GNU C Language Extensions

This part of the documentation is a modified version of the C Extensions section of the GCC Manual. Therefore it is licensed under the GNU Free Documentation License.

TIGCC (like all GNU C compilers) provides several language features not found in ISO standard C. To test for the availability of these features in conditional compilation, check for a predefined macro __GNUC__, which is always defined under GCC.

Some features that are in ISO C99 but not C89 are also, as extensions, accepted by GCC in C89 mode.

Original author: Free Software Foundation, Inc.
Authors of the modifications: Zeljko Juric, Sebastian Reichelt, and Kevin Kofler
Published by the TIGCC Team.
See the History section for details and copyright information.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with the Invariant Sections being "GNU General Public License" and "Funding Free Software", the Front-Cover texts being (a) (see below), and with the Back-Cover Texts being (b) (see below). A copy of the license is included in the section entitled "GNU Free Documentation License".

(a) The FSF's Front-Cover Text is:

A GNU Manual

(b) The FSF's Back-Cover Text is:

You have freedom to copy and modify this GNU Manual, like GNU software. Copies published by the Free Software Foundation raise funds for GNU development.