- 系统版本
MacOS Mojave 10.14.5 - Xcode版本
Version11.3(11C29)
下载openJDK8源码
brew install mercurial
hg clone http://hg.openjdk.java.net/jdk8u/jdk8u-dev/
cd jdk8u-dev
bash ./get_source.sh
如果克隆失败，可以到http://hg.openjdk.java.net/jdk8u/jdk8u-dev/上面下载具体的模块zip或者tar.gz包进行解压；
下载下来后有以下几个的模块
| 模块 | Contains | 备注 |
|---|---|---|
| .(root) | 通用的配置和makefile文件 | |
| hotspot | 构建 OpenJDK 虚拟机的源码和make文件 | JVM源码 |
| langtools | OpenJDK javac和语言工具的源码 | jdk中提供的开发工具，比如javac,javap,jvisual以及一些国际化实现 |
| jdk | 构建openjdk运行时库和misc文件的源码和make文件 | jdk源码，编译后生成的则是Java运行时库和一些杂项库lib |
| jaxp | OpenJDK JAXP源码 | |
| jaxws | OpenJDK JAX-WS功能的源码 | |
| corba | OpenJDK Corba功能的源码 | |
| nashorn | OpenJDK JavaScript的源码 |
然后是配置环境变量
# 设定语言选项，必须设置
export LANG=C
# Mac平台，C编译器不再是GCC，而是clang
export CC=clang
export CXX=clang++
export CXXFLAGS=-stdlib=libc++
# 是否使用clang，如果使用的是GCC编译，该选项应该设置为false
export USE_CLANG=true
# 跳过clang的一些严格的语法检查，不然会将N多的警告作为Error
export COMPILER_WARNINGS_FATAL=false
# 链接时使用的参数
export LFLAGS='-Xlinker -lstdc++'
# 使用64位数据模型
export LP64=1
# 告诉编译平台是64位，不然会按照32位来编译
export ARCH_DATA_MODEL=64
# 允许自动下载依赖
export ALLOW_DOWNLOADS=true
# 并行编译的线程数，编译时长，为了不影响其他工作，可以选择2
export HOTSPOT_BUILD_JOBS=2
export PARALLEL_COMPILE_JOBS=2 #ALT_PARALLEL_COMPILE_JOBS=2
# 是否跳过与先前版本的比较
export SKIP_COMPARE_IMAGES=true
# 是否使用预编译头文件，加快编译速度
export USE_PRECOMPILED_HEADER=true
# 是否使用增量编译
export INCREMENTAL_BUILD=true
# 编译内容
export BUILD_LANGTOOL=true
export BUILD_JAXP=true
export BUILD_JAXWS=true
export BUILD_CORBA=true
export BUILD_HOTSPOT=true
export BUILD_JDK=true
# 编译版本
export SKIP_DEBUG_BUILD=true
export SKIP_FASTDEBUG_BULID=false
export DEBUG_NAME=debug
# 避开javaws和浏览器Java插件之类部分的build
export BUILD_DEPLOY=false
export BUILD_INSTALL=false
# 最后需要干掉这两个环境变量（如果你配置过），不然会发生诡异的事件
unset JAVA_HOME
unset CLASSPATH
编译JDK
准备的第三方
- freetype ：
brew install freetype - Xcode： Xcode11
- XQuartz：下载地址
configure
//release版本
bash ./configure --with-freetype-include=/usr/local/include/freetype2 --with-freetype-lib=/usr/local/lib/
//Xcode可断点调试的fast-debug版本
bash ./configure --enable-debug --with-target-bits=64 --with-freetype-include=/usr/local/include/freetype2 --with-freetype-lib=/usr/local/lib --with-boot-jdk=/Library/Java/JavaVirtualMachines/jdk1.8.0_201.jdk/Contents/Home CXX=clang++
成功之后会有类似于下面的输出
A new configuration has been successfully created in
/Users/y2ss/Desktop/java-study/jdk8u-dev/build/macosx-x86_64-normal-server-release
using configure arguments '--with-freetype-include=/usr/local/include/freetype2 --with-freetype-lib=/usr/local/lib/'.
Configuration summary:
* Debug level: release
* JDK variant: normal
* JVM variants: server
* OpenJDK target: OS: macosx, CPU architecture: x86, address length: 64
Tools summary:
* Boot JDK: java version "1.8.0_201" Java(TM) SE Runtime Environment (build 1.8.0_201-b09) Java HotSpot(TM) 64-Bit Server VM (build 25.201-b09, mixed mode) (at /Library/Java/JavaVirtualMachines/jdk1.8.0_201.jdk/Contents/Home)
* Toolchain: gcc (GNU Compiler Collection)
* C Compiler: Version Apple clang version 11.0.0 (clang-1100.0.33.16) Target: x86_64-apple-darwin18.6.0 Thread model: posix InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin (at /usr/bin/clang)
* C++ Compiler: Version Apple clang version 11.0.0 (clang-1100.0.33.16) Target: x86_64-apple-darwin18.6.0 Thread model: posix InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin (at /usr/bin/clang++)
Build performance summary:
* Cores to use: 2
* Memory limit: 8192 MB
可能会遇到的错误
1. configure: error: Xcode 4 is required to build JDK 8, the version found was 11.1
解决办法：vi common/autoconf/generated-configure.sh，注释掉下面代码
# Fail-fast: verify we're building on Xcode 4, we cannot build with Xcode 5 or later
XCODE_VERSION=`$XCODEBUILD -version | grep '^Xcode ' | sed 's/Xcode //'`
XC_VERSION_PARTS=( ${XCODE_VERSION//./ } )
if test ! "${XC_VERSION_PARTS[0]}" = "4"; then
as_fn_error $? "Xcode 4 is required to build JDK 8, the version found was $XCODE_VERSION. Use --with-xcode-path to specify the location of Xcode 4 or make Xcode 4 active by using xcode-select." "$LINENO" 5
fi
2. configure: error: GCC compiler is required. Try setting --with-tools-dir.
