.. _top:

Introduction
============

.. index:: introduction

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
|package_version|
version |gcc_version|.  The use of the GNU compilers is documented in a
separate manual.  See :ref:`gcc:top`.

This manual is mainly a reference manual rather than a tutorial.  It
discusses how to contribute to GCC (see :ref:`contributing`), the
characteristics of the machines supported by GCC as hosts and targets
(see :ref:`portability`), how GCC relates to the ABIs on such systems
(see :ref:`interface`), and the characteristics of the languages for
which GCC front ends are written (see :ref:`languages`).  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
https://gcc.gnu.org/readings.html.