Building Android (lunch oddities)


#1

Something of an Android-building noob here, so my apologies if this is basic stuff, but I have to start somewhere and googling didn’t help.

I get the following environment during the build process (using the Mac guidelines as per https://source.android.com/source/devices). Shouldn’t the target cpu variant be cortex-a73? Or are all 64-bit ARM processors referred to as cortex-a53 in this build system? I was also surprised by the TARGET_ARCH_VARIANTS (one armv7-a-neon and one armv8-a sans neon).

$ lunch hikey960-userdebug

============================================
PLATFORM_VERSION_CODENAME=O
PLATFORM_VERSION=O
TARGET_PRODUCT=hikey960
TARGET_BUILD_VARIANT=userdebug
TARGET_BUILD_TYPE=release
TARGET_PLATFORM_VERSION=OPR1
TARGET_BUILD_APPS=
TARGET_ARCH=arm64
TARGET_ARCH_VARIANT=armv8-a
TARGET_CPU_VARIANT=cortex-a53
TARGET_2ND_ARCH=arm
TARGET_2ND_ARCH_VARIANT=armv7-a-neon
TARGET_2ND_CPU_VARIANT=cortex-a53
HOST_ARCH=x86_64
HOST_2ND_ARCH=x86
HOST_OS=darwin
HOST_OS_EXTRA=Darwin-16.5.0-x86_64-i386-64bit
HOST_CROSS_OS=
HOST_CROSS_ARCH=
HOST_CROSS_2ND_ARCH=
HOST_BUILD_TYPE=release
BUILD_ID=NYC
OUT_DIR=out
AUX_OS_VARIANT_LIST=


#2

cortex a53 because of the lowest type of cpu afaik a73 is just boosted up 53 with more IPC but the same instruction set, again afaik could be wrong but it mostly should be because of backwards compatibility for the a53

armv7-a-neon for 32bit support
armv8-a default arm64 arch for both 53 and 73


#3

it shows correctly now on the latest source:

============================================
PLATFORM_VERSION_CODENAME=O
PLATFORM_VERSION=O
TARGET_PRODUCT=hikey960
TARGET_BUILD_VARIANT=userdebug
TARGET_BUILD_TYPE=release
TARGET_PLATFORM_VERSION=OPR1
TARGET_BUILD_APPS=
TARGET_ARCH=arm64
TARGET_ARCH_VARIANT=armv8-a
TARGET_CPU_VARIANT=cortex-a73
TARGET_2ND_ARCH=arm
TARGET_2ND_ARCH_VARIANT=armv7-a-neon
TARGET_2ND_CPU_VARIANT=cortex-a73
HOST_ARCH=x86_64
HOST_2ND_ARCH=x86
HOST_OS=linux
HOST_OS_EXTRA=Linux-4.8.0-58-generic-x86_64-with-Ubuntu-16.04-xenial
HOST_CROSS_OS=windows
HOST_CROSS_ARCH=x86
HOST_CROSS_2ND_ARCH=x86_64
HOST_BUILD_TYPE=release
BUILD_ID=NYC
OUT_DIR=out
AUX_OS_VARIANT_LIST=
============================================