Building B2G OS with emulator-m option

Hi All,
I’ve followed https://github.com/kaiostech/gecko-b2g/blob/gonk/gonk.md to build B2G OS with emulator-m.But build.sh is failing with below error message:

"build/envsetup.sh: line 58: 4631 Segmentation fault (core dumped) make --no-print-directory -f build/core/config.mk dumpvar-TARGET_DEVICE

** Don’t have a product spec for: ‘full’
** Do you have the right repo manifest?

Build failed! <

Build with |./build.sh -j1| for better messages
If all else fails, use |rm -rf objdir-gecko| to clobber gecko and |rm -rf out| to clobber everything else."

./config.sh emulator-m : This executed successfully without any issue.

If anyone successfully build b2g OS with emulator-m option,please share the steps to build it.