For embedded firmware engineers that develop in Linux or Windows build environments and cross-compile code for ARM targets, Mentor Graphic's Sourcery GCC toolchains are hard to beat. Until now, engineers using Macs were out-of-luck.
The good news is that for several years we have built Mac OS X cross toolchains for internal use based on Mentor Graphic's robust source tarballs. In the very near future we will be making our internal tool builds available to the general development community from our website. Moving forward these builds will reasonably align with Mentor Graphic's native releases for ARM EABI and GNU/Linux targets.