解决办法：vi common/autoconf/generated-configure.sh，注释掉所有以下代码
if test $? -ne 0; then
{ $as_echo "$as_me:${as_lineno-$LINENO}: The $COMPILER_NAME compiler (located as $COMPILER) does not seem to be the required GCC compiler." >&5
$as_echo "$as_me: The $COMPILER_NAME compiler (located as $COMPILER) does not seem to be the required GCC compiler." >&6;}
{ $as_echo "$as_me:${as_lineno-$LINENO}: The result from running with --version was: \"$COMPILER_VERSION_TEST\"" >&5
$as_echo "$as_me: The result from running with --version was: \"$COMPILER_VERSION_TEST\"" >&6;}
as_fn_error $? "GCC compiler is required. Try setting --with-tools-dir." "$LINENO" 5
fi
make all
执行make all
可能会遇到的错误
1. fatal error: 'iostream' file not found
找不到iostream库位置或者缺失，到这里下载源文件后按照install.sh的命令敲，但是在我电脑上没有用，后来无意间在config.log上面发现这段日志
将c++文件夹复制到
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include后解决；
2. ld: library not found for -lstdc++
解决办法： 缺失libstdc++库，同样把上面下载的文件中lib下面的libstdc*放到/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/lib后解决；
3. error: invalid argument '-std=gnu++98' not allowed with 'C'
解决办法：vi common/autoconf/generated-configure.sh找到CXXSTD_CXXFLAG="-std=gnu++98"并注释掉；然后清空build文件夹下面的文件，重新执行configure&&make all；
4. ld: symbol(s) not found for architecture x86_64
解决办法：在configure时候把参数--with-debug-level=slowdebug去掉，然后清空build文件夹下面的文件，重新执行configure&&make all；
或者说如果要使用slowdebug则需要修改jdk/src/macosx/native/sun/osxapp/ThreadUtilities.m中的attachCurrentThread方法上添加static；
漫长的等待后终于成功，输出如下
测试
cd macosx-x86_64-normal-server-release/jdk/bin/ && ./java -version
成功之后会输出
openjdk version "1.8.0-internal"
OpenJDK Runtime Environment (build 1.8.0-internal-y2ss_2020_02_25_18_12-b00)
OpenJDK 64-Bit Server VM (build 25.71-b00, mixed mode)
但是执行./java -version时遇到一个JVM crash
#
# A fatal error has been detected by the Java Runtime Environment:
#
# SIGILL (0x4) at pc=0x000000010fe801bf, pid=48116, tid=0x0000000000002203
#
# JRE version: OpenJDK Runtime Environment (8.0) (build 1.8.0-internal-zhengshuangxi_2019_06_21_16_42-b00)
# Java VM: OpenJDK 64-Bit Server VM (25.71-b00 mixed mode bsd-amd64 compressed oops)
# Problematic frame:
# V [libjvm.dylib+0x4801bf] PerfDataManager::destroy()+0xab
#
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#
# An error report file with more information is saved as:
#
# If you would like to submit a bug report, please visit:
# http://bugreport.java.com/bugreport/crash.jsp
#
[error occurred during error reporting , id 0x4]
Abort trap: 6
解决办法：在hotspot/src/share/vm/runtime/perfData.cpp文件中找到
void PerfDataManager::destroy() {
if (_all == NULL)
// destroy already called, or initialization never happened
return;
for (int index = 0; index < _all->length(); index++) {
PerfData* p = _all->at(index);
//delete p;
}
delete(_all);
delete(_sampled);
delete(_constants);
_all = NULL;
_sampled = NULL;
_constants = NULL;
}
调试
作为前iOS开发，看到能用Xcode调试就毫不犹豫的选择了这个，新建一个macOS工程
创建好后将project下面的文件删除
编辑scheme，在Build中将原来项目的target删除
在Executable中选择编译出来的java可执行程序
在Arguments中可以添加java的参数，比如-cp就是执行java字节码class文件，如果遇到错误: 找不到或无法加载主类 ArrayCopy.class，那就是编译出的java字节码文件有问题；
然后将openjdk目录导入到该项目下
就可以愉快的进行调试了
当然还会遇到以上情况，只需要在lldb中输入process handle SIGSEGV --stop=false然后点击下一步即可解决；
当然也可以像这篇文章一样在断点上面添加动作，避免每次都在lldb中输入；
参考
https://www.jianshu.com/p/d9a1e1072f37
https://www.cnblogs.com/kelthuzadx/p/10972992.html
https://www.zhoujunwen.com/2019/building-openjdk-8-on-mac-osx-catalina-10-15
