I'm trying to compile bnep as a module (needed for Bluetooth PAN), but I keep running into the following error when I try to load it:
insmod: init_module 'bnep.ko' failed (Exec format error)
Click to expand...
Click to collapse
I'm using kernel-android-msm-htc-2.6.25 and arm-eabi-4.2.1-gcc from the android source, so I'm not sure what's wrong. Anyone have any pointers?
rale00 said:
I'm trying to compile bnep as a module (needed for Bluetooth PAN), but I keep running into the following error when I try to load it:
I'm using kernel-android-msm-htc-2.6.25 and arm-eabi-4.2.1-gcc from the android source, so I'm not sure what's wrong. Anyone have any pointers?
Click to expand...
Click to collapse
hmm. good question. Unfortunately I don't have any advice right now :\. But it sounds interesting and now I want to see if I can build a minimal do-nothing kernel module and get it to load.
More to come
No joy here. I couldn't even figure out how to get it to compile a minimal "hello world" kernel module.
I am trying to make a driver too. But I am still not sure how to compile a module.
I was trying to make the whole source tree from my redhat machine, but no luck.
So instead, I plan to just compile my driver by using the toolchain from android source.
But I am sure how to make a makefile for this.
Could you share it?
Thanks,
Blues
The "exec format error" means that you compiled it for the wrong architecture.
For a quick reference to seeing what arch for which a binary is compiled, use the "file" command found on any Linux computer (but not present on the phone itself).
The file command is an extremely useful function for identifying files -- including files that are packaged together, such as the .img files in the updates (see the -k option).
Dynamically linked executable:
"ELF 32-bit LSB executable, ARM, version 1 (SYSV), dynamically linked (uses shared libs), not stripped"
Statically linked executable:
"ELF 32-bit LSB executable, ARM, version 1 (SYSV), statically linked, stripped"
Object file:
"ELF 32-bit LSB relocatable, ARM, version 1 (SYSV), not stripped"
More specifically, if it doesn't say 32bit ARM, it will not work.
This may prove useful to some:
http://www.gentoo.org/proj/en/base/embedded/handbook/index.xml?part=1&chap=6
(And the compilers references in "CROSS_COMPILING" must be in your path -- see also the CC variable)
This is file on wlan.ko pulled directly from the phone - a known working module:
wlan.ko: ELF 32-bit LSB relocatable, ARM, version 1 (SYSV), not stripped
This is the module I compiled:
bnep.ko: ELF 32-bit LSB relocatable, ARM, version 1 (SYSV), not stripped
There must be something else at work here...
I am having same problem now. I am also using the toolchain from Android source...
I haven't gotten this deep into Android yet, but make sure the kernel source tree you're compiling against is the same version as the kernel on the phone. Modules compiled for a different kernel version will not load on another one (usually).
rale00 said:
This is file on wlan.ko pulled directly from the phone - a known working module:
wlan.ko: ELF 32-bit LSB relocatable, ARM, version 1 (SYSV), not stripped
This is the module I compiled:
bnep.ko: ELF 32-bit LSB relocatable, ARM, version 1 (SYSV), not stripped
There must be something else at work here...
Click to expand...
Click to collapse
Right after you try to insmod the module, type dmesg. Look through the last part of the output and see if there is anything helpful..
yeah, that's the problem.
The version magic number doesn't match.
May I know where to get the RC19 source tree? Thanks.
JesusFreke said:
Right after you try to insmod the module, type dmesg. Look through the last part of the output and see if there is anything helpful..
Click to expand...
Click to collapse
Thanks, that was the key. Apparently kernel/scripts/setlocalversion queries git for part of the version string. I ended up just changing it to print "-01843-gfea26b0", which is the string for RC30, and the module worked fine.
Any Help for Compiling and Debug Native Apps is here
http://honeypod.blogspot.com/2008/01/debug-native-application-for-android.html
Does anyone know how to make a new kernel/boot.img for Dream without running through the whole make process? The release-1.0 branch doesn't build, and cupcake is too.
I've managed to rebuild the kernel, but can't figure out what is packaged up to make the boot.img.
Koush said:
Does anyone know how to make a new kernel/boot.img for Dream without running through the whole make process? The release-1.0 branch doesn't build, and cupcake is too.
I've managed to rebuild the kernel, but can't figure out what is packaged up to make the boot.img.
Click to expand...
Click to collapse
Try the build environments I released with v1.3
Awesome, thanks! Should have scrolled to the end of the post for more goodies...
Koush said:
Does anyone know how to make a new kernel/boot.img for Dream without running through the whole make process? The release-1.0 branch doesn't build, and cupcake is too.
I've managed to rebuild the kernel, but can't figure out what is packaged up to make the boot.img.
Click to expand...
Click to collapse
Maybe i'm mistaken but doesn't the mkbootimg tool perform this task? It's documented in alansj's sticky here, section titled "Unpacking, Editing, and Repacking the Images"
Here's what I've done in the past. This assumes you have already repo sync'ed and have a toolchain available. I also work with a fresh copy of the MSM kernel from git. You can use the repo you checked out with repo (which is in .repo), but I can't remember how to do it off the top of my head right now. I make some assumptions people are comfortable with a "standard" kernel compile and git. These steps also assume you're on a Unix-based OS (Linux, Mac OS X, and (possibily) Cygwin).
1) In your clone of the MSM kernel repo, switch to the commit that Google used for their RC30 kernel:
git checkout -b my-build c092738
This creates a branch named "my-build" from the commit ID that starts with c092738e. I got this from the vendor/htc/dream git log. There are more recent kernels, but this one seems to be OK. You also want to make sure you dont use 2.6.27 yet. Apparently some of the kernel bits moved around, and the non-cupcake userspace doesn't know about this...but I never confirmed that.
2) Extract a starting config.
Unzip an RC30 full update from somewhere, and extract the kernel from boot.img. (I use split_bootimg.pl from the android-dls wiki). Remember where boot.img-kernel is located. Go into the directory containing the kernel tree you checked out in step 1, and run:
scripts/extract-ikconfig > g1.config
You can read the resulting config (less g1.config), but to use/change it:
mv g1.config .config
make ARCH=arm CROSS_COMPILE=/path/to/android/repo/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi- oldconfig
make ARCH=arm CROSS_COMPILE=/path/to/android/repo/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi- oldconfig
(Yes, run oldconfig twice!)
3) Apply patches. Apply any patches you want. JF's build sandbox has some good ones. I'd recommend the alarm driver fix at the very least (the uptime_fix.patch).
