Description

Hi, we recently find an issue when compiling safe-contracts in our test suite using the latest version of the Solidity compiler with the yul optimizer enabled. You can read more details and discussions about the issue here: argotorg/solidity#14082

In summary, it throws stack too deep error (see below) when using the following compiler settings: {"viaIR":true,"optimizer":{"enabled":true, "details": {"yul": true}}}

The problem was introduced by this commit: b9fdbde

Environment

• Compiler version: 0.8.19
• Compiler settings: evmVersion: 'paris', viaIR: true, optimizer: {enabled: true, details: {yul: true}}}

Steps to Reproduce

Set the .env to:

SOLIDITY_VERSION="0.8.19"
SOLIDITY_SETTINGS='{"viaIR":true,"optimizer":{"enabled":true, "details": {"yul": true}}}'

And run: yarn build. This will produce the following error:

YulException: Cannot swap Variable var_operation with Variable _1: too deep in the stack by 4 slots in [ var_operation RET var_operation var_data_length var_signatures_mpos var_signatures_mpos var_to var_refundReceiver var_gasToken var_gasPrice var_baseGas var_safeTxGas var_value var_data_174_offset var_refundReceiver var_to var_data_length var_value var_gasToken var_gasPrice var_baseGas var_safeTxGas _1 ]
No memoryguard was present. Consider using memory-safe assembly only and annotating it via 'assembly ("memory-safe") { ... }'.


Error HH600: Compilation failed

Possible solution

Add the "memory-safe" annotation to assembly code blocks when needed.