android 系统编译要求，官方资料

Selectingakernel

device/<vendor>/<name>

$gitclonehttps://android.googlesource.com/kernel/hikey-linaro$cdhikey-linaro
$gitlog--max-count=1kernel

Identifyingkernelversion

$ddif=kernelbs=1skip=$(LC_ALL=Cgrep-a-b-o$'\x1f\x8b\x08\x00\x00\x00\x00\x00'kernel|cut-d':'-f1)|zgrep-a'Linuxversion'

$ddif=zImage-dtbbs=1skip=$(LC_ALL=Cod-Ad-x-w2zImage-dtb|grep8b1f|cut-d''-f1|head-1)|zgrep-a'Linuxversion'

Downloadingsources

gitclone

$gitclonehttps://android.googlesource.com/kernel/common.git$gitclonehttps://android.googlesource.com/kernel/hikey-linaro$gitclonehttps://android.googlesource.com/kernel/x86_64.git$gitclonehttps://android.googlesource.com/kernel/exynos.git$gitclonehttps://android.googlesource.com/kernel/goldfish.git$gitclonehttps://android.googlesource.com/kernel/msm.git$gitclonehttps://android.googlesource.com/kernel/omap.git$gitclonehttps://android.googlesource.com/kernel/samsung.git$gitclonehttps://android.googlesource.com/kernel/tegra.git

goldfish

msm

omap

samsung

tegra

exynos

x86_64

hikey-linaro

Downloadingaprebuiltgcc

$exportPATH=$(pwd)/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6/bin:$PATH

$exportPATH=$(pwd)/prebuilts/gcc/darwin-x86/arm/arm-eabi-4.6/bin:$PATH

$gitclone'target='_blank'>https://android.googlesource.com/platform/prebuilts/gcc/linux-x86/arm/arm-eabi-4.6[/code]

Buildingthekernel
Whenyouknowthelastcommitmessageforakernelandhavesuccessfullydownloadedthekernelsourceandprebuiltgcc,youarereadytobuildthekernel.Thefollowingbuildcommandsusethehikeykernel:
$exportARCH=arm64
$exportCROSS_COMPILE=aarch64-linux-android-
$cdhikey-linaro
$gitcheckout-bandroid-hikey-linaro-4.1origin/android-hikey-linaro-4.1
$makehikey_defconfig
$make

Tobuildadifferentkernel,simplyreplace
hikey-linaro
withthenameofthekernelyouwanttobuild.
Theimageoutputstothe
arch/arm64/boot/Image
directory;thekernelbinaryoutputstothe
arch/arm64/boot/dts/hisilicon/hi6220-hikey.dtb
fle.
Copythe
Image
directoryandthe
hi6220-hikey.dtb
filetothe
hikey-kernel
directory.
Alternatively,youcanincludethe
TARGET_PREBUILT_KERNEL
variablewhileusing
make
bootimage
(oranyother
make
commandlinethatbuildsabootimage).Thisvariableissupportedbyalldevicesasitissetupvia
device/common/populate-new-device.sh
.
Forexample:
$exportTARGET_PREBUILT_KERNEL=$your_kernel_path/arch/arm/boot/zImage-dtb


Note:Kernelnamesdifferbydevice.Tolocatethecorrectfilenameforyourkernel,referto
device/<vendor>/<name>
inthekernelsource.


KnownIssues

INTHISDOCUMENT
Buildissues

Missing
CellBroadcastReceiverintorobuilds
Missing
CTSNativeXMLGenerator
BlackGingerbread
Emulator
Emulator
builtonMacOS10.7Liondoesn'twork.
WITH_DEXPREOPT=true
and
emulatorbuilds.
"Permission
Denied"duringbuilds.
Build
errorsrelatedtousingthewrongcompiler.
Build
errorscausedbynon-defaulttoolsettings.
Build
errorwith4.0.xandearlieronMacOS10.7.
Build
erroronMacOSwithXCode4.3.
Build
errorwith4.0.xandearlieronUbuntu11.10.

Sourcesyncissues


Difficulties
syncingthesourcecode(proxyissues).
Difficulties
syncingthesourcetree(VirtualBoxEthernetissues).
Difficulties
syncingthesourcetree(DNSissues).
Difficulties
syncingthesourcetree(TCPissues).

Runtimeissues

Camera
andGPSdon'tworkonGalaxyNexus.

Evenwithourbestcare,smallproblemssometimesslipin.ThispagekeepstrackoftheknownissuesaroundusingtheAndroidsourcecode.

