Easy to use fast C API for creating charts and graphs

http://www.fred.net/brv/chart/

Graphic library for GTK+

https://developer.gnome.org/gdk-pixbuf/

Gnome DOM Engine

http://gdome2.cs.unibo.it/

Fast and lightweight GTK+ IDE

https://www.geany.org/

Graph based image processing framework

http://gegl.org/

Gtk+ based, file manager inspired by DirectoryOpus

http://www.obsession.se/gentoo/

D-Bus service that provides location information

https://gitlab.freedesktop.org/geoclue/geoclue/wikis/home

Convenience library for the geocoding and reverse geocoding

https://git.gnome.org/browse/geocode-glib

getopt(1) replacement that supports GNU-style long options

https://software.frodo.looijaard.name/getopt/

GNU gettext meta package

https://www.gnu.org/software/gettext/

Check the validity and consistency of PO and POT files

https://gettext-lint.sourceforge.net/

Alter gettext po files in special ways

https://src.fedoraproject.org/rpms/gettext/blob/master/f/msghack.py

GNU gettext runtime libraries and programs

https://www.gnu.org/software/gettext/

GNU gettext development and translation tools

https://www.gnu.org/software/gettext/

The GGZ Gaming Zone - Core Client Libraries

http://www.ggzgamingzone.org/

Ghostscript 8.x PostScript interpreter

http://www.cs.wisc.edu/~ghost/doc/GPL/index.htm

Ghostscript 8.x PostScript interpreter

http://www.cs.wisc.edu/~ghost/doc/GPL/index.htm

A utility library that includes a wrapper for imlib2

http://www.linuxbrit.co.uk/giblib/

Tools and library routines for working with GIF images

https://sourceforge.net/projects/giflib/

Manipulates GIF images and animations

https://www.lcdf.org/gifsicle/

Distributed source code management tool (lite flavor)

https://git-scm.com/

GitHub Enterprise Backup Utilities

https://github.com/github/backup-utils

GNOME Javascript binding

http://live.gnome.org/Gjs

User interface builder for GTK+/GNOME

http://glade.gnome.org/

OpenGL spinning pocket watch demo and benchmark utility

GL Tubing and Extrusion Library

https://linas.org/gle/

OpenGL Extension Wrangler Library

https://glew.sourceforge.net/

Network-related giomodules for glib

Some useful routines of C programming (previous stable version)

http://www.gtk.org/

Some useful routines of C programming (current stable version)

https://www.gtk.org/

Programming reference for devel/glib20

https://www.gtk.org/

C++ interfaces for glib2

https://www.gtkmm.org/

OpenGL image compositing library

http://freedesktop.org/Software/glitz

GLX extension headers

http://www.freedesktop.org/wiki/Software/xlibs

GNU version of 'make' utility

https://www.gnu.org/software/make/

Minimalist version of gnu make

http://www.gnu.org/software/make/make.html

Well-known mastermind game

http://gap.nongnu.org/gmastermind/

Library (written in C) for parsing and creating messages using MIME

http://spruce.sourceforge.net/gmime/

Library (written in C) for parsing and creating messages using MIME

http://spruce.sourceforge.net/gmime/

Library (written in C) for parsing and creating messages using MIME

https://spruce.sourceforge.net/gmime/

Well-known minesweeper game for GNUstep

https://gap.nongnu.org/gmines/

Generic matrix template library

https://getfem.org/gmm/

Free library for arbitrary precision arithmetic

https://gmplib.org/

GNATS, the GNU Problem Report Management System

https://www.gnu.org/software/gnats/

Simple network library built upon Glib-2

https://www.gnetlibrary.org/

Sound files for use with GNOME 2

Collection of backgrounds for GNOME

Common automake macros for GNOME 3

https://www.gnome.org/

Programming reference for x11/gnome-desktop

http://www.gnome.org/

GNOME 3 dictionary lookup application

https://wiki.gnome.org/Dictionary