Solidity is the most mainstream language for Ethereum smart contracts, but it has many issues, some of which stem from design flaws in the language itself, while others are related to the features of the Ethereum Virtual Machine (EVM). Below is an in-depth analysis of the main issues with Solidity:
1. Language design flaws
1. Many security issues
Solidity has frequent security vulnerabilities, for example:
Reentrancy attack
Integer overflow/underflow (although SafeMath and built-in protections after 0.8 exist)
Uninitialized variables may point to incorrect addresses
Abuse of delegatecall can easily lead to contract logic being tampered with
The language does not enforce security best practices, so developers must 'remember how to write' securely.
2. High complexity, prone to errors
The syntax of Solidity resembles JavaScript, but its underlying semantics are closer to low-level assembly or C language, making it easy for developers to misunderstand its behavior.
For example, the variable allocation methods of storage vs memory are easy to misuse, leading to unpredictable results.
3. Error messages are unclear
The compiler error messages and debugging information are poor, especially when debugging gas consumption and low-level calls (such as call, delegatecall, staticcall) is fraught with difficulties.
4. Non-unified interfaces, poor code readability
There are significant differences in syntax and behavior between different versions, such as:
Frequent changes from Solidity 0.4 to 0.8
Many projects cannot upgrade uniformly, resulting in ecological chaos
2. Problems arising from EVM limitations
1. Code abnormalities caused by gas optimization
Due to high execution costs, many developers write 'unreadable' extremely optimized code to save gas, sacrificing maintainability and security.
2. The EVM is not designed for efficient execution
The EVM is a stack-based virtual machine, which is inefficient and difficult to debug.
The EVM lacks native support for data structures, such as hash tables and sets, which need to be implemented manually.
3. Ecosystem and toolchain issues
1. Serious ecological fragmentation
Tools like Truffle, Hardhat, Foundry, and Brownie operate independently, with varying support for Solidity across different frameworks, making it difficult to unify.
2. Lack of support for static analysis tools for developers
Compared to modern languages (like Rust, TypeScript), Solidity's type system is weak and lacks powerful static analysis tools.
Although there are tools like Slither and MythX, the learning curve is high and the false positive rate is also high.
4. Conflicts with future development trends
1. Difficult to support formal verification
The syntax and semantics of Solidity are not conducive to mathematical formal verification, showing clear disadvantages compared to Move and Vyper.
2. The contract upgrade mechanism is unfriendly
Solidity does not natively support modularity or hot updates, requiring developers to manually implement the proxy pattern, which is easy to get wrong.
3. Not developer-friendly
Although Web3 encourages broad participation, the barriers to entry for Solidity development remain high, making it unsuitable for non-technical individuals or beginners to start directly.
