I've cross-compiled the bulk of my 32-bit code on my x64 Ubuntu install, but I can't work out how to do the same trick with libcurl.
I've tried many permutations of --host and/or --build i486, x86, etc. but none have helped. I've also tried editing the makefiles to include gcc's -m32 flag manually, but it never shows up when I run them.
What should I be doing?
After you download and extract the libcurl source package, as a root user, run this command for setting up the build environment.
configure --host=i686-pc-linux-gnu CFLAGS=-m32 CC=/usr/bin/gcc
followed by
make
you can find the libs under ./lib/.libs/libcurl.so from where you ran the make command.
if you dont find /usr/bin/gcc, you will have to install gcc for 32-bit cross compilation env in a 64-bit machine.
It would help if you gave us an error message. I've had issues on Ubuntu x64 systems compiling 32-bit code with 'ld' errors.. I solved it by adding LDEMULATION=elf_i386 to my environment.
Related
I am trying to compile the GNU binutils for PowerPc on my x86-64 Pc. I'm not trying to cross compile them (got the cross compiler version from the AUR), I'm trying to compile the on my pc to use them on the other(It has no network etc just an SD-card). Anyways I have downloaded the tar file and tried to run ./configure but I wasn't sure what options to use and couldn't any proper documentation... For example what to I need to set $CC to the powerpc-linux-gnu-gcc compiler or do i need to set this as $CC_FOR_TARGET or both idk. I found out --prefix is the output output folder but idk anything else. Pl help
Cross compiling can be difficult if you are not familiar with the process. I'd recommend Debian and Ubuntu as they have a very good set of cross compilers prepackaged you can get with apt install gcc-powerpc64le-linux-gnu.
Alternatively, you can download cross compilers from: https://toolchains.bootlin.com/
There is information about the config options available by running ./configure --help
The relevant option in this situation is:
--host=HOST cross-compile to build programs to run on HOST [BUILD]
For 32bit ppc:
./configure --host=powerpc-linux-gnu
I need to use tools that depend on clang on a Unix machine I remote onto at work. Anything I install is locally installed onto ~/local. I do not have root permissions.
/usr is pretty outdated, with gcc being at version 4.4.7. clang requires gcc 4.7+
I read on linux from scratch that a gcc 6.1 installation requires 8.4 gb. This is not something I can do, because that's huge.
Can someone advise me on the best workaround to install up to date clang on my ~/local?
Please and thanks.
Edit:
Courtesy of Nishant, here is the short answer:
Set up a personal machine running the same linux distro and cross compile using gcc to your specific architecture. For me, I will run a Redhat 6.5 VM and compile using gcc an arm x64 binary. Thanks Nishant!
You can get pre-build binaries for Unix system from LLVM's release website: http://llvm.org/releases/
You can then put the binaries in any local folder you want and source it using the PATH variable, which can be done by modifying your ~/.bashrc file by appending:
export PATH=$PATH:<clang-binary-directory>
Now you will able to use clang from the command line terminal as if it was installed.
If you want to build from source only, you can get older source code of clang which will use gcc 4.4.7 and build it and then use clang to build clang. Or get the latest clang binary and use it to build latest clang.
I'm cross compiling wxWidgets using that tutorial. Could anyone explain me what --host=i586-mingw32msvc does?
I know that prefix give the information where cross-compiler is. However, I compiled minGW from source manually, because then I can use the newest GCC so I can't only copy&paste.
Prefix should be prefix=/usr/local/i386-mingw32 because there is my cross-compiler. And what about host?
I use Lubuntu 14.04 LTS AMD64 .
--host is a typical ./configure option that specifies the "host" system for the program to run on, i.e. the configuration that you will be compiling for.
In other words, --host activates cross-compiling behaviour if you specify a host that is not the same as your build machine.
The format of the host spec differs occasionally between platforms, but it generally takes the form
processorfamily-osfamily[-osversion][-abi]
How can I install gcc on a system that have not any c compiler?
this system is a linux base firewall and have not any c compiler.
I guess you a have an appliance running Linux and shell-access, but neither a package manager nor a compiler is installed.
