266 <tr class="odd">
267 <td style="text-align: left;">Linux</td>
268 <td style="text-align: left;">gcc 9.2.0</td>
269 </tr>
270 <tr class="even">
271 <td style="text-align: left;">macOS</td>
272 <td style="text-align: left;">Apple Xcode 10.1 (using clang 10.0.0)</td>
273 </tr>
274 <tr class="odd">
275 <td style="text-align: left;">Windows</td>
276 <td style="text-align: left;">Microsoft Visual Studio 2019 update 16.5.3</td>
277 </tr>
278 </tbody>
279 </table>
280 <p>All compilers are expected to be able to compile to the C99 language standard, as some C99 features are used in the source code. Microsoft Visual Studio doesn't fully support C99 so in practice shared code is limited to using C99 features that it does support.</p>
281 <h3 id="gcc">gcc</h3>
282 <p>The minimum accepted version of gcc is 5.0. Older versions will generate a warning by <code>configure</code> and are unlikely to work.</p>
283 <p>The JDK is currently known to be able to compile with at least version 9.2 of gcc.</p>
284 <p>In general, any version between these two should be usable.</p>
285 <h3 id="clang">clang</h3>
286 <p>The minimum accepted version of clang is 3.2. Older versions will not be accepted by <code>configure</code>.</p>
287 <p>To use clang instead of gcc on Linux, use <code>--with-toolchain-type=clang</code>.</p>
288 <h3 id="apple-xcode">Apple Xcode</h3>
289 <p>The oldest supported version of Xcode is 8.</p>
290 <p>You will need the Xcode command lines developers tools to be able to build the JDK. (Actually, <em>only</em> the command lines tools are needed, not the IDE.) The simplest way to install these is to run:</p>
291 <pre><code>xcode-select --install</code></pre>
292 <p>It is advisable to keep an older version of Xcode for building the JDK when updating Xcode. This <a href="http://iosdevelopertips.com/xcode/install-multiple-versions-of-xcode.html">blog page</a> has good suggestions on managing multiple Xcode versions. To use a specific version of Xcode, use <code>xcode-select -s</code> before running <code>configure</code>, or use <code>--with-toolchain-path</code> to point to the version of Xcode to use, e.g. <code>configure --with-toolchain-path=/Applications/Xcode8.app/Contents/Developer/usr/bin</code></p>
293 <p>If you have recently (inadvertently) updated your OS and/or Xcode version, and the JDK can no longer be built, please see the section on <a href="#problems-with-the-build-environment">Problems with the Build Environment</a>, and <a href="#getting-help">Getting Help</a> to find out if there are any recent, non-merged patches available for this update.</p>
294 <h3 id="microsoft-visual-studio">Microsoft Visual Studio</h3>
295 <p>The minimum accepted version of Visual Studio is 2010. Older versions will not be accepted by <code>configure</code>. The maximum accepted version of Visual Studio is 2019. Versions older than 2017 are unlikely to continue working for long.</p>
296 <p>If you have multiple versions of Visual Studio installed, <code>configure</code> will by default pick the latest. You can request a specific version to be used by setting <code>--with-toolchain-version</code>, e.g. <code>--with-toolchain-version=2015</code>.</p>
297 <p>If you get <code>LINK: fatal error LNK1123: failure during conversion to COFF: file invalid</code> when building using Visual Studio 2010, you have encountered <a href="http://support.microsoft.com/kb/2757355">KB2757355</a>, a bug triggered by a specific installation order. However, the solution suggested by the KB article does not always resolve the problem. See <a href="https://stackoverflow.com/questions/10888391">this stackoverflow discussion</a> for other suggestions.</p>
298 <h3 id="ibm-xl-cc">IBM XL C/C++</h3>
299 <p>Please consult the AIX section of the <a href="https://wiki.openjdk.java.net/display/Build/Supported+Build+Platforms">Supported Build Platforms</a> OpenJDK Build Wiki page for details about which versions of XLC are supported.</p>
300 <h2 id="boot-jdk-requirements">Boot JDK Requirements</h2>
301 <p>Paradoxically, building the JDK requires a pre-existing JDK. This is called the "boot JDK". The boot JDK does not, however, have to be a JDK built directly from the source code available in the OpenJDK Community. If you are porting the JDK to a new platform, chances are that there already exists another JDK for that platform that is usable as boot JDK.</p>
302 <p>The rule of thumb is that the boot JDK for building JDK major version <em>N</em> should be a JDK of major version <em>N-1</em>, so for building JDK 9 a JDK 8 would be suitable as boot JDK. However, the JDK should be able to "build itself", so an up-to-date build of the current JDK source is an acceptable alternative. If you are following the <em>N-1</em> rule, make sure you've got the latest update version, since JDK 8 GA might not be able to build JDK 9 on all platforms.</p>