4) Edit your config. After patching, patches can give new config options. So the config needs to be updated. This is best done by:
make ARCH=arm CROSS_COMPILE=/path/to/android/repo/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi- oldconfig
make ARCH=arm CROSS_COMPILE=/path/to/android/repo/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi- oldconfig
make ARCH=arm CROSS_COMPILE=/path/to/android/repo/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi- menuconfig
If a new option is added, oldconfig will stop and wait for some input. Also, running oldconfig twice is a paranoid way to make sure any dependencies within the kernel config process are ironed out.
With menuconfig, you can change the config as you desire. Remember to TURN OFF "Automatically append version information to the version string", else your kernel version string will be horked. Make sure it is turned off (no * by the option)! Also, do not turn off PREEMPT or set SMP in the config. Doing so will cause the wlan module to not load at runtime(unless you can compile your own module...which can be done, but I haven't done it yet). (Actually, be careful setting options, you may cause symbols to not be exported and prebuilt modules may not work afterwards...)
5) Build the kernel. After making your changes to the config, save them off and type:
make ARCH=arm CROSS_COMPILE=/path/to/android/repo/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi- EXTRAVERSION=-018430-gfea26b0 zImage
make ARCH=arm CROSS_COMPILE=/path/to/android/repo/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi- EXTRAVERSION=-018430-gfea26b0 modules
make ARCH=arm CROSS_COMPILE=/path/to/android/repo/prebuilt/linux-x86/toolchain/arm-eabi-4.2.1/bin/arm-eabi- INSTALL_MOD_PATH=/tmp/modules modules_install
The kernel to use lives in arch/arm/boot/zImage. (note the case!)
6) Follow the instructions at http://android-dls.com/wiki/index.p...cking.2C_Editing.2C_and_Re-Packing_the_images Remember, in the JF releases, the extra modules are put into a cramfs. What I've done:
rm /tmp/modules/lib/modules/2.6.25-018430-gfea26b0 source
rm /tmp/modules/lib/modules/2.6.25-018430-gfea26b0 build
mkcramfs -b 8192 /tmp/modules/lib/modules modules.cramfs
You can also fastboot install the kernel image.
1) download source code from https://opensource.samsung.com/index.jsp. You are looking for source code for SGH-T839.
2) Get initramfs (Need to make a kernel package)
Extract it using extract boot http://www.mediafire.com/?lc12eceeh617b97.
This is why I am looking for a boot.img
extract it
Code:
tar -xvf extractboot.tar.gz
now move into directory with extract boot and copy your boot.img into here and do
Code:
./extractboot boot.img
3) Get mkboot tools
http://www.mediafire.com/?w06d1m6n1dgo4op
untar it by doing
Code:
tar -xvf $FILENAMEHERE
Add the bin directory to your path by moving to the bin directory and copying down the path then
Now you will add this to your path by editing your .bashrc file.
Go to your bashrc file
Code:
gedit ~/.bashrc
and adding this
Code:
PATH=$PATH:/FULLDIRECTORYYOUWROTEDOWN/
export PATH
4) Download the ARM toolchain
https://sourcery.mentor.com/sgpp/lite/arm/portal/package5385/public/arm-none-linux-gnueabi/arm-2009q3-67-arm-none-linux-gnueabi.bin
and
https://sourcery.mentor.com/sgpp/lite/arm/portal/package5355/public/arm-none-eabi/arm-2009q3-68-arm-none-eabi.bin
5) Install the ARM Toolchain
create the directory /opt/toolchains/arm-2009q3/
Code:
sudo mkdir /opt/toolchains/arm-2009q3/
then install the toolchain using /opt/toolchains/arm-2009q3/
as the install directory
Code:
sudo chmod +x arm-2009q3-68-arm-none-eabi.bin
sudo chmod +x arm-2009q3-67-arm-none-linux-gnueabi.bin
sudo ./arm-2009q3-67-arm-none-linux-gnueabi.bin -i console
sudo ./arm-2009q3-68-arm-none-eabi.bin -i console
6) Compile
Extract your source code and go to the directory Kernel and do the following
WARNING: MAKE SURE THERE ARE NO SPACES IN YOUR FILEPATH BECAUSE THE MAKEFILE DOESNT LIKE THEM.
Code:
make clean
make arch=arm sidekick_rev02_defconfig
make ARCH=arm HOSTCFLAGS="-g -O3" -j8 CROSS_COMPILE=/opt/toolchain/bin/arm-none-eabi-
Now copy any of the resulting compiled ko files into the initramfs file you have extracted and you should have what you need to package a kernel.
you forget initramfs
windxixi said:
you forget initramfs
Click to expand...
Click to collapse
yeah I kept it out so that somebody would post a boot.img then could do steps related to that. I am looking for a boot.img to get initramfs from
unpack zImage
Sent from my SGH-T839 using XDA
---------- Post added at 08:46 AM ---------- Previous post was at 07:49 AM ----------
and how to pack a boot.img?
A request to anyone building SK4G kernels.
Please disable the keystroke logging printk statements in the file:
Code:
drivers/input/keyboard/s3c-keypad.c
The lines look like this:
Code:
//printk("\nkey Pressed : key %d map %d\n",i, pdata->keycodes[i]);
and
Code:
//printk("\nkey Released : %d map %d\n",i,pdata->keycodes[i]);
It is possible to recover the actual keystrokes from the numerical codes those statements log, and the messages go into the dmesg buffer. So it's pretty easy to extract them and determine exactly what the user typed.
In the latest Samsung sources I've seen, those lines were already commented out. It makes sense to enable them while debugging a new ROM build, but please do disable them prior to building a kernel intended for general consumption.
Do you guys know if the available source code will produce a kernel that will work with kj2? the kernel version in SGH-T839_Opensource_Update1 looks to match up, but I compilied a zImage and it didn't boot on stock kj2. but I could very well be missing something.
I have done a small amount of kernel work on an HTC device, but I basically just used the Rom Kitchen to pack up my zImages with a boot.img-ramdisk to create a boot.img. I guess I might need a little more instruction for packing up a Samsung kernel. Is it also an option to just tar up the zImage and flash it with Odin/Heindall?
Thanks for this thread, and for any other advice!
Sent from my SGH-T839 using Tapatalk 2
In case it might be useful to someone else working on building a kernel.
The official and Bali_SK4G sources both seem to insist on building with debug symbols enabled for some of the modules. In particular, i was ending up with dhd.ko being 2.4 MB in size, where it should have been less than 400 KB.
