This file documents the internals of the GNU compilers.

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A GNU Manual

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Short Table of Contents

Table of Contents


This manual documents the internals of the GNU compilers, including how to port them to new targets and some information about how to write front ends for new languages. It corresponds to the compilers (GCC) version 14.0.1. The use of the GNU compilers is documented in a separate manual. See Introduction in Using the GNU Compiler Collection (GCC).

This manual is mainly a reference manual rather than a tutorial. It discusses how to contribute to GCC (see Contributing to GCC Development), the characteristics of the machines supported by GCC as hosts and targets (see GCC and Portability), how GCC relates to the ABIs on such systems (see Interfacing to GCC Output), and the characteristics of the languages for which GCC front ends are written (see Language Front Ends in GCC). It then describes the GCC source tree structure and build system, some of the interfaces to GCC front ends, and how support for a target system is implemented in GCC.

Additional tutorial information is linked to from