Comment 7 for bug 1065325

I just built QEMU from source (git master commit b6348f29, same gcc as you, MacOS 10.8.2), like this:
./configure --target-list=arm-softmmu && make -j2

and the resulting QEMU works for me. I tested with a Cortex-M3 image from here:
https://bugs.launchpad.net/qemu/+bug/1028260/+attachment/3233691/+files/stellaris-test.tar
If you untar that you'll find among other things a .bin file which is a system image for the lm3s6965evb board model, which you can run like this:
./arm-softmmu/qemu-system-arm -M lm3s6965evb -kernel ~/test-images/stellaris-test/qs_ek-lm3s6965.bin

So I think the chances are that it's just that you think that QEMU has hung because the particular guest image you're trying to run isn't working. Our M3 model has some known bugs so it's possible that it's running into one of them.

Other people also seem to have had trouble with FreeRTOS, see for instance bug 657006. Please can you try with an image that is known to work under QEMU, so that we can separate out whether this is a problem with our MacOS support or just that QEMU isn't emulating this board closely enough for the image you're trying to run?