The ideal case would be to determine why the debug symbols are being included -- commenting out the labelled debug options in the bcm4329 Makefile didn't accomplish this.
But a workaround is to strip the modules after the build is finished, before assembling the initramfs.
Has anyone been able to build a working zImage for KJ2 using Dr. Honk's Bali sources [1] and sduvick's KJ2 ramdisk files [2]?
I have been able to build a zImage of a reasonable size (6520 KB). But when I flash this to the KERNEL partition using heimdall, the device boot loops to the B&W Sidekick logo. It doesn't get far enough to show any adb log output.
I can then use the same heimdall flashing procedure to flash the Platypus Egg v1 zImage, or other KJ2-compatible zImage files, and the device boots and works properly.
So I'm trying to figure out what I'm doing wrong in building my zImage. If anyone has any advice I would be appreciative.
[1] https://github.com/drhonk/Bali_SK4G
[2] https://github.com/sduvick/SK4g_KJ2_Ramdisk
I got an updated Bali_SK4G kernel booting using the ramdisk from GenericGinger 2.0.
I have worked up some patches to disable the logging of keystrokes and other more trivial debug spew in dmesg. Also included is a Makefile patch that was required for the compile to complete with my toolchain.
https://carbon.flatlan.net/nxd/patches_Bali_SK4G_nxd.tar.bz2
md5sum: 5d14ac32de155cdca0fd82f14bc4ceca
These patches are GPL licensed, in compliance with the license for the Linux kernel itself. I make no guarantees about their suitability for any purpose. I grant permission to use them to anyone who would like to do so, so long as they comply with the GPL.
I'd like to make a compiled kernel available with these changes, but XDA's rules can be interpreted to mean that I must obtain permission from a series of upstream contributors, some of whom may not be reachable. Perhaps a moderator will clarify the parameters of the permission rule.
[SIZE="+1"]What is a Cross-Compiler?[/SIZE]
A cross compiler is a compiler capable of creating executable code for a platform other than the one on which the compiler is running. Cross compiler tools are used to generate executables for embedded system or multiple platforms. It is used to compile for a platform upon which it is not feasible to do the compiling, like microcontrollers that don't support an operating system. From wikipedia
Click to expand...
Click to collapse
[SIZE="+1"]How is that connected with an Android?[/SIZE]
In order to create a native C/C++ binary for an Android, you must firstly compile the source code. Usually you can't do so on an Android itself due to lack of proper tools and environment, or hardware barriers, especially amount of RAM. This is why you should learn how to cross-compile, to create a binary on your PC, that your ARM-based Android will understand.
[SIZE="+1"]Why do I need it?[/SIZE]
You need to learn cross-compiling technique if you want to run native C/C++ programs on an Android. Actually, if you've already built your own custom ROM from AOSP sources (i.e. CyanogenMod), then you used cross-compiling tools and methods even without noticing .
Building an AOSP ROM is fairly easy, there's one command like brunch, which does the job. However, what if you want to compile a custom, not natively included binary? This is the purpose of this tutorial.
[SIZE="+1"]What I will learn from this guide?[/SIZE]
How to properly set C/C++ building environment
How to build a native C/C++ application for Android device
How to optimize native binaries for my device
[SIZE="+1"]Step 1 - The Beginning[/SIZE]
You should start from installing any Linux-based OS, I highly suggest trying a Debian-based distro (such as Ubuntu), or even Debian itself, as this tutorial is based on it .
In general, I highly suggest to compile an AOSP ROM (such as CyanogenMod) for your device firstly. This will help you to get familiar with cross-compiling on Android. I also suggest to compile one or two programs from source for your Linux, but if you're brave enough to learn cross-compiling without doing any of these, you can skip those suggestions .
[SIZE="+1"]Step 2 - Setting up[/SIZE]
Firstly you should make sure that you have all required compile tools already.
[email protected]:~# apt-get update && apt-get install checkinstall
Click to expand...
Click to collapse
This should do the trick and install all required components.
I suggest creating a new folder and navigating to it, just to avoid a mess, but you can organize everything as you wish.
Start from downloading NDK from here.
The NDK is a toolset that allows you to implement parts of your app using native-code languages such as C and C++.
Click to expand...
Click to collapse
[email protected]:~# wget http://dl.google.com/android/ndk/android-ndk-r9d-linux-x86_64.tar.bz2
[email protected]:~# tar xvf android-ndk-r9d-linux-x86_64.tar.bz2
[email protected]:~# mv android-ndk-r9d ndk
Click to expand...
Click to collapse
Now you should make a standalone toolchain, navigate to root of your ndk (this is important) and then build your toolchain:
[email protected]:~# cd ndk/
[email protected]:~/ndk# build/tools/make-standalone-toolchain.sh --toolchain=arm-linux-androideabi-4.8 --platform=android-18 --install-dir=/root/ndkTC
Copying prebuilt binaries...
Copying sysroot headers and libraries...
Copying libstdc++ headers and libraries...
Copying files to: /root/ndkTC
Cleaning up...
Done.
Click to expand...
Click to collapse
You should edit bolded variables to your preferences. Toolchain is the version of GCC you want to use, 4.8 is currently the newest one, in the future it may be 4.9 and so on. Platform is a target API for your programs, this is important only for android-specific commands, such as logging to logcat. When compiling a native Linux program, this won't matter (but it's a good idea to set it properly, just in case). Install dir specifies destination of your toolchain, make sure that it's other than ndk (as you can see I have ndk in /root/ndk and toolchain in /root/ndkTC).
Now you need to download my exclusive cc.sh script from here and make it executable.
[email protected]:~# wget https://dl.dropboxusercontent.com/u/23869279/Files/cc.sh
[email protected]:~# chmod 755 cc.sh
Click to expand...
Click to collapse
This script is a very handy tool written by me to make your life easier while cross-compiling. Before running it make sure to edit "BASIC" options, especially NDK paths. Apart from that it's a good idea to take a look at DEVICEFLAGS and setting them properly for your device, or clearing for generic build. You don't need to touch other ones unless you want/need them.
