On 9/12/2014 9:16 PM, Xerxes Rånby wrote:
Den 2014-12-09 10:27, Severin Gehwolf skrev:
Hi,
On Mon, 2014-12-08 at 21:46 +1000, David Holmes wrote:
On 8/12/2014 7:10 PM, ChenLong wrote:
Hi
Apologize if this is not the right place to ask.
I want to try OpenJDK8 on Armv7. Is there a guideline on how to
cross compile OpenJDK8 for Armv7? And if not, could someone share
some experiences? I went through the README-builds.html and did not
find any clues for cross compiling.
The only OpenJDK build for ARM would be a ZERO build. But I don't know
how to do Zero builds - though I'm sure the Zero folk will chime in.
CC'ing zero-dev.
when I cross-compile OpenJDK 9 for ARM32 I pass the following configure
options
configure
# these options tell openjdk to do a cross compile build.
--build=x86_64-unknown-linux-gnu
--host=arm-buildroot-linux-gnueabi
--target=arm-buildroot-linux-gnueabi
# these two options enable zero
--with-jvm-interpreter=cpp
--with-jvm-variants=zero
# specific options to make the build find the X and freetype headers and
librarys found on the ARM32 root filesystem.
--disable-freetype-bundling
--with-freetype-include=/home/xranby/rpi-buildroot/output/host/usr/arm-buildroot-linux-gnueabi/sysroot/usr/include/freetype2
--with-freetype-lib=/home/xranby/rpi-buildroot/output/host/usr/arm-buildroot-linux-gnueabi/sysroot/usr/lib
--with-freetype=/home/xranby/rpi-buildroot/output/host/usr/arm-buildroot-linux-gnueabi/sysroot/usr/
--with-x=/home/xranby/rpi-buildroot/output/host/usr/arm-buildroot-linux-gnueabi/sysroot/usr/include
# the sysroot shall point to the ARM32 root file system, the build will
use librarys inside the sys root during linking native libraries.
--with-sys-root=/home/xranby/rpi-buildroot/output/host/usr/arm-buildroot-linux-gnueabi/sysroot
# The tools dir contains binarys to run on the host x86 system, you may
point this to your system root dir /
# in my case the tools i use have been compiled by buildroot thus I use
the buildroot tools dir.
--with-tools-dir=/home/xranby/rpi-buildroot/output/host
# OpenJDK 9 require OpenJDK 8, i point with boot jdk to an OpenJDK 8
image that can be run on the host x86 system.
--with-boot-jdk=/home/xranby/images-jdk8/j2sdk-image/
# some parts of the openjdk build still expect that the cross compile
tools are found in the system PATH
No that should not be the case. If you have set the tools-dir or
--with-devkit to point to your cross-compiler tool-chain then it will
use those without need to set all the build tool variables manually.
David
-----
# on my system i have to explicitly tell where the tools are located
because my cross compile toolchain is not found on the path.
# i use gcc to do the linking instead of ld because the openjdk build
passes -Xlinker -z
OBJCOPY=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-objcopy
STRIP=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-strip
CPP=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-cpp
CXX=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-g++
CC=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-gcc
LD=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-gcc
CPP_FLAGS=-lstdc++
CXX_FLAGS=-lstdc++
when running make i pass the following options to make
# BUILD_CC and BUILD_LD shall point to host x86 executables.
BUILD_CC=gcc
BUILD_LD=gcc
OBJCOPY=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-objcopy
STRIP=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-strip
CPP=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-cpp
CXX=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-g++
CC=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-gcc
LD=/home/xranby/rpi-buildroot/output/host/usr/bin/arm-buildroot-linux-gnueabi-gcc
#and finally the target, this will build compact profiles, jre and jdk
images.
all images profiles CONF=linux-arm-normal-zero-release
I have automated these configure and make options for openjdk 9 into
buildroot build scripts
https://github.com/xranby/rpi-buildroot/tree/openjdk
I've done Zero builds before but have never used OpenJDK's cross-compile
feature to build it on ARMv7. There is an Arm32 bit JIT in IcedTea[1],
but I don't know if that can be cross-compiled.
If you cross compile icedtea then you need to make sure that the
bytecode generator tool is compiled by the host x86 toolchain.
openembedded meta-java contains buildscripts that can cross compile the
Arm32 JIT found in IcedTea.
https://github.com/woglinde/meta-java
Cheers
Xerxes
Cheers,
Severin
[1]
http://blog.fuseyism.com/index.php/2014/03/28/icedtea-2-3-14-2-4-6-considered-armful-released/
David
Thanks
Chen Long
