A compiler reads source code, checks language rules and transforms the program into a target representation such as machine code, bytecode or another language. Intermediate representations allow separate analysis and optimization stages.
Compiler correctness matters because a translation error can affect every program built through it. AI can assist with implementation or optimization, but benchmark improvements and successful examples cannot substitute for semantic checks and broad compatibility evidence.
ELI5
A compiler is a translator for computer programs. It takes instructions written in one form and turns them into a form another system can use.
For example, a compiler can turn a short program written by a person into instructions a processor can run. The translated program should calculate the same answer as the original.
Does a compiler always produce machine code?
No. Its output can also be bytecode, an intermediate representation or source code in another language.
Why is compiler testing especially important?
A single translation defect can introduce incorrect behavior into many otherwise valid programs.