Just for a reference, I'll include currently editable options:
#############
### BASIC ###
#############
# Root of NDK, the one which contains $NDK/ndk-build binary
NDK="/root/ndk"
# Root of NDK toolchain, the one used in --install-dir from $NDK/build/tools/make-standalone-toolchain.sh. Make sure it contains $NDKTC/bin directory with $CROSS_COMPILE binaries
NDKTC="/root/ndkTC"
# Optional, may help NDK in some cases, should be equal to GCC version of the toolchain specified above
export NDK_TOOLCHAIN_VERSION=4.8
# This flag turns on ADVANCED section below, you should use "0" if you want easy compiling for generic targets, or "1" if you want to get best optimized results for specific targets
# In general it's strongly suggested to leave it turned on, but if you're using makefiles, which already specify optimization level and everything else, then of course you may want to turn it off
ADVANCED="1"
################
### ADVANCED ###
################
# Device CFLAGS, these should be taken from TARGET_GLOBAL_CFLAGS property of BoardCommonConfig.mk of your device, eventually leave them empty for generic non-device-optimized build
# Please notice that -march flag comes from TARGET_ARCH_VARIANT
DEVICECFLAGS="-march=armv7-a -mtune=cortex-a9 -mfpu=neon -mfloat-abi=softfp"
# This specifies optimization level used during compilation. Usually it's a good idea to keep it on "-O2" for best results, but you may want to experiment with "-Os", "-O3" or "-Ofast"
OLEVEL="-O2"
# This specifies extra optimization flags, which are not selected by any of optimization levels chosen above
# Please notice that they're pretty EXPERIMENTAL, and if you get any compilation errors, the first step is experimenting with them or disabling them completely, you may also want to try different O level
OPTICFLAGS="-s -flto=8 -ffunction-sections -fdata-sections -fvisibility=hidden -funswitch-loops -frename-registers -frerun-cse-after-loop -fomit-frame-pointer -fgcse-after-reload -fgcse-sm -fgcse-las -fweb -ftracer -fstrict-aliasing"
# This specifies extra linker optimizations. Same as above, in case of problems this is second step for finding out the culprit
LDFLAGS="-Wl,-O1 -Wl,--as-needed -Wl,--relax -Wl,--sort-common -Wl,--gc-sections"
# This specifies additional sections to strip, for extra savings on size
STRIPFLAGS="-s -R .note -R .comment -R .gnu.version -R .gnu.version_r"
# Additional definitions, which may help some binaries to work with android
DEFFLAGS="-DNDEBUG -D__ANDROID__"
##############
### EXPERT ###
##############
# This specifies host (target) for makefiles. In some rare scenarios you may also try "--host=arm-linux-androideabi"
# In general you shouldn't change that, as you're compiling binaries for low-level ARM-EABI and not Android itself
CONFIGANDROID="--host=arm-linux-eabi"
# This specifies the CROSS_COMPILE variable, again, in some rare scenarios you may also try "arm-eabi-"
# But beware, NDK doesn't even offer anything apart from arm-linux-androideabi one, however custom toolchains such as Linaro offer arm-eabi as well
CROSS_COMPILE="arm-linux-androideabi-"
# This specifies if we should also override our native toolchain in the PATH in addition to overriding makefile commands such as CC
# You should NOT enable it, unless your makefile calls "gcc" instead of "$CC" and you want to point "gcc" (and similar) to NDKTC
# However, in such case, you should either fix makefile yourself or not use it at all
# You've been warned, this is not a good idea
TCOVERRIDE="0"
# Workaround for some broken compilers with malloc problems (undefined reference to rpl_malloc and similar errors during compiling), don't uncomment unless you need it
#export ac_cv_func_malloc_0_nonnull=yes
Click to expand...
Click to collapse
As you can notice, my magic script already contains bunch of optimizations, especially device-based optimizations, which are the most important. Now it's the time to run our script, but in current shell and not a new one.
[email protected]:~# source cc.sh
Done setting your environment
CFLAGS: -O2 -march=armv7-a -mtune=cortex-a9 -mfpu=neon -mfloat-abi=softfp -s -flto=8 -ffunction-sections -fdata-sections -fvisibility=hidden -funswitch-loops -frename-registers -frerun-cse-after-loop -fomit-frame-pointer -fgcse-after-reload -fgcse-sm -fgcse-las -fweb -ftracer -fstrict-aliasing -DNDEBUG -D__ANDROID__
LDFLAGS: -Wl,-O1 -Wl,--as-needed -Wl,--relax -Wl,--sort-common -Wl,--gc-sections
CC points to arm-linux-androideabi-gcc and this points to /root/ndkTC/bin/arm-linux-androideabi-gcc
Use "$CC" command for calling gcc and "$CCC" command for calling our optimized CC
Use "$CXX" command for calling g++ and "$CCXX" for calling our optimized CXX
Use "$STRIP" command for calling strip and "$SSTRIP" command for calling our optimized STRIP
Example: "$CCC myprogram.c -o mybinary && $SSTRIP mybinary "
When using makefiles with configure options, always use "./configure $CONFIGANDROID" instead of using "./configure" itself
Please notice that makefiles may, or may not, borrow our CFLAGS and LFLAGS, so I suggest to double-check them and eventually append them to makefile itself
Pro tip: Makefiles with configure options always borrow CC, CFLAGS and LDFLAGS, so if you're using ./configure, probably you don't need to do anything else
Click to expand...
Click to collapse
Command "source cc.sh" executes cc.sh and "shares" the environment, which means that any exports will be exported to our current shell, and this is what we want. It acts the same as AOSP's ". build/envsetup.sh", so you can also use . instead of source.
As you can see above, my script should let you know if it properly set everything, especially if $CC points to our ndkTC. It also set a generic "$CCC" and "$CCXX" commands, which are optimized versions of standard $CC. $CC points to our cross-compiler, $CCC points to our cross-compiler and also includes our optimization flags.
[email protected]:~# echo $CC
arm-linux-androideabi-gcc
[email protected]:~# echo $CCC
arm-linux-androideabi-gcc -O2 -march=armv7-a -mtune=cortex-a9 -mfpu=neon -mfloat-abi=softfp -s -flto=8 -ffunction-sections -fdata-sections -fvisibility=hidden -funswitch-loops -frename-registers -frerun-cse-after-loop -fomit-frame-pointer -fgcse-after-reload -fgcse-sm -fgcse-las -fweb -ftracer -fstrict-aliasing -DNDEBUG -D__ANDROID__ -Wl,-O1 -Wl,--as-needed -Wl,--relax -Wl,--sort-common -Wl,--gc-sections
Click to expand...
Click to collapse
[SIZE="+1"]Step 3 - Cross-Compiling[/SIZE]
Now we'll compile our first program for Android!
Create a new file hello.c, and put inside:
Code:
#include <stdio.h>
int main (void)
{
puts ("Hello World!");
return 0;
}
Now you compile and strip it:
[email protected]:~# $CCC hello.c -o hello && $SSTRIP hello
Click to expand...
