Compilers

• Compilers


  Translate code into a form that can be executed, but do not execute the code
• Compiled code


  Executable code in a form that cannot be read by a human or readily reverse-engineered
• Most commercial software applications are distributed as compiled code so that the source code is protected. This is advantageous for commercial developers who make money from their code.
• Compiler


  1. Takes the source code as its set of instructions

  2. Puts the source code through a series of processes to produce executable code
• Stages of compilation


  • Lexical analysis
  • Syntax analysis
  • Semantic analysis
  • Code generation
  • Optimisation
• A disadvantage of compilation is that any compilation errors are reported at the end of the compilation process. This is a disadvantage for large programs, as errors may be interlinked.
• If any errors are found, the program will need to be rectified and then compiled again; this process is repeated until the program is free from errors
• When the program has successfully compiled, the executable file will not need to be translated again (unless the source code is changed)
• Advantage of compiled code

  Faster running times, as no further translation is required
• Advantage of using a compiler

  The user does not need a translator (i.e. interpreter) to be installed on their computer