master: qemu-native fails do_compile: unrecognized command line option Œ-fstack-protector-strong¹

I'm seeing the following error attempting to build qemu-native for qemux86-64 from the master branch:

ERROR: Logfile of failure stored in:
/build/yocto/master/intel-corei7-64_20141008094748/build/tmp/work/x86_64-l i
nux/qemu-native/2.1.0-r0/temp/log.do_compile.737
Log data follows:

| DEBUG: Executing shell function do_compile
| NOTE: make -j 1
|   GEN   arm-linux-user/config-devices.mak
|   GEN   arm-softmmu/config-devices.mak
|   GEN   i386-linux-user/config-devices.mak
|   GEN   i386-softmmu/config-devices.mak
|   GEN   x86_64-linux-user/config-devices.mak
|   GEN   x86_64-softmmu/config-devices.mak
|   GEN   config-all-devices.mak
|   GEN   config-host.h
|   GEN   qemu-options.def
|   GEN   qmp-commands.h
|   GEN   qapi-types.h
|   GEN   qapi-visit.h
|   GEN   qapi-event.h
|   GEN   trace/generated-events.h
|   GEN   trace/generated-tracers.h
|   GEN   tests/test-qapi-types.h
|   GEN   tests/test-qapi-visit.h
|   GEN   tests/test-qmp-commands.h
|   GEN   tests/test-qapi-event.h
|   CC    tests/qemu-iotests/socket_scm_helper.o
|   LINK  tests/qemu-iotests/socket_scm_helper
| g++: error: unrecognized command line option '-fstack-protector-strong'
| 

/build/yocto/master/intel-corei7-64_20141008094748/build/tmp/work/x86_64-l i
nux/qemu-native/2.1.0-r0/qemu-2.1.0/rules.mak:88: recipe for target 'tests/qemu-iotests/socket_scm_helper' failed

| make: *** [tests/qemu-iotests/socket_scm_helper] Error 1
| ERROR: oe_runmake failed
| WARNING: exit code 1 from a shell command.
| ERROR: Function failed: do_compile (log file is located at

/build/yocto/master/intel-corei7-64_20141008094748/build/tmp/work/x86_64-l i
nux/qemu-native/2.1.0-r0/temp/log.do_compile.737)
ERROR: Task 7 (virtual:native:/build/yocto/master/intel-corei7-64_20141008094748/poky/me t
a/recipes-devtools/qemu/qemu_2.1.0.bb, do_compile) failed with exit code '1'

The key bit being:
| g++: error: unrecognized command line option '-fstack-protector-strong'

As this appears to be a toolchain versioning issue, I tested this independently:

dvhart@rage:~

$ g++-4.8 -fstack-protector-strong test.c -o test
g++-4.8: error: unrecognized command line option
Œ-fstack-protector-strong¹

dvhart@rage:~

$ g++-4.9 -fstack-protector-strong test.c -o test
dvhart@rage:~

$ ./test
Hello World!

Sure enough, 4.9 supports this, and 4.8 does not. I'm looking into if this
is a qemu-native configuration issue or something else... But if anyone already has a solution in hand, please let me know.