This is my goal: I developed software in Linux and I need to distribute it without source code. The idea is to create a zip file that contains all the necessary items to run the executable. The user will download the zip, extract it, double-click, and the software will start on any Linux-based machine. For motivations that I'm not gonna explain, I can't use deb/rpm/etc or an installer.
The sw has the following dependencies:
some libraries (written by myself that depends on OpenCV), compiled with g++, creating .a files (i.e. static libraries)
OpenCV, in shared libraries, that have several depenencies
I compile my program with gcc, and I link it with:
$ gcc -o my_exe <*.o files> -L<path my_lib> -Wl,--rpath,\$$ORIGIN/lib -lm -lstdc++ -lmy_lib -lopencv
Then I do:
$ ldd my_exe
and I copy all the libraries here listed in ./lib, and I create the .zip.
I copy the zip in an another machine, the dependencies listed by ldd my_exe are satisfied and correctly point to ./lib but when I launch the program, I get the following error:
$ ./my_exe: relocation error: lib/libglib-2.0.so.0: symbol strncmp, version GLIBC_2.2.5 not defined in file libc.so.6 with link time reference
What's wrong? Where is my mistake?
Some additional info:
$ -bash-3.2$ nm -D lib/libc.so.6 |grep strncmp
0000000000083010 T strncmp
$ -bash-3.2$ strings lib/libc.so.6 |grep GLIBC_2.2
GLIBC_2.2.5
GLIBC_2.2.6
I'm using gcc 4.4.5, Ubuntu with a kernel 2.6.35 SMP, 64bit. The machine that I tried is 64bit SMP kernel 2.6 as well.
You seems to re-invent what package managers (for .deb, .rpm, ...) are doing. Why don't you want to make a real package. It would make things simpler and more robust.
And since you code in C++, you will have hard time in making a thing which will work with different versions of libstdc++*.so
Related
I'm very new to Yesod and I'm having trouble building Yesod statically
so I can deploy to Heroku.
I have changed the default .cabal file to reflect static compilation
if flag(production)
cpp-options: -DPRODUCTION
ghc-options: -Wall -threaded -O2 -static -optl-static
else
ghc-options: -Wall -threaded -O0
And it no longer builds. I get a whole bunch of warnings and then a
slew of undefined references like this:
Linking dist/build/personal-website/personal-website ...
/usr/lib/ghc-7.0.3/libHSrts_thr.a(Linker.thr_o): In function
`internal_dlopen':
Linker.c:(.text+0x407): warning: Using 'dlopen' in statically linked
applications requires at runtime the shared libraries from the glibc
version used for linking
/usr/lib/ghc-7.0.3/unix-2.4.2.0/libHSunix-2.4.2.0.a(HsUnix.o): In
function `__hsunix_getpwent':
HsUnix.c:(.text+0xa1): warning: Using 'getpwent' in statically linked
applications requires at runtime the shared libraries from the glibc
version used for linking
/usr/lib/ghc-7.0.3/unix-2.4.2.0/libHSunix-2.4.2.0.a(HsUnix.o): In
function `__hsunix_getpwnam_r':
HsUnix.c:(.text+0xb1): warning: Using 'getpwnam_r' in statically
linked applications requires at runtime the shared libraries from the
glibc version used for linking
/usr/lib/libpq.a(thread.o): In function `pqGetpwuid':
(.text+0x15): warning: Using 'getpwuid_r' in statically linked
applications requires at runtime the shared libraries from the glibc
version used for linking
/usr/lib/libpq.a(ip.o): In function `pg_getaddrinfo_all':
(.text+0x31): warning: Using 'getaddrinfo' in statically linked
applications requires at runtime the shared libraries from the glibc
version used for linking
/usr/lib/ghc-7.0.3/site-local/network-2.3.0.2/
libHSnetwork-2.3.0.2.a(BSD__63.o): In function `sD3z_info':
(.text+0xe4): warning: Using 'gethostbyname' in statically linked
applications requires at runtime the shared libraries from the glibc
version used for linking
/usr/lib/ghc-7.0.3/site-local/network-2.3.0.2/
libHSnetwork-2.3.0.2.a(BSD__164.o): In function `sFKc_info':
(.text+0x12d): warning: Using 'getprotobyname' in statically linked
applications requires at runtime the shared libraries from the glibc
version used for linking
/usr/lib/ghc-7.0.3/site-local/network-2.3.0.2/
libHSnetwork-2.3.0.2.a(BSD__155.o): In function `sFDs_info':
(.text+0x4c): warning: Using 'getservbyname' in statically linked
applications requires at runtime the shared libraries from the glibc
version used for linking
/usr/lib/libpq.a(fe-misc.o): In function `pqSocketCheck':
(.text+0xa2d): undefined reference to `SSL_pending'
/usr/lib/libpq.a(fe-secure.o): In function `SSLerrmessage':
(.text+0x31): undefined reference to `ERR_get_error'
/usr/lib/libpq.a(fe-secure.o): In function `SSLerrmessage':
(.text+0x41): undefined reference to `ERR_reason_error_string'
/usr/lib/libpq.a(fe-secure.o): In function `initialize_SSL':
(.text+0x2f8): undefined reference to `SSL_check_private_key'
/usr/lib/libpq.a(fe-secure.o): In function `initialize_SSL':
(.text+0x3c0): undefined reference to `SSL_CTX_load_verify_locations'
(... snip ...)
