Cibyl is a programming environment that allows compiled C/C++ programs to execute on J2ME-capable phones. GPL

Cibyl 19
Cibyl uses GCC to compile programs to MIPS binaries, and these are then translated into Java bytecode. The use of binary translation and the simplicity of translating MIPS instructions means that Cibyl programs can be quite well-performing. With Cibyl, programs written in C/C++ can be ported to J2ME without switching languages.

C++-based toolkit for GUI development. LGPL

FOX 1.6.28 includes a rich set of widgets and has powerful yet simple layout managers, MDI widgets, and mega-widgets. FOX incorporates support for XDND for drag and drop, X clipboard and X Selection, watching other I/O channels and sockets, timers and idle processing, object serialization and deserialization, a registry to save persistent settings, and 3D widgets using Mesa or OpenGL. FOX works on Linux, IRIX, Solaris, HP/UX, AIX, Tru64 Unix, Windows 9x,NT,2K (VC++, GNUWIN32, Borland, VisualAge C++), FreeBSD, and Sequent.

C++ image processing library. GPL

ExactImage 0.3.5 is a fast C++ image processing library. Unlike ImageMagick, it allows operation in several color spaces and bit depths natively, resulting in much lower memory and computational requirements. Some optimized algorithms operate in 1/20 of the time ImageMagick requires, and displaying large images can be as fast as 1/10 of the time the "display" program takes.

Integrated Development Environment (IDE) for C and C++ in GNU/Linux. GPL

Anjuta IDE 2.1.2 is a versatile Integrated Development Environment (IDE) for C and C++ in GNU/Linux. It has been written for GTK/GNOME, and features a number of advanced programming facilities. These include project management, application wizards, an onboard interactive debugger, and a powerful source editor with source browsing and syntax highlighting.

C++ library that converts many facilities that are found in the standard C library into a form that is more appropriate for use in a C++ context. LGPL

WxLib 0.32 is a widely resuable C++ library that converts many facilities that are found in the standard C library into a form that is more appropriate for use in a C++ context. The library wraps functions for dealing with threads, files, FIFOs, serial I/O, sockets, and directories. It focuses on the correct use of C++ functions, and especially on the correct use of error handling mechanisms.

C++-based toolkit for GUI development. LGPL

FOX 1.7.8 is a C++-based toolkit for GUI development. It includes a rich set of widgets and has powerful yet simple layout managers, MDI widgets, and mega-widgets. FOX incorporates support for XDND for drag and drop, X clipboard and X Selection, watching other I/O channels and sockets, timers and idle processing, object serialization and deserialization, a registry to save persistent settings, and 3D widgets using Mesa or OpenGL. FOX works on Linux, IRIX, Solaris, HP/UX, AIX, Tru64 Unix, Windows 9x,NT,2K (VC++, GNUWIN32, Borland, VisualAge C++), FreeBSD, and Sequent.

C++ class library for developing cross-platform systems software for POSIX and Windows systems. LGPL

commonc++ 0.3 is a C++ class library for developing cross-platform systems software for POSIX and Windows systems. It provides an intuitive, object-oriented abstraction and portability layer around common operating system facilities like threads, concurrency mechanisms, sockets, networking, shared memory and other IPC mechanisms, regular expressions, files, streams, logging, process execution, scheduling, and more. It also includes a collection of common abstractions like strings, buffers, and object pools.