“device/htc/ace/ace.mk” does not exist. Stop. Cyanogenmod

Assuming you get this error here is an easy fix.

Goto /yourcmdir/vendor/cyanogen/products and edit AndroidProducts.mk. It should look something like this

PRODUCT_MAKEFILES := \
$(LOCAL_DIR)/cyanogen_ace.mk \
…

Remove all the device .mk you don’t need and keep only the one you are compiling and already have the device tree.

Then

. build/envsetup.sh

lunch

make -j4

Et voila!