If I just compile with just -static and without -optl-static
everything builds fine but the application crashes when it tries to
start on Heroku.
2011-12-28T01:20:51+00:00 heroku[web.1]: Starting process with command
`./dist/build/personal-website/personal-website -p 41083`
2011-12-28T01:20:51+00:00 app[web.1]: ./dist/build/personal-website/
personal-website: error while loading shared libraries: libgmp.so.10:
cannot open shared object file: No such file or directory
2011-12-28T01:20:52+00:00 heroku[web.1]: State changed from starting
to crashed
I tried adding libgmp.so.10 to the LD_LIBRARY_PATH as suggested in here
and then got the following error:
2011-12-28T01:31:23+00:00 app[web.1]: ./dist/build/personal-website/
personal-website: /lib/libc.so.6: version `GLIBC_2.14' not found
(required by ./dist/build/personal-website/personal-website)
2011-12-28T01:31:23+00:00 app[web.1]: ./dist/build/personal-website/
personal-website: /lib/libc.so.6: version `GLIBC_2.14' not found
(required by /app/dist/build/personal-website/libgmp.so.10)
2011-12-28T01:31:25+00:00 heroku[web.1]: State changed from starting
to crashed
2011-12-28T01:31:25+00:00 heroku[web.1]: Process exited
It seems that the version of libc that I'm compiling against is
different. I tried also adding libc to the batch of libraries the
same way I did for libgmp but this results in a segmentation fault
when the application starts on the Heroku side.
Everything works fine on my PC. I'm running 64bit archlinux with ghc
7.0.3. The blog post on the official Yesod blog looked pretty easy
but I'm stumped at this point. Anyone have any ideas? If there's a way to get this thing working without building statically I'm open to that too.
EDIT
Per Employed Russians answer I did the following to fix this.
First created a new directory lib under the project directory and copied the missing shared libraries into it. You can get this information by running ldd path/to/executable and heroku run ldd path/to/executable and comparing the output.
I then did heroku config:add LD_LIBRARY_PATH=./lib so when the application is started the dynamic linker will look for libraries in the new lib directory.
Finally I created an ubuntu 11.10 virtual machine and built and deployed to Heroku from there, this has an old enough glibc that it works on the Heroku host.
Edit:
I've since written a tutorial on the Yesod wiki
I have no idea what Yesod is, but I know exactly what each of your other errors means.
First, you should not try to link statically. The warning you get is exactly right: if you link statically, and use one of the routines for which you are getting the warning, then you must arrange to run on a system with exactly the same version of libc.so.6 as the one you used at build time.
Contrary to popular belief, static linking produces less, not more, portable executables on Linux.
Your other (static) link errors are caused by missing libopenssl.a at link time.
But let's assume that you are going to go the "sane" route, and use dynamic linking.
For dynamic linking, Linux (and most other UNIXes) support backward compatibility: an old binary continues to work on newer systems. But they don't support forward compatibility (a binary built on a newer system will generally not run on an older one).
But that's what you are trying to do: you built on a system with glibc-2.14 (or newer), and you are running on a system with glibc-2.13 (or older).
The other thing you need to know is that glibc is composed of some 200+ binaries that must all match exactly. Two key binaries are /lib/ld-linux.so and /lib/libc.so.6 (but there are many more: libpthread.so.0, libnsl.so.1, etc. etc). If some of these binaries came from different versions of glibc, you usually get a crash. And that is exactly what you got, when you tried to place your glibc-2.14 libc.so.6 on the LD_LIBRARY_PATH -- it no longer matches the system /lib/ld-linux.
So what are the solutions? There are several possibilities (in increasing difficulty):
You could copy ld-2.14.so (the target of /lib/ld-linux symlink) to the target system, and invoke it explicitly:
/path/to/ld-2.14.so --library-path <whatever> /path/to/your/executable
This generally works, but can confuse an application that looks at argv[0], and breaks for applications that re-exec themselves.