Buildissues

MissingCellBroadcastReceiverintorobuilds
Symptom
OnAOSPbuildsfortoro(uptoJellyBean4.2.1),CellBroadcastReceiverdoesn'tgetincludedinthesystem.

Cause:
There'satypoin
vendor/samsung/toro/device-partial.mk
,where
PRODUCT_PACKAGES
hastheKreplacedbyanH.
Fix:Usethelatestpackagesfor4.2.2,ormanuallyfixthetypo.

MissingCTSNativeXMLGenerator
Symptom:OnsomebuildsofIceCreamSandwichandlater,thefollowingwarningisprintedearlyduringthebuild:
/bin/bash:line
0:cd:cts/tools/cts-native-xml-generator/src/res:Nosuchfileordirectory

Cause:Somemakefilereferencesthatpath,whichdoesn'texist.
Fix:None.Thisisaharmlesswarning.

BlackGingerbreadEmulator
Symptom:Theemulatorbuiltdirectlyfromthegingerbreadbranchdoesn'tstartandstaysstuckonablackscreen.
Cause:ThegingerbreadbranchusesversionR7oftheemulator,whichdoesn'thaveallthefeaturesnecessarytorunrecentversionsofgingerbread.
Fix:UseversionR12oftheemulator,andanewerkernelthatmatchesthosetools.Noneedtodoacleanbuild.
$repoforallplatform/external/qemu-cgitcheckoutaosp/tools_r12
$make
$emulator-kernelprebuilt/android-arm/kernel/kernel-qemu-armv7


EmulatorbuiltonMacOS10.7Liondoesn'twork.
Symptom:Theemulator(anyversion)builtonMacOS10.7Lionand/oronXCode4.xdoesn'tstart.
Cause:Somechangeinthedevelopmentenvironmentcausestheemulatortobecompiledinawaythatpreventsitfromworking.
Fix:UseanemulatorbinaryfromtheSDK,whichisbuiltonMacOS10.6withXCode3andworksonMacOS10.7.

WITH_DEXPREOPT=true
andemulatorbuilds.
Symptom:Whenconductingpartialbuildsorsyncs(makesystemnodependencies)onemulatorbuilds,theresultingbuilddoesn'twork.
Cause:AllemulatorbuildsnowrunDexoptimizationatbuildtimebydefault,whichrequirestofollowalldependenciestore-optimizetheapplicationseachtimetheframeworkchanges.
Fix:LocallydisableDexoptimizationswith
exportWITH_DEXPREOPT=false
,deletetheexistingoptimizedversionswith
make
installclean
andrunafullbuildtore-generatenon-optimizedversions.Afterthat,partialbuildswillwork.

"PermissionDenied"duringbuilds.
Symptom:Allbuildsfailwith"PermissionDenied",possiblyalongwithanti-viruswarnings.
Cause:Someanti-virusprogramsmistakenlyrecognizesomesourcefilesintheAndroidsourcetreeasiftheycontainedviruses.
Fix:Afterverifyingthattherearenoactualvirusesinvolved,disableanti-virusontheAndroidtree.Thishastheaddedbenefitofreducingbuildtimes.

Builderrorsrelatedtousingthewrongcompiler.
Symptom:Thebuildfailswithvarioussymptoms.Onesuchsymptomis
cc1:error:unrecognizedcommandlineoption"-m32"

Cause:TheAndroidbuildsystemusesthedefaultcompilerinthePATH,assumingit'sasuitablecompilertogeneratebinariesthatrunonthehost.Othersituations(e.g.usingtheAndroidNDKor
buildingthekernel)causethedefaultcompilertonotbeahostcompiler.
Fix:Usea"clean"shell,inwhichnopreviousactionscouldhaveswappedthedefaultcompiler.

Builderrorscausedbynon-defaulttoolsettings.
Symptom:Thebuildfailswithvarioussymptoms,possiblycomplainingaboutmissingfilesorfilesthathavethewrongformat.Onesuchsymptomis
member
[...]inarchiveisnotanobject
.
Cause:TheAndroidbuildsystemtendstousemanyhosttoolsandtorelyontheirdefaultbehaviors.Somesettingschangethosetools'behaviorsandmakethembehaveinwaysthatconfusethebuild
system.Variablesknowntocausesuchissuesare
CDPATH
and
GREP_OPTIONS
.
Fix:BuildAndroidinanenvironmentthathasasfewcustomizationsaspossible.

