LOCAL_MODULE_TAGS 选项说明

1,LOCAL_MODULE_TAGS ：=user \ eng \ tests \ optional

user:指该模块只在user版本下才编译

eng:指该模块只在eng版本下才编译

tests:指该模块只在tests版本下才编译

optional:指该模块在所有版本下都编译

(1),eng This is the default flavor. A plain "make" is the same as "make eng". droid is an alias for eng.
* Installs modules tagged with: eng, debug, user, and/or development.
* Installs non-APK modules that have no tags specified.
* Installs APKs according to the product definition files, in addition to tagged APKs.
* ro.secure=0
* ro.debuggable=1
* ro.kernel.android.checkjni=1
* adb is enabled by default.

(2),user "make user"This is the flavor intended to be the final release bits.
* Installs modules tagged with user.
* Installs non-APK modules that have no tags specified.
* Installs APKs according to the product definition files; tags are ignored for APK modules.
* ro.secure=1
* ro.debuggable=0
* adb is disabled by default.

(3)userdebug "make userdebug"The same as user, except:
* Also installs modules tagged with debug.
* ro.debuggable=1
* adb is enabled by default.

2,Build flavors/types

When building for a particular product, it's often useful to have minor variations on what is ultimately the final release build. These are the currently-defined "flavors" or "types" (we need to settle on a real name for these).

eng	This is the default flavor. A plain "make" is the same as "make eng".droidis an alias foreng. Installs modules tagged with:eng,debug,user, and/ordevelopment. Installs non-APK modules that have no tags specified. Installs APKs according to the product definition files, in addition to tagged APKs. ro.secure=0 ro.debuggable=1 ro.kernel.android.checkjni=1 adbis enabled by default.
user	"make user" This is the flavor intended to be the final release bits. Installs modules tagged withuser. Installs non-APK modules that have no tags specified. Installs APKs according to the product definition files; tags are ignored for APK modules. ro.secure=1 ro.debuggable=0 adbis disabled by default.
userdebug	"make userdebug" The same asuser, except: Also installs modules tagged withdebug. ro.debuggable=1 adbis enabled by default.

If you build one flavor and then want to build another, you should run "make installclean" between the two makes to guarantee that you don't pick up files installed by the previous flavor. "make clean" will also suffice, but it takes a lot longer.

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Android 编译重要参数 LOCAL_MODULE_TAGS(转)

最近移植tslib库到android系统，发现编译好的库和测试工具竟然没有输入到out/target/product/Ok6410/system/lib 和 out/target/product/Ok6410/system/bin下面，感觉很奇怪，于是下定决心看一下，到底输入到了哪里。

过程如下：

tslib的源代码放到了android2.3 源代码下vendor 目录 （android2.3中自己添加，如何设置自己的vendor 我的博客中有说明）forlinx/OK6410/的下面.tslib目录下面的 Android.mk写好以后，重新make clean 整个android源码，再次make 编译通过，奇怪的是输出目录 out/target/product/Ok6410/system/bin 下面竟然没有tslib相关的工具，而是放在了out/target/product/OK6410/symbols/system/bin 下面，在做打包文件时，由于没有把symbols文件夹放到文件系统里面，所以校准功能不能实现。（事实上提取文件系统过程中也不应该把symbols文件夹考虑在内）。

最后查找原因 ：因为tslib文件下的Android.mk文件里面，LOCAL_MODULE_TAGS变量设置的有问题。

LOCAL_MODULE_TAGS :=optional

把这项改为

LOCAL_MODULE_TAGS :=eng

即可

原因是LOCAL_MODULE_TAGS变量跟TARGET_BUILD_VARIANT 变量息息相关。android系统编译时如果不指定TARGET_BUILD_VARIANT 变量的值，默认TARGET_BUILD_VARIANT=eng ，这一项指定 编译android时形成的版本风格，一般发布时使用这个值,当然还有user,debuguser等风格值。

具体看一下这个链接

http://android.git.kernel.org/?p=platform/build.git;a=blob_plain;f=core/build-system.html;h=43bae03b6b7b9cba678b86d2faf424fa565497bf;hb=HEAD，

如果打不开，翻个墙就可以。这样设置好以后，重新编译，输出目录out/target/product/Ok6410/system/bin,out/target/product/Ok6410/system/lib里面就有tslib相关的库和测试程序了。

由些看来，如果自己需要加额外的模块，或者应用程序，一定要注意Android.mk里面的这个变量，当然了，如果你指定了LOCAL_MODULE_TAGS :=optional,也能编译出来，但是存放的输入路径就不是一般的

out/target/product/Ok6410/system/目录了，而是out/target/product/OK6410/symbols/system/目录。

后来自己在android源代码的 external目录下面放了一个模块，指定该模块的编译风格为LOCAL_MODULE_TAGS :=optional,重新编译，通过以后，竟然直接输出到了out/target/product/Ok6410/system/ 目录，很是惊讶，个人认为还跟模块存放的目录有关.所以无论模块在哪个文件夹下面，最好指定的值跟TARGET_BUILD_VARIANT 相关，如果没指定TARGET_BUILD_VARIANT ，系统会默认设置TARGET_BUILD_VARIANT =eng,你也就指定LOCAL_MODULE_TAGS :=eng

目前自己遇到的 vendor目录，hardware目录下面的模块输出路径跟LOCAL_MODULE_TAGS 有很大的关系

LOCAL_MODULE_TAGS :=optional>> out/target/product/OK6410/symbols/system/

LOCAL_MODULE_TAGS :=eng >> out/target/product/Ok6410/system/

当然前提是TARGET_BUILD_VARIANT=eng .

下面是网友遇到的类似问题：

"Set LOCAL_MODULE_TAGS to any number of whitespace-separated tags.

This variable controls what build flavors the package gets included
in. For example:

* user: include this in user/userdebug builds
* eng: include this in eng builds
* tests: the target is a testing target and makes it available for tests
* optional: don't include this"

Are these the same as "variants" and if so, which name would affectthe build and how? I've noticed that everything mentioned in a
product's makefile will always get built. But what gets in the finalsystem.img not always the same as what gets built.
http://groups.google.com.tw/group/android-platform/browse_thread/thread/a4f70254a2ceb622
http://android.git.kernel.org/?p=platform/build.git;a=blob_plain;f=core/build-system.html;h=43bae03b6b7b9cba678b86d2faf424fa565497bf;hb=HEAD

以上是自己在移植android2.3过程中发现的一个问题，如果您也遇到了，并且认为我的解释存在问题，请指出，以免给大家带来误解。