Blockchain Developer Certification Practice

What is the role of the stack in memory management within Solidity?

1. It stores persistent data

2. It holds small local variables

3. It contains function codes

4. It saves transaction history

The correct answer is: It holds small local variables

The stack in Solidity serves as a temporary storage area and is specifically designed for holding small local variables, such as those used within functions. When a function is executed, any local variables, intermediate computations, and parameters are stored on the stack, allowing for efficient access and manipulation during the function's execution. In contrast to persistent data, which is stored in the contract's storage or the blockchain itself, and function codes, which are part of the contract's bytecode, the stack operates with limited space and is used for runtime operations only. It does not save transaction history; rather, it provides a mechanism for managing variable states as they are processed in real-time. This distinction is crucial for understanding how Solidity manages memory and efficiently performs computations, ensuring that local data needed for function execution is quickly accessible.