Ask whether the separate compilation Android system without compiling HAL?

4.01 version has HAL. So file, but no source code.
Can download a new android 4.01 source code, then compile only Android system, skip the HAL section.

The new Android system and compile existing HAL. So files can be used together?

Please expert guidance<-! Main posts under Banner (D4) -><-! Posts under the main text (D5) ->
Reply:
4.0.1 can be directly compiled code will be out after replacing the following so you can make-snod generated.