5128702ed3
llvm-ar is required for platform LTO build. With GNU ar, we used crsPD flags, however 'P' flag is not supported by llvm-ar. Since none of the platform archive files are built using third party AR, the 'P' flag should not matter to us. However we've been relying on one side-effect of 'P', where 'ar foo.a some/path/to/obj.o' when foo.a already has a file named 'obj.o' will be an append operation, regardless whether the existing one is the same (ar has no way of telling the difference). We workaround this by always appending ('q' flag) for llvm-ar. This may result in larger intermediate archive files (more duplication) but will not affect the final build result. Bug: 71618641 Test: m checkbuild Change-Id: Id96a244cfe49cecfba08cc868dd18934ecb4ff23 |
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core | ||
target | ||
tests | ||
tools | ||
.gitignore | ||
Android.mk | ||
Changes.md | ||
CleanSpec.mk | ||
OWNERS | ||
README.md | ||
Usage.txt | ||
buildspec.mk.default | ||
envsetup.sh | ||
help.sh | ||
navbar.md | ||
tapasHelp.sh |
README.md
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For an outdated reference on Android.mk files, see build-system.html.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.