303 <p>Early in the release cycle, version <em>N-1</em> may not yet have been released. In that case, the preferred boot JDK will be version <em>N-2</em> until version <em>N-1</em> is available.</p>
304 <p>If the boot JDK is not automatically detected, or the wrong JDK is picked, use <code>--with-boot-jdk</code> to point to the JDK to use.</p>
305 <h3 id="getting-jdk-binaries">Getting JDK binaries</h3>
306 <p>JDK binaries for Linux, Windows and macOS can be downloaded from <a href="http://jdk.java.net">jdk.java.net</a>. An alternative is to download the <a href="http://www.oracle.com/technetwork/java/javase/downloads">Oracle JDK</a>. Another is the <a href="https://adoptopenjdk.net/">Adopt OpenJDK Project</a>, which publishes experimental prebuilt binaries for various platforms.</p>
307 <p>On Linux you can also get a JDK from the Linux distribution. On apt-based distros (like Debian and Ubuntu), <code>sudo apt-get install openjdk-<VERSION>-jdk</code> is typically enough to install a JDK <VERSION>. On rpm-based distros (like Fedora and Red Hat), try <code>sudo yum install java-<VERSION>-openjdk-devel</code>.</p>
308 <h2 id="external-library-requirements">External Library Requirements</h2>
309 <p>Different platforms require different external libraries. In general, libraries are not optional - that is, they are either required or not used.</p>
310 <p>If a required library is not detected by <code>configure</code>, you need to provide the path to it. There are two forms of the <code>configure</code> arguments to point to an external library: <code>--with-<LIB>=<path></code> or <code>--with-<LIB>-include=<path to include> --with-<LIB>-lib=<path to lib></code>. The first variant is more concise, but require the include files and library files to reside in a default hierarchy under this directory. In most cases, it works fine.</p>
311 <p>As a fallback, the second version allows you to point to the include directory and the lib directory separately.</p>
312 <h3 id="freetype">FreeType</h3>
313 <p>FreeType2 from <a href="http://www.freetype.org/">The FreeType Project</a> is not required on any platform. The exception is on Unix-based platforms when configuring such that the build artifacts will reference a system installed library, rather than bundling the JDK's own copy.</p>
314 <ul>
315 <li>To install on an apt-based Linux, try running <code>sudo apt-get install libfreetype6-dev</code>.</li>
316 <li>To install on an rpm-based Linux, try running <code>sudo yum install freetype-devel</code>.</li>
317 </ul>
|
266 <tr class="odd">
267 <td style="text-align: left;">Linux</td>
268 <td style="text-align: left;">gcc 9.2.0</td>
269 </tr>
270 <tr class="even">
271 <td style="text-align: left;">macOS</td>
272 <td style="text-align: left;">Apple Xcode 10.1 (using clang 10.0.0)</td>
273 </tr>
274 <tr class="odd">
275 <td style="text-align: left;">Windows</td>
276 <td style="text-align: left;">Microsoft Visual Studio 2019 update 16.5.3</td>
277 </tr>
278 </tbody>
279 </table>
280 <p>All compilers are expected to be able to compile to the C99 language standard, as some C99 features are used in the source code. Microsoft Visual Studio doesn't fully support C99 so in practice shared code is limited to using C99 features that it does support.</p>
281 <h3 id="gcc">gcc</h3>
282 <p>The minimum accepted version of gcc is 5.0. Older versions will generate a warning by <code>configure</code> and are unlikely to work.</p>
283 <p>The JDK is currently known to be able to compile with at least version 9.2 of gcc.</p>
284 <p>In general, any version between these two should be usable.</p>
285 <h3 id="clang">clang</h3>
286 <p>The minimum accepted version of clang is 3.5. Older versions will not be accepted by <code>configure</code>.</p>
287 <p>To use clang instead of gcc on Linux, use <code>--with-toolchain-type=clang</code>.</p>
288 <h3 id="apple-xcode">Apple Xcode</h3>
289 <p>The oldest supported version of Xcode is 8.</p>
290 <p>You will need the Xcode command lines developers tools to be able to build the JDK. (Actually, <em>only</em> the command lines tools are needed, not the IDE.) The simplest way to install these is to run:</p>
291 <pre><code>xcode-select --install</code></pre>
292 <p>It is advisable to keep an older version of Xcode for building the JDK when updating Xcode. This <a href="http://iosdevelopertips.com/xcode/install-multiple-versions-of-xcode.html">blog page</a> has good suggestions on managing multiple Xcode versions. To use a specific version of Xcode, use <code>xcode-select -s</code> before running <code>configure</code>, or use <code>--with-toolchain-path</code> to point to the version of Xcode to use, e.g. <code>configure --with-toolchain-path=/Applications/Xcode8.app/Contents/Developer/usr/bin</code></p>
