Compiler

This article is about software to translate computer languages. For the manga, see Compiler (manga).
"Compile" and "Compiling" redirect here. For the software company, see Compile (company). For other uses, see Compilation.

Program execution
General concepts
Types of code
Compilation strategies
Notable runtimes
Notable compilers & toolchains

In computing, a compiler is a computer program that translates computer code written in one programming language (the source language) into another language (the target language). The name "compiler" is primarily used for programs that translate source code from a high-level programming language to a low-level programming language (e.g. assembly language, object code, or machine code) to create an executable program.[1][2]: p1 [3]

There are many different types of compilers which produce output in different useful forms. A cross-compiler produces code for a different CPU or operating system than the one on which the cross-compiler itself runs. A bootstrap compiler is often a temporary compiler, used for compiling a more permanent or better optimised compiler for a language.

Related software include decompilers, programs that translate from low-level languages to higher level ones; programs that translate between high-level languages, usually called source-to-source compilers or transpilers; language rewriters, usually programs that translate the form of expressions without a change of language; and compiler-compilers, compilers that produce compilers (or parts of them), often in a generic and reusable way so as to be able to produce many differing compilers.

A compiler is likely to perform some or all of the following operations, often called phases: preprocessing, lexical analysis, parsing, semantic analysis (syntax-directed translation), conversion of input programs to an intermediate representation, code optimization and machine specific code generation. Compilers generally implement these phases as modular components, promoting efficient design and correctness of transformations of source input to target output. Program faults caused by incorrect compiler behavior can be very difficult to track down and work around; therefore, compiler implementers invest significant effort to ensure compiler correctness.[4]

Compilers are not the only language processor used to transform source programs. An interpreter is computer software that transforms and then executes the indicated operations.[2]: p2  The translation process influences the design of computer languages, which leads to a preference of compilation or interpretation. In theory, a programming language can have both a compiler and an interpreter. In practice, programming languages tend to be associated with just one (a compiler or an interpreter).

  1. ^ "Encyclopedia: Definition of Compiler". PCMag.com. Retrieved 2 July 2022.
  2. ^ a b Compilers: Principles, Techniques, and Tools by Alfred V. Aho, Ravi Sethi, Jeffrey D. Ullman - Second Edition, 2007
  3. ^ Sudarsanam, Ashok; Malik, Sharad; Fujita, Masahiro (2002). "A Retargetable Compilation Methodology for Embedded Digital Signal Processors Using a Machine-Dependent Code Optimization Library". Readings in Hardware/Software Co-Design. Elsevier. pp. 506–515. doi:10.1016/b978-155860702-6/50045-4. ISBN 9781558607026. A compiler is a computer program that translates a program written in a high-level language (HLL), such as C, into an equivalent assembly language program [2].
  4. ^ Sun, Chengnian; Le, Vu; Zhang, Qirun; Su, Zhendong (2016). "Toward understanding compiler bugs in GCC and LLVM". Proceedings of the 25th International Symposium on Software Testing and Analysis. ISSTA 2016. ACM. pp. 294–305. doi:10.1145/2931037.2931074. ISBN 9781450343909. S2CID 8339241.