Fixing “Cannot display lunch menu” in AOSP 15 (Android 15)

Problem

When setting up AOSP 15 and running lunch, you might see:

You're building on Linux

Warning: Cannot display lunch menu.

Note: You can invoke lunch with an explicit target:

This happens because AOSP 15 uses the Soong build system, which no longer auto-populates the interactive lunch menu unless a build variable cache is generated.

Solution: Run build_build_var_cache

To restore the full lunch menu, run:

build_build_var_cache

Then try lunch again:

lunch

You should now see a complete list of targets like:

Lunch menu .. Here are the common combinations:
  1. aosp_cf_x86_64_phone-trunk_staging-userdebug
  2. aosp_arm64-trunk_staging-userdebug
  3. aosp_raven-trunk_staging-userdebug
  ...