Linker (computing)
= Linker (computing)
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A <linker (computing)> is a program that combines compiled or assembled components and connects references to their definitions. It reads <object files> and libraries, resolves named symbols, and applies <relocation (computing)> when locations become known. A typical output is an executable program or a shared <software library>.<Overview in the GNU ld documentation>[§1 Overview: object/archive inputs, relocation and symbol references]{ref}
Suppose one source file calls `square` and another defines it. Their <object files> can be produced separately; the <linker (computing)> matches the call's unresolved symbol to the definition and arranges the final reference. A missing definition can therefore cause a link-time failure even when each source file compiled successfully. Some references can instead be resolved when a shared <software library> is loaded.