macOS
All the tools can be installed using Homebrew or MacPorts:
Install tools with Homebrew
$ # GDB
$ brew install arm-none-eabi-gdb
$ # OpenOCD
$ brew install openocd
$ # QEMU
$ brew install qemu
NOTE If OpenOCD crashes you may need to install the latest version using:
$ brew install --HEAD openocd
Install tools with MacPorts
$ # GDB
$ sudo port install arm-none-eabi-gcc
$ # OpenOCD
$ sudo port install openocd
$ # QEMU
$ sudo port install qemu
That's all! Go to the next section.