android编译单独模块时异常提示

lqm@lqm:~/android_gingerbread$ make ledtestapp============================================PLATFORM_VERSION_CODENAME=RELPLATFORM_VERSION=2.3.1TARGET_PRODUCT=genericTARGET_BUILD_VARIANT=engTARGET_SIMULATOR=TARGET_BUILD_TYPE=releaseTARGET_BUILD_APPS=TARGET_ARCH=armHOST_ARCH=x86HOST_OS=linuxHOST_BUILD_TYPE=releaseBUILD_ID=GINGERBREAD============================================build/core/base_rules.mk:74: *** Module name: ledtestappbuild/core/base_rules.mk:75: *** Makefile location: external/ledbuild/core/base_rules.mk:76: * build/core/base_rules.mk:77: * Each module must use a LOCAL_MODULE_TAGS in itsbuild/core/base_rules.mk:78: * Android.mk. Possible tags declared by a module:build/core/base_rules.mk:79: * build/core/base_rules.mk:80: *     optional, debug, eng, tests, samplesbuild/core/base_rules.mk:81: * build/core/base_rules.mk:82: * If the module is expected to be in all buildsbuild/core/base_rules.mk:83: * of a product, then it should use thebuild/core/base_rules.mk:84: * "optional" tag: build/core/base_rules.mk:85: * build/core/base_rules.mk:86: *    Add "LOCAL_MODULE_TAGS := optional" in thebuild/core/base_rules.mk:87: *    Android.mk for the affected module, and addbuild/core/base_rules.mk:88: *    the LOCAL_MODULE value for that componentbuild/core/base_rules.mk:89: *    into the PRODUCT_PACKAGES section of productbuild/core/base_rules.mk:90: *    makefile(s) where it's necessary, ifbuild/core/base_rules.mk:91: *    appropriate.build/core/base_rules.mk:92: * build/core/base_rules.mk:93: * If the component should be in EVERY build of ALLbuild/core/base_rules.mk:94: * products, then add its LOCAL_MODULE value to thebuild/core/base_rules.mk:95: * PRODUCT_PACKAGES section ofbuild/core/base_rules.mk:96: * build/target/product/core.mkbuild/core/base_rules.mk:97: * build/core/base_rules.mk:98: *** user tag detected on new module - user tags are only supported on legacy modules。 停止

解决办法；

add LOCAL_MODULE_TAGS := optional in Android.mk where the error happens