So, you need to cross-compile gcc and the whole toolchain (at least binutils) - this is quite simple, because the ./configure scripts of gcc, binutils, gdb etc. support cross-compiling with the --target= option. So all you have to do is to find out the target architecure (uname helps) and then download, unpack the gcc sources on a linux-host and run ./configure --target=$YOUR_TARGET.
With this, you now can build a cross-compiler gcc - this still runs on your host, but produces binaries for your target (firewall appliances).
This may already be sufficient for you, a typical desktop PC is much faster than a typical appliance, so it may make sense to compile everything you need on the Desktop PC with the cross-compiler and cross-binutils.
But if you really wish to do so, you can now also use your cross-compiler to compile a gcc running on your target (set this as --host= option) and compiling for your target (set this as --target option).
You can find details about allowed host/targets and examples in the gcc documentation: http://gcc.gnu.org/install/specific.html.
It depends on the distribution, if it's based on debian or some other of the big ones you can install gcc through apt-get or similar tool.
If it's a more basic system you need to compile gcc yourself on another computer and copy it over. It will be easiest if you have another computer with the same architecture (i386, arm or x86_64 for example).
I think that you might want to compile it statically also, so that you don't have dependencies on external libraries.
How do you plan to get all the source code needed for GCC loaded onto your machine? Could you mount the ISO image onto this machine and install from there?
Since you are using Endian Firewall, see "Building a development box" at the following link:
http://alumnus.caltech.edu/~igormt/endian/tips.html
If it's a debian based distribution, you can use
sudo apt-get install gcc
Note: maybe you must change "gcc" by a specific version of the debian package.
Cheers,
I want to avoid problems with compiling my code on amd64, yet I don't have a 64-bit CPU available and have no hopes of getting upgrade to my machine any time soon. I have no dreams of testing the code (although that should theoretically be possible using qemu-system) but I'd like to at least compile the code using gcc -m64.
Basic idea works:
CFLAGS=-m64 CXXFLAGS=-m64 ./configure --host x86_64-debian-linux
However, the code depends on some libraries which I typically install from Debian packages, such as libsdl1.2-dev, libgmp3-dev and such. Obviously, getting 64-bit versions of packages installed alongside of 32-bit versions is not a one-liner.
What would be your practices for installing the 64-bit packages? Where would you put them, how would you get them there and how would you use them?
To repeat, I don't have 64-bit CPU and cannot afford getting a new machine.
I have already set up amd64-libs-dev to give some basic push to gcc's -m64.
Attempted so far:
Setting up a 64-bit chroot jail with debootstrap in order to simplify installation of 64-bit development packages for libraries. Failed since finishing the setup (and installing anything afterwards!) requires 64-bit CPU.
Installing gcc-multilib and g++-multilib. This appears to do nothing beside depending on libc6-dev-amd64 which I already installed through amd64-libs-dev.
If you're using debian, before you can use gcc -m64, you need to install gcc-multilib and g++-multilib. This will also install all files needed to link and create a 64bit binary.
You don't have to have a 64bit capable CPU for this either.
Then you can call GCC as follows:
$ gcc -m64 source.c -o source
As for external libraries, debian takes care of that if you have multilib installed. I have a 32bit machine that compiles 64bit code for another machine and links a handful of libraries (libpng, libz for example). Works great and the executable run (debian to debian).
You want to look into the dchroot package to set up a simple chroot(8) environment -- that way you can compile real amd64 binaries in a real 64-bit setting with proper libraries and dependencies. This surely works the other way (i.e. I am using i386 chroots on amd64 hosts) but I don't see why it shouldn't work the other way if your cpu supports amd64.
Edit: Now that you stress that you do not have a amd64-capable cpu, it gets a little trickier. "In theory" you could just rebuild gcc from source as a cross-compiler. In practice, that may be too much work. Maybe you can just get another headless box for a few dollars and install amd64 on that?
check out this fine article that describes how to easily create a 32bit chroot, where you can install all the 32bit tools (gcc and libs)
Doesn't Debian distinguish between lib32 and lib64 directories? In that case, you can just grab the packages and force them to install, regardless of architecture.
If that does not work (or would hose your system!) I would set up a chroot environment and apt-get the 64-bit libraries into there.
Check out pbuilder, It can create build environments for many architectures, some instructions here
Try cross compiling SDL, gmp and other libraries yourself. Or manually extract the files you need from the Debain packages.