1 page.title=ndk-build 2 @jd:body 3 4 <div id="qv-wrapper"> 5 <div id="qv"> 6 <h2>On this page</h2> 7 8 <ol> 9 <li><a href="#int">Internals</a></li> 10 <li><a href="#ifc">Invoking from the Command Line</a></li> 11 <li><a href="#6432">64-Bit and 32-Bit Toolchains</a></li> 12 <li><a href="#req">Requirements</a></li> 13 </ol> 14 </li> 15 </ol> 16 </div> 17 </div> 18 19 <p>The {@code ndk-build} file is a shell script introduced in Android NDK r4. Its purpose 20 is to invoke the right NDK build script. 21 22 <h2 id="int">Internals</h2> 23 24 <p>Running the {@code ndk-build} script is equivalent to running the following command:</p> 25 26 <pre class="no-pretty-print"> 27 $GNUMAKE -f <ndk>/build/core/build-local.mk 28 <parameters> 29 </pre> 30 31 <p><code>$GNUMAKE</code> points to GNU Make 3.81 or later, and 32 <code><ndk></code> points to your NDK installation directory. You can use 33 this information to invoke ndk-build from other shell scripts, or even your own 34 make files.</p> 35 36 <h2 id="ifc">Invoking from the Command Line</h2> 37 <p>The {@code ndk-build} file lives in the top level the NDK installation directory. To run it 38 from the command line, invoke it while in or under your application project directory. 39 For example: </p> 40 41 <pre class="no-pretty-print"> 42 cd <project> 43 $ <ndk>/ndk-build 44 </pre> 45 46 <p>In this example, <code><project></code> points to your 47 projects root directory, and <code><ndk></code> is the directory where 48 you installed the NDK.</p> 49 50 <p><a class="anchor" id="options"></a> </p> 51 <h3>Options</h3> 52 <p>All parameters to ndk-build are passed directly to the underlying GNU {@code make} 53 command that runs the NDK build scripts. Combine <code>ndk-build</code> and 54 options in the form <code>ndk-build <option></code>. For example: </p> 55 56 <pre class="no-pretty-print"> 57 $ ndk-build clean 58 </pre> 59 60 <p>The following options are available:</p> 61 <dl> 62 <dt>{@code clean}</dt> 63 <dd>Remove any previously generated binaries.</dd> 64 <dt>{@code V=1}</dt> 65 <dd>Launch build, and display build commands.<dd> 66 <dt>{@code -B}</dt> 67 <dd>Force a complete rebuild.</dd> 68 <dt>{@code -B V=1}</dt> 69 <dd>Force a complete rebuild, and display build commands.</dd> 70 <dt>{@code NDK_LOG=1}</dd> 71 <dd>Display internal NDK log messages (used for debugging the NDK itself).</dd> 72 <dt>{@code NDK_DEBUG=1}</dt> 73 <dd>Force a debuggable build (see <a href="#dvr">Table 1</a>).</dd> 74 <dt>{@code NDK_DEBUG=0}</dt> 75 <dd>Force a release build (see <a href="#dvr">Table 1</a>).</dd> 76 <dt>{@code NDK_HOST_32BIT=1}</dt> 77 <dd>Always use the toolchain in 32-bit mode (see <a href="#6432">64-bit and 32-bit 78 Toolchains</a>).</dd> 79 <dt>{@code NDK_APPLICATION_MK=<file>}</dt> 80 <dd>Build, using a specific <code>Application.mk</code> file pointed to by the 81 {@code NDK_APPLICATION_MK} variable.</dd> 82 <dt>{@code -C <project>}</dt> 83 <dd>Build the native code for the project path located at {@code <project>}. Useful if you 84 don't want to {@code cd} to it in your terminal.</dd> 85 </dl> 86 87 <p><a class="anchor" id="dvr"></a> </p> 88 <h3>Debuggable versus Release builds</h3> 89 <p>Use the <code>NDK_DEBUG</code> option and, in certain cases, 90 {@code AndroidManifest.xml} to specify debug or release build, 91 optimization-related behavior, and inclusion of symbols. Table 1 shows the 92 results of each possible combination of settings.</p> 93 <p><em>Table 1.</em> Results of <code>NDK_DEBUG</code> (command line) and 94 <code>android:debuggable</code> (manifest) combinations.