d26c647f74
Prior to this change, all PRODUCT_* variables are inherited with list semantics, meaning the variable value in the current makefile as well as all the makefiles it inherits are concatenated together. Many of these variables are not lists, so this change adds the ability to classify a variable as a single-value variable, which will inherit at most one value (the first one), unless the variable is already defined in the current file. This change also marks all current variables as list variables. A future change will re-classify the single-value variables as such. Bug: 116769560 Test: presubmit Change-Id: I57719a5eefd0749e92c08b1773b6f929629267a3
Android Make Build System
This is the Makefile-based portion of the Android Build System.
For documentation on how to run a build, see Usage.txt
For a list of behavioral changes useful for Android.mk writers see Changes.md
For an outdated reference on Android.mk files, see build-system.html. Our Android.mk files look similar, but are entirely different from the Android.mk files used by the NDK build system. When searching for documentation elsewhere, ensure that it is for the platform build system -- most are not.
This Makefile-based system is in the process of being replaced with Soong, a new build system written in Go. During the transition, all of these makefiles are read by Kati, and generate a ninja file instead of being executed directly. That's combined with a ninja file read by Soong so that the build graph of the two systems can be combined and run as one.