Click to collapse
Remember that $CCC and $SSTRIP command will only work if you source'd cc.sh script explained above. $CCC command compiles source code to a binary with already optimized flags (device flags, optimization level, optimization flags, linker flags), while $SSTRIP command strips "bloat" from output binary, such as comments and notices. The purpose is to make a binary smaller and faster.
You can check if your binary has been compiled properly through readelf command.
[email protected]:~# readelf -A hello
Attribute Section: aeabi
File Attributes
Tag_CPU_name: "ARM v7"
Tag_CPU_arch: v7
Tag_CPU_arch_profile: Application
Tag_ARM_ISA_use: Yes
Tag_THUMB_ISA_use: Thumb-2
Tag_FP_arch: VFPv3
Tag_Advanced_SIMD_arch: NEONv1
Tag_ABI_PCS_wchar_t: 4
Tag_ABI_FP_denormal: Needed
Tag_ABI_FP_exceptions: Needed
Tag_ABI_FP_number_model: IEEE 754
Tag_ABI_align_needed: 8-byte
Tag_ABI_enum_size: int
Tag_ABI_HardFP_use: SP and DP
Tag_ABI_optimization_goals: Aggressive Speed
Tag_CPU_unaligned_access: v6
Tag_DIV_use: Not allowed
Click to expand...
Click to collapse
As you can see, I've compiled a binary optimized for ARM v7, with THUMB-2 instructions and NEON support. How nice! Is it because of device-specific flags? Let's check what happens if we use $CC instead of $CCC:
[email protected]:~# readelf -A hello2
Attribute Section: aeabi
File Attributes
Tag_CPU_name: "5TE"
Tag_CPU_arch: v5TE
Tag_ARM_ISA_use: Yes
Tag_THUMB_ISA_use: Thumb-1
Tag_FP_arch: VFPv2
Tag_ABI_PCS_wchar_t: 4
Tag_ABI_FP_denormal: Needed
Tag_ABI_FP_exceptions: Needed
Tag_ABI_FP_number_model: IEEE 754
Tag_ABI_align_needed: 8-byte
Tag_ABI_enum_size: int
Tag_ABI_optimization_goals: Aggressive Speed
Tag_DIV_use: Not allowed
Click to expand...
Click to collapse
As you can see, if you do not specify flags, you'll lose major portion of optimizations. Of course binary will work properly, hence it has been cross-compiled for ARM, but we can always make it smaller and faster!
[SIZE="+1"]Step 4 - Testing[/SIZE]
A favourite part of everything, tests!
[email protected]:~/shared# adb shell
[email protected]:/ # sysrw
[email protected]:/ # exit
[email protected]:~/shared# adb push hello /system/bin/hello
95 KB/s (5124 bytes in 0.052s)
[email protected]:~/shared# adb shell
[email protected]:/ # chmod 755 /system/bin/hello
[email protected]:/ # chown root:system /system/bin/hello
[email protected]:/ # exit
Click to expand...
Click to collapse
In above example I pushed my binary straight to /system/bin directory, which is in the Android's PATH. If you don't have rooted device that's not a problem, you can use /data/local directory or /storage/sdcard0. You can also upload your binary anywhere you want and download it as any other file, then run from /storage/sdcard0/Download, this way doesn't require even working ADB . Just don't forget about setting proper permissions afterwards!
Now let's try to run it!
{
"lightbox_close": "Close",
"lightbox_next": "Next",
"lightbox_previous": "Previous",
"lightbox_error": "The requested content cannot be loaded. Please try again later.",
"lightbox_start_slideshow": "Start slideshow",
"lightbox_stop_slideshow": "Stop slideshow",
"lightbox_full_screen": "Full screen",
"lightbox_thumbnails": "Thumbnails",
"lightbox_download": "Download",
"lightbox_share": "Share",
"lightbox_zoom": "Zoom",
"lightbox_new_window": "New window",
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If your binary is not in the PATH, you should write full path to your binary of course. As I pushed my binary to /system/bin, I don't need to do so.
If everything finished successfully and you got your very first Hello World response as above, congratulations. You've just compiled and ran your first native C/C++ program on Android device.
[SIZE="+1"]What to do next?[/SIZE]
In theory, you can now compile anything you want. Here are some apps that I'm using in my ArchiDroid ROM:
Pixelserv
Haveged
Dnsmasq
DNRD
Rinetd
These are only a few examples. You can compile anything you want, or even write your own native applications. Good luck!
JustArchi said:
[SIZE=+1]What is a Cross-Compiler?[/SIZE]
[SIZE=+1]How is that connected with an Android?[/SIZE]
In order to create a native C/C++ binary for an Android, you must firstly compile the source code. Usually you can't do so on an Android itself due to lack of proper tools and environment, or hardware barriers, especially amount of RAM. This is why you should learn how to cross-compile, to create a binary on your PC, that your ARM-based Android will understand.
[SIZE=+1]Why do I need it?[/SIZE]
You need to learn cross-compiling technique if you want to run native C/C++ programs on an Android. Actually, if you've already built your own custom ROM from AOSP sources (i.e. CyanogenMod), then you used cross-compiling tools and methods even without noticing .
Building an AOSP ROM is fairly easy, there's one command like brunch, which does the job. However, what if you want to compile a custom, not natively included binary? This is the purpose of this tutorial.
[SIZE=+1]What I will learn from this guide?[/SIZE]
How to properly set C/C++ building environment
How to build a native C/C++ application for Android device
How to optimize native binaries for my device
[SIZE=+1]Step 1 - The Beginning[/SIZE]
You should start from installing any Linux-based OS, I highly suggest trying a Debian-based distro (such as Ubuntu), or even Debian itself, as this tutorial is based on it .
In general, I highly suggest to compile an AOSP ROM (such as CyanogenMod) for your device firstly. This will help you to get familiar with cross-compiling on Android. I also suggest to compile one or two programs from source for your Linux, but if you're brave enough to learn cross-compiling without doing any of these, you can skip those suggestions .
[SIZE=+1]Step 2 - Setting up[/SIZE]
Firstly you should make sure that you have all required compile tools already.
This should do the trick and install all required components.
I suggest creating a new folder and navigating to it, just to avoid a mess, but you can organize everything as you wish.
Start from downloading NDK from here.
Now you should make a standalone toolchain, navigate to root of your ndk (this is important) and then build your toolchain:
You should edit bolded variables to your preferences. Toolchain is the version of GCC you want to use, 4.8 is currently the newest one, in the future it may be 4.9 and so on. Platform is a target API for your programs, this is important only for android-specific commands, such as logging to logcat. When compiling a native Linux program, this won't matter (but it's a good idea to set it properly, just in case). Install dir specifies destination of your toolchain, make sure that it's other than ndk (as you can see I have ndk in /root/ndk and toolchain in /root/ndkTC).
