Android emulate failed using AOSP source

Question

I downloaded Android full sources 5.1, 6.0, 7.0 and built them. I tried to check if the builds worked using the android emulator in the SDK, but they all failed except version 5.1. I replaced the original image files (system.img, ramdisk.img, and userdata.img) with newly built files, and then ran them. However, the Android logo never appeared, and the OS didn't boot. I chose mini-emulator-arm-debug and the original emulator image of the same version and AOSP.

I don't know why android 5.1 boots but android 6.0 and 7.0 don't. Has the method of executing the images in an emulator changed? Please help me.

1. Building from source succeeds in all three cases.
2. On execution, the emulator screen shows only black. I tried to connect using adb shell but failed.

Answer 1

Please try to run

lunch full-eng

and when finished, run the emulator.