasser.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Interface Imports */
 import { iOVM_L2ToL1MessagePasser } from "./iOVM_L2ToL1MessagePasser.sol";

packages/contracts/contracts/L2/predeploys/OVM_SequencerFeeVault.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_PredeployAddresses } from "../../libraries/constants/Lib_PredeployAddresses.sol";

packages/contracts/contracts/L2/predeploys/iOVM_L1BlockNumber.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title iOVM_L1BlockNumber

packages/contracts/contracts/L2/predeploys/iOVM_L1MessageSender.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title iOVM_L1MessageSender

packages/contracts/contracts/L2/predeploys/iOVM_L2ToL1MessagePasser.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title iOVM_L2ToL1MessagePasser

packages/contracts/contracts/chugsplash/L1ChugSplashProxy.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 import { iL1ChugSplashDeployer } from "./interfaces/iL1ChugSplashDeployer.sol";
 

packages/contracts/contracts/chugsplash/interfaces/iL1ChugSplashDeployer.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title iL1ChugSplashDeployer

packages/contracts/contracts/libraries/bridge/CrossDomainEnabled.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Interface Imports */
 import { ICrossDomainMessenger } from "./ICrossDomainMessenger.sol";

packages/contracts/contracts/libraries/bridge/ICrossDomainMessenger.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title ICrossDomainMessenger

packages/contracts/contracts/libraries/bridge/Lib_CrossDomainUtils.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_RLPReader } from "../rlp/Lib_RLPReader.sol";

packages/contracts/contracts/libraries/codec/Lib_OVMCodec.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_RLPReader } from "../rlp/Lib_RLPReader.sol";

packages/contracts/contracts/libraries/constants/Lib_DefaultValues.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title Lib_DefaultValues

packages/contracts/contracts/libraries/constants/Lib_PredeployAddresses.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title Lib_PredeployAddresses

packages/contracts/contracts/libraries/resolver/Lib_AddressManager.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* External Imports */
 import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";

packages/contracts/contracts/libraries/resolver/Lib_AddressResolver.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_AddressManager } from "./Lib_AddressManager.sol";

packages/contracts/contracts/libraries/resolver/Lib_ResolvedDelegateProxy.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_AddressManager } from "./Lib_AddressManager.sol";

packages/contracts/contracts/libraries/rlp/Lib_RLPReader.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title Lib_RLPReader

packages/contracts/contracts/libraries/rlp/Lib_RLPWriter.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title Lib_RLPWriter

packages/contracts/contracts/libraries/standards/IL2StandardERC20.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 import { IERC20 } from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 import { IERC165 } from "@openzeppelin/contracts/utils/introspection/IERC165.sol";

packages/contracts/contracts/libraries/standards/IWETH9.sol

 // SPDX-License-Identifier: GPL-2.0-or-later
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 
 /// @title Interface for WETH9. Also contains the non-ERC20 events

packages/contracts/contracts/libraries/standards/L2StandardERC20.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
 

packages/contracts/contracts/libraries/trie/Lib_MerkleTrie.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_BytesUtils } from "../utils/Lib_BytesUtils.sol";

packages/contracts/contracts/libraries/trie/Lib_SecureMerkleTrie.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_MerkleTrie } from "./Lib_MerkleTrie.sol";

packages/contracts/contracts/libraries/utils/Lib_Buffer.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title Lib_Buffer

packages/contracts/contracts/libraries/utils/Lib_Bytes32Utils.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title Lib_Byte32Utils

packages/contracts/contracts/libraries/utils/Lib_BytesUtils.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title Lib_BytesUtils

packages/contracts/contracts/libraries/utils/Lib_MerkleTree.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /**
  * @title Lib_MerkleTree

packages/contracts/contracts/test-helpers/Helper_GasMeasurer.sol

 // SPDX-License-Identifier: UNLICENSED
 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 contract Helper_GasMeasurer {
     function measureCallGas(

packages/contracts/contracts/test-helpers/Helper_SimpleProxy.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 contract Helper_SimpleProxy {
     address internal owner;

packages/contracts/contracts/test-helpers/TestERC20.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 // a test ERC20 token with an open mint function
 contract TestERC20 {

packages/contracts/contracts/test-libraries/codec/TestLib_OVMCodec.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_OVMCodec } from "../../libraries/codec/Lib_OVMCodec.sol";

packages/contracts/contracts/test-libraries/rlp/TestLib_RLPReader.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_RLPReader } from "../../libraries/rlp/Lib_RLPReader.sol";

packages/contracts/contracts/test-libraries/rlp/TestLib_RLPWriter.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_RLPWriter } from "../../libraries/rlp/Lib_RLPWriter.sol";

packages/contracts/contracts/test-libraries/trie/TestLib_MerkleTrie.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_MerkleTrie } from "../../libraries/trie/Lib_MerkleTrie.sol";

packages/contracts/contracts/test-libraries/trie/TestLib_SecureMerkleTrie.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_SecureMerkleTrie } from "../../libraries/trie/Lib_SecureMerkleTrie.sol";

packages/contracts/contracts/test-libraries/utils/TestLib_Buffer.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_Buffer } from "../../libraries/utils/Lib_Buffer.sol";

packages/contracts/contracts/test-libraries/utils/TestLib_Bytes32Utils.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_Bytes32Utils } from "../../libraries/utils/Lib_Bytes32Utils.sol";

packages/contracts/contracts/test-libraries/utils/TestLib_BytesUtils.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_BytesUtils } from "../../libraries/utils/Lib_BytesUtils.sol";

packages/contracts/contracts/test-libraries/utils/TestLib_MerkleTree.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 /* Library Imports */
 import { Lib_MerkleTree } from "../../libraries/utils/Lib_MerkleTree.sol";

packages/contracts/hardhat.config.ts

@@ -59,7 +59,7 @@ const config: HardhatUserConfig = {
   solidity: {
     compilers: [
       {
-        version: '0.7.6',
+        version: '0.8.7',
       },
       {
         version: '0.5.17', // Required for WETH9

packages/message-relayer/hardhat.config.ts

@@ -8,7 +8,7 @@ const config: HardhatUserConfig = {
     sources: './test/test-contracts',
   },
   solidity: {
-    version: '0.8.4',
+    version: '0.8.7',
   },
 }
 

packages/message-relayer/test/test-contracts/MockL2CrossDomainMessenger.sol

 // SPDX-License-Identifier: MIT
-pragma solidity ^0.8.4;
+pragma solidity ^0.8.7;
 
 contract MockL2CrossDomainMessenger {
     struct MessageData {