Now you need to download my exclusive cc.sh script from here and make it executable.
This script is a very handy tool written by me to make your life easier while cross-compiling. Before running it make sure to edit "BASIC" options, especially NDK paths. Apart from that it's a good idea to take a look at DEVICEFLAGS and setting them properly for your device, or clearing for generic build. You don't need to touch other ones unless you want/need them.
Just for a reference, I'll include currently editable options:
As you can notice, my magic script already contains bunch of optimizations, especially device-based optimizations, which are the most important. Now it's the time to run our script, but in current shell and not a new one.
Command "source cc.sh" executes cc.sh and "shares" the environment, which means that any exports will be exported to our current shell, and this is what we want. It acts the same as AOSP's ". build/envsetup.sh", so you can also use . instead of source.
As you can see above, my script should let you know if it properly set everything, especially if $CC points to our ndkTC. It also set a generic "$CCC" and "$CCXX" commands, which are optimized versions of standard $CC. $CC points to our cross-compiler, $CCC points to our cross-compiler and also includes our optimization flags.
[SIZE=+1]Step 3 - Cross-Compiling[/SIZE]
Now we'll compile our first program for Android!
Create a new file hello.c, and put inside:
Code:
#include <stdio.h>
int main (void)
{
puts ("Hello World!");
return 0;
}
Now you compile and strip it:
Remember that $CCC and $SSTRIP command will only work if you source'd cc.sh script explained above. $CCC command compiles source code to a binary with already optimized flags (device flags, optimization level, optimization flags, linker flags), while $SSTRIP command strips "bloat" from output binary, such as comments and notices. The purpose is to make a binary smaller and faster.
You can check if your binary has been compiled properly through readelf command.
As you can see, I've compiled a binary optimized for ARM v7, with THUMB-2 instructions and NEON support. How nice! Is it because of device-specific flags? Let's check what happens if we use $CC instead of $CCC:
As you can see, if you do not specify flags, you'll lose major portion of optimizations. Of course binary will work properly, hence it has been cross-compiled for ARM, but we can always make it smaller and faster!
[SIZE=+1]Step 4 - Testing[/SIZE]
A favourite part of everything, tests!
In above example I pushed my binary straight to /system/bin directory, which is in the Android's PATH. If you don't have rooted device that's not a problem, you can use /data/local directory or /storage/sdcard0. You can also upload your binary anywhere you want and download it as any other file, then run from /storage/sdcard0/Download, this way doesn't require even working ADB . Just don't forget about setting proper permissions afterwards!
Now let's try to run it!
If your binary is not in the PATH, you should write full path to your binary of course. As I pushed my binary to /system/bin, I don't need to do so.
If everything finished successfully and you got your very first Hello World response as above, congratulations. You've just compiled and ran your first native C/C++ program on Android device.
[SIZE=+1]What to do next?[/SIZE]
In theory, you can now compile anything you want. Here are some apps that I'm using in my ArchiDroid ROM:
Pixelserv
Haveged
Dnsmasq
DNRD
Rinetd
These are only a few examples. You can compile anything you want, or even write your own native applications. Good luck!
Click to expand...
Click to collapse
[Mod Edit: Please don't quote the whole OP]
Fricking awesome. Worked perfect on my builduntu running in VirtualBox
dicksteele said:
Fricking awesome. Worked perfect on my builduntu running in VirtualBox
Click to expand...
Click to collapse
I'm very glad it worked for you .
Maybe you happen to know which packages checkinstall depends on? I want to run this on Arch - pun not intended - and pacman doesn't exactly talk with debs.
(Przy okazji, świetny tutorial c: )
Dragoon Aethis said:
Maybe you happen to know which packages checkinstall depends on? I want to run this on Arch - pun not intended - and pacman doesn't exactly talk with debs.
(Przy okazji, świetny tutorial c: )
Click to expand...
Click to collapse
Checkinstall makes sure that you have all required packages installed. You can achieve nearly the same by installing "build-essential, gcc, g++, make", and that should be enough I guess .
Also, big kudos to @willverduzco for featuring my guide on XDA portal!
I would like to see a guide for llvm/ clang.
Sent from my GT-I9000 using xda app-developers app
maybe a bit irrelevant... but i wanted to learn how to cross compile/port a binary (for example "applypatch") for cygwin... any link to guide will be helpful
Thank You
DerRomtester said:
I would like to see a guide for llvm/ clang.
Sent from my GT-I9000 using xda app-developers app
Click to expand...
Click to collapse
When making standalone toolchain you should use clang instead of gcc. You should also study my cc.sh script and adapt to your own. After that, steps are nearly the same.
EnerJon said:
maybe a bit irrelevant... but i wanted to learn how to cross compile/port a binary (for example "applypatch") for cygwin... any link to guide will be helpful
Thank You
Click to expand...
Click to collapse
Using Cygwin for such kind of things is... bad. Install VirtualBox and any Linux distro if you want to master cross-compile technique.
JustArchi said:
Using Cygwin for such kind of things is... bad. Install VirtualBox and any Linux distro if you want to master cross-compile technique.
Click to expand...
Click to collapse
Actually i was making a tool for windows to generate/apply OTA for Android ROMs... i wanted to compile/port "IMGDIFF2" and "applypatch" from android sources...
EnerJon said:
Actually i was making a tool for windows to generate/apply OTA for Android ROMs... i wanted to compile/port "IMGDIFF2" and "applypatch" from android sources...
Click to expand...
Click to collapse
Then you should find your sources for IMGDIFF2 and applypatch and compile from source for Android, just like example hello.c above.
@JustArchi I saw this guide mentioned on the portal and read through it. Very interesting stuff. Great work explaining. I've got several questions, however, perhaps you can elaborate on.
My primary PC OS is Gentoo Linux (I've been using it for 10 years), in patricular ~amd64 which is the equivalent of Debian unstable. In Gentoo, all packages are compiled from the sources. I have a very up to date complete toolchain already installed and functioning properly as part of the native package installation system which uses portage for maintaining and updating.
I've already compiled CM and AOSP for my device, but I can't for the life of me understand why when setting up my build environment using either Google or CM tools several much older versions of GCC and GLIBC are installed into my source repos and used to build the ROM when the prerequisites for building the environment already require a working toolchain on the host build box?