293 <p>If you have recently (inadvertently) updated your OS and/or Xcode version, and the JDK can no longer be built, please see the section on <a href="#problems-with-the-build-environment">Problems with the Build Environment</a>, and <a href="#getting-help">Getting Help</a> to find out if there are any recent, non-merged patches available for this update.</p>
294 <h3 id="microsoft-visual-studio">Microsoft Visual Studio</h3>
295 <p>The minimum accepted version of Visual Studio is 2017. Older versions will not be accepted by <code>configure</code> and will not work. The maximum accepted version of Visual Studio is 2019.</p>
296 <p>If you have multiple versions of Visual Studio installed, <code>configure</code> will by default pick the latest. You can request a specific version to be used by setting <code>--with-toolchain-version</code>, e.g. <code>--with-toolchain-version=2017</code>.</p>
297 <h3 id="ibm-xl-cc">IBM XL C/C++</h3>
298 <p>Please consult the AIX section of the <a href="https://wiki.openjdk.java.net/display/Build/Supported+Build+Platforms">Supported Build Platforms</a> OpenJDK Build Wiki page for details about which versions of XLC are supported.</p>
299 <h2 id="boot-jdk-requirements">Boot JDK Requirements</h2>
300 <p>Paradoxically, building the JDK requires a pre-existing JDK. This is called the "boot JDK". The boot JDK does not, however, have to be a JDK built directly from the source code available in the OpenJDK Community. If you are porting the JDK to a new platform, chances are that there already exists another JDK for that platform that is usable as boot JDK.</p>
301 <p>The rule of thumb is that the boot JDK for building JDK major version <em>N</em> should be a JDK of major version <em>N-1</em>, so for building JDK 9 a JDK 8 would be suitable as boot JDK. However, the JDK should be able to "build itself", so an up-to-date build of the current JDK source is an acceptable alternative. If you are following the <em>N-1</em> rule, make sure you've got the latest update version, since JDK 8 GA might not be able to build JDK 9 on all platforms.</p>
302 <p>Early in the release cycle, version <em>N-1</em> may not yet have been released. In that case, the preferred boot JDK will be version <em>N-2</em> until version <em>N-1</em> is available.</p>
303 <p>If the boot JDK is not automatically detected, or the wrong JDK is picked, use <code>--with-boot-jdk</code> to point to the JDK to use.</p>
304 <h3 id="getting-jdk-binaries">Getting JDK binaries</h3>
305 <p>JDK binaries for Linux, Windows and macOS can be downloaded from <a href="http://jdk.java.net">jdk.java.net</a>. An alternative is to download the <a href="http://www.oracle.com/technetwork/java/javase/downloads">Oracle JDK</a>. Another is the <a href="https://adoptopenjdk.net/">Adopt OpenJDK Project</a>, which publishes experimental prebuilt binaries for various platforms.</p>
306 <p>On Linux you can also get a JDK from the Linux distribution. On apt-based distros (like Debian and Ubuntu), <code>sudo apt-get install openjdk-<VERSION>-jdk</code> is typically enough to install a JDK <VERSION>. On rpm-based distros (like Fedora and Red Hat), try <code>sudo yum install java-<VERSION>-openjdk-devel</code>.</p>
307 <h2 id="external-library-requirements">External Library Requirements</h2>
308 <p>Different platforms require different external libraries. In general, libraries are not optional - that is, they are either required or not used.</p>
309 <p>If a required library is not detected by <code>configure</code>, you need to provide the path to it. There are two forms of the <code>configure</code> arguments to point to an external library: <code>--with-<LIB>=<path></code> or <code>--with-<LIB>-include=<path to include> --with-<LIB>-lib=<path to lib></code>. The first variant is more concise, but require the include files and library files to reside in a default hierarchy under this directory. In most cases, it works fine.</p>
310 <p>As a fallback, the second version allows you to point to the include directory and the lib directory separately.</p>
311 <h3 id="freetype">FreeType</h3>
312 <p>FreeType2 from <a href="http://www.freetype.org/">The FreeType Project</a> is not required on any platform. The exception is on Unix-based platforms when configuring such that the build artifacts will reference a system installed library, rather than bundling the JDK's own copy.</p>
313 <ul>
314 <li>To install on an apt-based Linux, try running <code>sudo apt-get install libfreetype6-dev</code>.</li>
315 <li>To install on an rpm-based Linux, try running <code>sudo yum install freetype-devel</code>.</li>
316 </ul>
|