GNUstep Objective-C Runtime 1.5 =============================== This is the fifth official release of the GNUstep Objective-C runtime (a.k.a. libobjc2). This runtime was designed to support the features of Objective-C 2 for use with GNUstep and other Objective-C programs. Highlights of this release include: - Support for Apple-compatible garbage collection APIs, along with extensions to support CoreFoundation-style explicit reference counting in a garbage collected environment. This uses the Boehm garbage collector and is enabled by default. To build without garbage collection specify the boehm_gc=no option when building. - The runtime will now use Boehm GC for several internal data structures, if it is built with GC enabled. This avoids the need for defensive programming with respect to thread safety in several places. - This is the first release to provide a superset of the functionality provided by the Mac Objective-C runtime, as shipped with OS X 10.6. - Full support for Automatic Reference Counting (ARC), compatible with OS X 10.7 and iOS 5. - The LLVM optimisation passes have been improved and better tested. Code compiled with them now passes the EtoileFoundation test suite. You may obtain the code for this release from subversion at the following subversion branch: svn://svn.gna.org/svn/gnustep/libs/libobjc2/1.4 Alternatively, a tarball is available from: http://download.gna.org/gnustep/libobjc2-1.4.tar.bz2 The runtime library is responsible for implementing the core features of the object model, as well as exposing introspection features to the user. The GNUstep runtime implements Apple's Objective-C Runtime APIs, and a small number of GCC APIs for legacy compatibility. This library is based on the Étoilé Objective-C Runtime, an earlier research prototype, and includes support for non-fragile instance variables, type-dependent dispatch, and object planes. It is fully compatible with the FSF's GCC Objective-C ABI and also implements a new ABI that is supported by Clang and Étoilé's LanguageKit and is required for some of the newer features. Although the runtime has been tested by several people, and is being used extensively by the Étoilé project, it is entirely new (MIT licensed) code and may still contain bugs. If you come across any problems, please report them to the GNUstep Developer mailing list .