Builderrorwith4.0.xandearlieronMacOS10.7.
Symptom:BuildingIceCreamSandwich4.0.x(andolderversions)failsonMacOS10.7witherrorssimilartothis:
Undefinedsymbols
forarchitecturei386:"_SDL_Init"

Cause:4.0.xisnotcompatiblewithMacOS10.7.
Fix:EitherdowngradetoMacOS10.6,orusethemasterbranch,whichcanbebuiltonMacOS10.7.
$repoinit-bmaster
$reposync


BuilderroronMacOSwithXCode4.3.
Symptom:AllbuildsfailwhenusingXCode4.3.
Cause:XCode4.3switchedthedefaultcompilerfromgcctollvm,andllvmrejectscodethatusedtobeacceptedbygcc.
Fix:UseXCode4.2.

Builderrorwith4.0.xandearlieronUbuntu11.10.
Symptom:BuildingIceCreamSandwich4.0.x(andolderversions)onUbuntu11.10andnewerfailswitherrorssimilartothis:
<command-line>:0:0:
warning:"_FORTIFY_SOURCE"redefined[enabledbydefault]

Cause:Ubuntu11.10usesaversionofgccwherethatsymbolisdefinedbydefault,andAndroidalsodefinesthatsymbol,whichcausesaconflict.
Fix:EitherdowngradetoUbuntu10.04,orusethemasterbranch,whichcanbecompiledonUbuntu11.10andnewer.
$repoinit-bmaster
$reposync


Sourcesyncissues


Difficultiessyncingthesourcecode(proxyissues).
Symptom:
repoinit
or
reposync
failwithhttp
errors,typically403or500.
Cause:Therearequiteafewpossiblecauses,mostoftenrelatedtohttpproxies,whichhavedifficultieshandlingthelargeamountsofdatagettingtransfered.
Fix:Whilethere'snogeneralsolution,usingpython2.7andexplicitlyusing
reposync-j1
havebeenreportedtoimprove
thesituationforsomeusers.

Difficultiessyncingthesourcetree(VirtualBoxEthernetissues).
Symptom:Whenrunning
reposync
insomeVirtualBoxinstallations,theprocesshangsorfailswithavarietyofpossible
symptoms.Onesuchsymptomis
DownloadError:HTTP500(InternalServerError:Servergotitselfintrouble)
.
Cause:ThedefaultnetworkbehaviorofVirtualBoxistouseNAT(NetworkAddressTranslation)toconnecttheguestsystemtothenetwork.Theheavynetworkactivityofreposynctriggerssomecorner
casesintheNATcode.
Fix:ConfigureVirtualBoxtousebridgednetworkinsteadofNAT.

Difficultiessyncingthesourcetree(DNSissues).
Symptom:Whenrunning
reposync
,theprocessfailswithvariouserrorsrelatedtonotrecognizingthehostname.Onesuch
erroris
<urlopenerror[Errno-2]Nameorservicenotknown>
.
Cause:SomeDNSsystemshaveahardtimecopingwiththehighnumberofqueriesinvolvedinsyncingthesourcetree(therecanbeseveralhundredrequestsinaworst-casescenario).
Fix:Manuallyresolvetherelevanthostnames,andhard-codethoseresultslocally.
Youcanresolvethemwiththe
nslookup
command,whichwillgiveyouonenumericalIPaddressforeachofthose(typicallyinthe"Address"
partoftheoutput).
$nslookupgooglesource.com
$nslookupandroid.googlesource.com

Youcanthenhard-codethemlocallybyediting
/etc/hosts
,andaddingtwolinesinthatfile,oftheform:
aaa.bbb.ccc.dddgooglesource.com
eee.fff.ggg.hhhandroid.googlesource.com

Notethatthiswillonlyworkaslongastheservers'addressesdon'tchange,andiftheydoandyoucan'tconnectyou'llhavetoresolvethosehostnamesagainandedit
etc/hosts
accordingly.

Difficultiessyncingthesourcetree(TCPissues).
Symptom:
reposync
hangswhilesyncing,oftenwhenit'scompleted99%ofthesync.
Cause:SomesettingsintheTCP/IPstackcausedifficultiesinsomenetworkenvironments,suchthat
reposync
neithercompletes
norfails.
Fix:Onlinux,
sysctl-wnet.ipv4.tcp_window_scaling=0
.OnMacOS,disabletherfc1323extensioninthenetworksettings.

Runtimeissues

CameraandGPSdon'tworkonGalaxyNexus.
Symptom:CameraandGPSdon'tworkonGalaxyNexus.Asanexample,theCameraapplicationcrashesassoonasit'slaunched.
Cause:Thosehardwareperipheralsrequireproprietarylibrariesthataren'tavailableintheAndroidOpenSourceProject.
Fix:None.