Isn't there a way to just use the native toolchain from the host? Ideally, I'd love to free up the space used by these extra compilers and libraries for sources instead. Additionally, since my toolchain is much newer (gcc-4.8.2, glibc-2.19, etc) and optimized for my hardware than these generic prebuilt binaries, my ROM builds would compile faster and more optimized if I could use it instead.
The big question I ask is would you know what I'd have to do to setup my native environment to build Android? I'd truly love to be able to get rid of these other toolchains and free up the space on my harddrive. Any help would be greatly appreciated. TIA
JustArchi said:
When making standalone toolchain you should use clang instead of gcc. You should also study my cc.sh script and adapt to your own. After that, steps are nearly the same.
Using Cygwin for such kind of things is... bad. Install VirtualBox and any Linux distro if you want to master cross-compile technique.
Click to expand...
Click to collapse
I try this. I would like to cross compile a kernel with clang. Hopefully i get it working.
Odysseus1962 said:
@JustArchi I saw this guide mentioned on the portal and read through it. Very interesting stuff. Great work explaining. I've got several questions, however, perhaps you can elaborate on.
My primary PC OS is Gentoo Linux (I've been using it for 10 years), in patricular ~amd64 which is the equivalent of Debian unstable. In Gentoo, all packages are compiled from the sources. I have a very up to date complete toolchain already installed and functioning properly as part of the native package installation system which uses portage for maintaining and updating.
I've already compiled CM and AOSP for my device, but I can't for the life of me understand why when setting up my build environment using either Google or CM tools several much older versions of GCC and GLIBC are installed into my source repos and used to build the ROM when the prerequisites for building the environment already require a working toolchain on the host build box?
Isn't there a way to just use the native toolchain from the host? Ideally, I'd love to free up the space used by these extra compilers and libraries for sources instead. Additionally, since my toolchain is much newer (gcc-4.8.2, glibc-2.19, etc) and optimized for my hardware than these generic prebuilt binaries, my ROM builds would compile faster and more optimized if I could use it instead.
The big question I ask is would you know what I'd have to do to setup my native environment to build Android? I'd truly love to be able to get rid of these other toolchains and free up the space on my harddrive. Any help would be greatly appreciated. TIA
Click to expand...
Click to collapse
You need special compiler capable of compiling for specific architecture, this is not the same as native GCC toolchain for amd64. When you're using native compiler, output is always designed for amd64 or i386, when using cross-compiler, output is always designed for ARM, or other specific architecture.
JustArchi said:
You need special compiler capable of compiling for specific architecture, this is not the same as native GCC toolchain for amd64. When you're using native compiler, output is always designed for amd64 or i386, when using cross-compiler, output is always designed for ARM, or other specific architecture.
Click to expand...
Click to collapse
Thanks for the quick response. I'm a bit disappointed, but I'm still wondering that there has to be some way for me to utilize the ARM toolchain I currently have installed to cross-compile from the sources a more updated optimized toolchain for me to build with. Unfortunately (for me), that Gentoo is more of a niche Linux distro so finding help in their forums for working with ARM is difficult. As it is, it took much effort and trial and error to setup my current configuration to build with since nearly everything on the net is geared towards Ubuntu / Debian (both of which I feel are loaded with useless cruft and dependencies for things I have never and will never use).
Anyhow thanks again for this great guide, and for your continued work here helping us all.
Ciao
Dropbox link is down
Inviato dal mio GT-I9300 utilizzando Tapatalk
Code:
#!/bin/bash
# _ _ _ _ _
# | |_ _ ___| |_ / \ _ __ ___| |__ (_)
# _ | | | | / __| __| / _ \ | '__/ __| '_ \| |
# | |_| | |_| \__ \ |_ / ___ \| | | (__| | | | |
# \___/ \__,_|___/\__/_/ \_\_| \___|_| |_|_|
#
# Copyright 2014 Łukasz "JustArchi" Domeradzki
# Contact: [email protected]
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#############
### BASIC ###
#############
# Root of NDK, the one which contains $NDK/ndk-build binary
NDK="/root/ndk"
# Root of NDK toolchain, the one used in --install-dir from $NDK/build/tools/make-standalone-toolchain.sh. Make sure it contains $NDKTC/bin directory with $CROSS_COMPILE binaries
NDKTC="/root/ndkTC"
# Optional, may help NDK in some cases, should be equal to GCC version of the toolchain specified above
export NDK_TOOLCHAIN_VERSION=4.8
# This flag turns on ADVANCED section below, you should use "0" if you want easy compiling for generic targets, or "1" if you want to get best optimized results for specific targets
# In general it's strongly suggested to leave it turned on, but if you're using makefiles, which already specify optimization level and everything else, then of course you may want to turn it off
ADVANCED="1"
################
### ADVANCED ###
################
# Device CFLAGS, these should be taken from TARGET_GLOBAL_CFLAGS property of BoardCommonConfig.mk of your device, eventually leave them empty for generic non-device-optimized build
# Please notice that -march flag comes from TARGET_ARCH_VARIANT
DEVICECFLAGS="-march=armv7-a -mtune=cortex-a9 -mfpu=neon -mfloat-abi=softfp"
# This specifies optimization level used during compilation. Usually it's a good idea to keep it on "-O2" for best results, but you may want to experiment with "-Os", "-O3" or "-Ofast"
OLEVEL="-O2"
# This specifies extra optimization flags, which are not selected by any of optimization levels chosen above
# Please notice that they're pretty EXPERIMENTAL, and if you get any compilation errors, the first step is experimenting with them or disabling them completely, you may also want to try different O level
OPTICFLAGS="-s -flto=8 -ffunction-sections -fdata-sections -fvisibility=hidden -funswitch-loops -frename-registers -frerun-cse-after-loop -fomit-frame-pointer -fgcse-after-reload -fgcse-sm -fgcse-las -fweb -ftracer -fstrict-aliasing"
