gotos

Gotos are a control flow statement that transfers execution to a labeled location within the same program. The transfer is typically unconditional; the destination is a label defined elsewhere in the same function or subroutine. When executed, the program continues from that label as if code had jumped there.

Gotos have a long history in programming. They appear in languages such as C, C++, Fortran and BASIC, and in many older or lower-level languages. The concept was central to early languages when structured constructs were less rich. Dijkstra’s famous critique Goto considered harmful popularized caution about overusing them, though they remain in use in some low-level or performance-sensitive contexts.

Semantics vary by language, but common rules apply: the target label must exist in the same scope; in some languages, a goto cannot jump into the initialization of an automatic variable or across a block boundary. In languages with destructors or resource management, jumping over cleanup or object destruction can cause resource leaks or undefined behavior, so many style guides restrict or discourage their use.

Common uses include centralized error handling and cleanup code, where many exit points can jump to a single cleanup section. They are also used (with care) in implementing finite-state machines or highly optimized loops. Some languages provide more controlled alternatives, such as exceptions or structured loops, which reduce the need for gotos.

Overall, gotos are a low-level feature. When used sparingly and with clear intent, they can simplify certain patterns; when overused, they degrade readability and maintainability. Many modern coding standards therefore restrict them, recommending alternatives for ordinary control flow.