</p> 95 <table> 96 <tr> 97 <th></th><th>NDK_DEBUG=0 </th><th>NDK_DEBUG=1</th><th>NDK_DEBUG not specified 98 </th></tr> 99 <tr> 100 <td>android:debuggble="true" </td><td>Debug; Symbols; Optimized*1 101 </td><td>Debug; Symbols; Not optimized*2 </td><td>(same as NDK_DEBUG=1) 102 </td></tr> 103 <tr> 104 <td>android:debuggable="false"</td><td>Release; Symbols; Optimized 105 </td><td>Release; Symbols; Not optimized</td><td>Release; No symbols; 106 Optimized*3 </td></tr> 107 </table> 108 *1: Useful for profiling.<br> 109 *2: Default for running <a href="{@docRoot}ndk/guides/ndk-gdb.html">{@code ndk-gdb}</a>.<br> 110 *3: Default mode.<br> 111 <br> 112 <p class="note"><strong>Note:</strong> {@code NDK_DEBUG=0} is the equivalent of 113 {@code APP_OPTIM=release}, and complies with the GCC {@code -O2} option. {@code NDK_DEBUG=1} is the 114 equivalent of {@code APP_OPTIM=debug} in {@code Application.mk}, and complies with the GCC 115 {@code -O0} option. For more information about {@code APP_OPTIM}, see 116 <a href="{@docRoot}ndk/guides/application_mk.html">Application.mk</a>.</p> 117 <p>The syntax on the command line is, for example: </p> 118 119 <pre class="no-pretty-print"> 120 $ ndk-build NDK_DEBUG=1 121 </pre> 122 123 <p>If you are using build tools from prior to SDK r8, you must also modify your 124 {@code AndroidManifest.xml} file to specify debug mode. The syntax for doing so resembles the 125 following:</p> 126 127 <pre class="no-pretty-print"><application android:label="@string/app_name" 128 android:debuggable="true"> 129 </pre> 130 131 From SDK r8 onward, you do not need to touch {@code AndroidManifest.xml}. Building a debug package 132 (e.g. with ant debug or the corresponding option of the ADT plugin) causes the tool automatically to 133 pick the native debug files generated with {@code NDK_DEBUG=1}. 134 135 136 <h2 id="6432">64-Bit and 32-Bit Toolchains</h2> 137 <p>Some toolchains come with both 64-bit and 32-bit versions. For example, 138 directories {@code <ndk>/toolchain/<name>/prebuilt/} and 139 {@code <ndk>/prebuilt/} may contain both {@code linux-x86} and 140 {@code linux-x86_64} folders for Linux tools in 32-bit and 64-bit modes, 141 respectively. The ndk-build script automatically chooses a 64-bit version of 142 the toolchain if the host OS supports it. You can force the use of a 32-bit 143 toolchain by using {@code NDK_HOST_32BIT=1} either in your environment or 144 on the ndk-build command line.</p> 145 <p>Note that 64-bit tools utilize host resources better (for instance, they are faster, and handle 146 larger programs), and they can still generate 32-bit binaries for Android.</p> 147 148 <h2 id="req">Requirements</h2> 149 <p>You need GNU Make 3.81 or later to use ndk-build or the NDK in general. 150 The build scripts will detect a non-compliant Make tool, and generate an error 151 message.</p> 152 <p>If you have GNU Make 3.81 installed, but the default <code>make</code> 153 command doesnt launch it, define {@code GNUMAKE} in your environment to point to it 154 before launching ndk-build. For example: </p> 155 156 <pre class="no-pretty-print"> 157 $ export GNUMAKE=/usr/local/bin/gmake 158 $ ndk-build 159 </pre> 160 161 <p>You can override other host prebuilt tools in {@code $NDK/prebuilt/<OS>/bin/} 162 with the following environment variables: </p> 163 164 <pre class="no-pretty-print"> 165 $ export NDK_HOST_AWK=<path-to-awk> 166 $ export NDK_HOST_ECHO=<path-to-echo> 167 $ export NDK_HOST_CMP=<path-to-cmp> 168 </pre> 169