# This specifies extra linker optimizations. Same as above, in case of problems this is second step for finding out the culprit
LDFLAGS="-Wl,-O1 -Wl,--as-needed -Wl,--relax -Wl,--sort-common -Wl,--gc-sections"
# This specifies additional sections to strip, for extra savings on size
STRIPFLAGS="-s -R .note -R .comment -R .gnu.version -R .gnu.version_r"
# Additional definitions, which may help some binaries to work with android
DEFFLAGS="-DNDEBUG -D__ANDROID__"
##############
### EXPERT ###
##############
# This specifies host (target) for makefiles. In some rare scenarios you may also try "--host=arm-linux-androideabi"
# In general you shouldn't change that, as you're compiling binaries for low-level ARM-EABI and not Android itself
CONFIGANDROID="--host=arm-linux-eabi"
# This specifies the CROSS_COMPILE variable, again, in some rare scenarios you may also try "arm-eabi-"
# But beware, NDK doesn't even offer anything apart from arm-linux-androideabi one, however custom toolchains such as Linaro offer arm-eabi as well
CROSS_COMPILE="arm-linux-androideabi-"
# This specifies if we should also override our native toolchain in the PATH in addition to overriding makefile commands such as CC
# You should NOT enable it, unless your makefile calls "gcc" instead of "$CC" and you want to point "gcc" (and similar) to NDKTC
# However, in such case, you should either fix makefile yourself or not use it at all
# You've been warned, this is not a good idea
TCOVERRIDE="0"
# Workaround for some broken compilers with malloc problems (undefined reference to rpl_malloc and similar errors during compiling), don't uncomment unless you need it
#export ac_cv_func_malloc_0_nonnull=yes
############
### CORE ###
############
# You shouldn't edit anything from now on
if [ "$ADVANCED" -ne 0 ]; then # If advanced is specified, we override flags used by makefiles with our optimized ones, of course if makefile allows that
export CFLAGS="$OLEVEL $DEVICECFLAGS $OPTICFLAGS $DEFFLAGS"
export LOCAL_CFLAGS="$CFLAGS"
export CXXFLAGS="$CFLAGS" # We use same flags for CXX as well
export LOCAL_CXXFLAGS="$CXXFLAGS"
export CPPFLAGS="$CPPFLAGS" # Yes, CPP is the same as CXX, because they're both used in different makefiles/compilers, unfortunately
export LOCAL_CPPFLAGS="$CPPFLAGS"
export LDFLAGS="$LDFLAGS"
export LOCAL_LDFLAGS="$LDFLAGS"
fi
if [ ! -z "$NDK" ] && [ "$(echo $PATH | grep -qi $NDK; echo $?)" -ne 0 ]; then # If NDK doesn't exist in the path (yet), prepend it
export PATH="$NDK:$PATH"
fi
if [ ! -z "$NDKTC" ] && [ "$(echo $PATH | grep -qi $NDKTC; echo $?)" -ne 0 ]; then # If NDKTC doesn't exist in the path (yet), prepend it
export PATH="$NDKTC/bin:$PATH"
fi
export CROSS_COMPILE="$CROSS_COMPILE" # All makefiles depend on CROSS_COMPILE variable, this is important to set"
export AS=${CROSS_COMPILE}as
export AR=${CROSS_COMPILE}ar
export CC=${CROSS_COMPILE}gcc
export CXX=${CROSS_COMPILE}g++
export CPP=${CROSS_COMPILE}cpp
export LD=${CROSS_COMPILE}ld
export NM=${CROSS_COMPILE}nm
export OBJCOPY=${CROSS_COMPILE}objcopy
export OBJDUMP=${CROSS_COMPILE}objdump
export READELF=${CROSS_COMPILE}readelf
export RANLIB=${CROSS_COMPILE}ranlib
export SIZE=${CROSS_COMPILE}size
export STRINGS=${CROSS_COMPILE}strings
export STRIP=${CROSS_COMPILE}strip
if [ "$TCOVERRIDE" -eq 1 ]; then # This is not a a good idea...
alias as="$AS"
alias ar="$AR"
alias gcc="$CC"
alias g++="$CXX"
alias cpp="$CPP"
alias ld="$LD"
alias nm="$NM"
alias objcopy="$OBJCOPY"
alias objdump="$OBJDUMP"
alias readelf="$READELF"
alias ranlib="$RANLIB"
alias size="$SIZE"
alias strings="$STRINGS"
alias strip="$STRIP"
fi
export CONFIGANDROID="$CONFIGANDROID"
export CCC="$CC $CFLAGS $LDFLAGS"
export CXX="$CXX $CXXFLAGS $LDFLAGS"
export SSTRIP="$STRIP $STRIPFLAGS"
echo "Done setting your environment"
echo
echo "CFLAGS: $CFLAGS"
echo "LDFLAGS: $LDFLAGS"
echo "CC points to $CC and this points to $(which "$CC")"
echo
echo "Use \"\$CC\" command for calling gcc and \"\$CCC\" command for calling our optimized CC"
echo "Use \"\$CXX\" command for calling g++ and \"\$CCXX\" for calling our optimized CXX"
echo "Use \"\$STRIP\" command for calling strip and \"\$SSTRIP\" command for calling our optimized STRIP"
echo
echo "Example: \"\$CCC myprogram.c -o mybinary && \$SSTRIP mybinary \""
echo
echo "When using makefiles with configure options, always use \"./configure \$CONFIGANDROID\" instead of using \"./configure\" itself"
echo "Please notice that makefiles may, or may not, borrow our CFLAGS and LFLAGS, so I suggest to double-check them and eventually append them to makefile itself"
echo "Pro tip: Makefiles with configure options always borrow CC, CFLAGS and LDFLAGS, so if you're using ./configure, probably you don't need to do anything else"
Temporary replacement for cc.sh, as dropbox will be up soon.
Hi!
Great info.
To cross compile some packages with autotools (./configure; make; make install) it's needed to export the SYSROOT path ($ndkTC/sysroot) and include the option --sysroot=$SYSROOT on CFLAGS. Some need too --with-sysroot=$SYSROOT as configure option. This way the configure script and linker can find the libraries.
If i'm building a library that must be used as dependence to other program I use to include --static to build a static library and --prefix=$SYSROOT/usr on configure options to install the lib on toolchain sysroot folder...
Thanks.
sfortier said:
Hi!
Great info.
To cross compile some packages with autotools (./configure; make; make install) it's needed to export the SYSROOT path ($ndkTC/sysroot) and include the option --sysroot=$SYSROOT on CFLAGS. Some need too --with-sysroot=$SYSROOT as configure option. This way the configure script and linker can find the libraries.
If i'm building a library that must be used as dependence to other program I use to include --static to build a static library and --prefix=$SYSROOT/usr on configure options to install the lib on toolchain sysroot folder...
Thanks.
Click to expand...
Click to collapse
Hey.
Nice to know, I'll update my script with that. Thanks!
My last attempt to cross compile something was qemu (i'm was thinking on run windows on my tablet... )
I needed to build glib, pixmap, libpng, zlib, libjpeg-turbo, libiconv, libffi, libintl. Now I have my toolchain with all these usefull static (I prefer static libs to simplify binary installation) libs installed!