You could build on an older system.
You could use appgcc (this option has disappeared, see this for description of what it used to be).
You could set up a chroot environment matching the target system, and build inside that chroot.
You could build yourself a Linux-to-olderLinux crosscompiler
You have several issues.
You should not build production binaries on bleeding edge distributions. The libraries on the production system will not be forward compatible.
You should not link glibc statically - it will always at runtime try to load additional libraries. For example cpu-based assembly. That is what your first warnings are about.
The last linker errors look like they are related to a missing openssl library on the command line.
But all in all - downgrade your distribution.
I had similar problems launching to Heroku (which uses glibc-2.11) where I had an application that required glibc-2.14, but I did not have access to the source and could not re-build it. I tried many things and nothing worked.
My workaround was to launch the service on Amazon Elastic Beanstalk and just provide an API interface.
I found the information provided useful as well, I think the various descriptions miss a critical issue I also ran into while forcing an updated version of Vagrant to start working again.
It's the dependency references internal to something like complicated installs, like Yesod to Heroku. Those interanl refences need to be preserved.
This is the script I wrote to make problems go away (at least, hopefully, for a little while):
#!/bin/bash
cd $HOME/
GLIBC_VERSION="2.17"
GLIBC_PREFIX="/usr/glibc/"
VAGRANT_VERSION="2.2.19"
# Install the basic build system utilities.
yum groupinstall -y "Development tools"
yum install -y curl patchelf
# Grab the tarball with the GNU libc source code.
curl -Lfo glibc-${GLIBC_VERSION}.tar.gz "https://ftp.gnu.org/gnu/glibc/glibc-${GLIBC_VERSION}.tar.gz"
echo "a3b2086d5414e602b4b3d5a8792213feb3be664ffc1efe783a829818d3fca37a glibc-${GLIBC_VERSION}.tar.gz" | sha256sum -c || exit 1
# Extract the secrets and get ready to rumble.
tar xzvf glibc-${GLIBC_VERSION}.tar.gz
# The configure script requrires an independent build directory.
mkdir -p glibc-build && cd glibc-build
# Configure glibc with a GLIBC_PREFIX so it doesn't conflict with distro libc files..
../glibc-${GLIBC_VERSION}/configure --prefix="${GLIBC_PREFIX}" --libdir="${GLIBC_PREFIX}/lib" \
--libexecdir="${GLIBC_PREFIX}/lib" --enable-multi-arch
# Compile and then install GNU libc.
make -j8 && make install
# Download and install Vagrant.
curl -Lfo vagrant_${VAGRANT_VERSION}_x86_64.rpm "https://releases.hashicorp.com/vagrant/${VAGRANT_VERSION}/vagrant_${VAGRANT_VERSION}_x86_64.rpm"
echo "990e8d2159032915f21c0f1ccdcbca1a394f7937e06e43dc1dabe605d208dc20 vagrant_${VAGRANT_VERSION}_x86_64.rpm" | sha256sum -c || exit 1
yum install -y vagrant_${VAGRANT_VERSION}_x86_64.rpm
# Patch the binaries and shared libraries inside the Vagrant directory, so they use the new version of GNU libc.
(find /opt/vagrant/ -type f -exec file {} \; )| grep "dynamically linked" | awk -F':' '{print $1}' | while read FILE ; do
patchelf --set-rpath /opt/vagrant/embedded/lib:/opt/vagrant/embedded/lib64:/usr/glibc/lib:/usr/lib64:/lib64:/lib --set-interpreter /usr/glibc/lib/ld-linux-x86-64.so.2 "${FILE}"
done
The script should be pretty easy to understand, and adapt easily to whatever MacGuffin you want to make work, provied you understand it.
The only tricky part is the rpath you pass to patchelf. Upi need to make sure you preserve the search paths, and precedence your software requires. Or you end up fixing one problem only to create another equally frustrating roadblock.
P.S. Don't forget the update the hashes for any file you down. In particular, you need to compile/install a different version of GNU libc, you will need to update that hash to match the version you want to use.
I have a question and I hope some guru here could help me out :) My goal is simple : (GOAL1) build a older glibc on a newer system and (GOAL2) build old software that can run on older glibc. I am on gcc4.9, glibc2.19, amd64 system. I did compile glibc2.14 and gcc4.7.3 on my system.
(convention : /path/to/libc2.14_dir = $LIBC214, /path/to/gcc4.7.3 = $GCC473)
I am trying to compile bash4.2.53 ( and other softwares coreutil, binutil, qt3.3...) using newly built glibc2.14. My configure and make looks like this : ( I am being in object/build directory )
$ cd /path/to/build/bash-4.2.53
$ CC=$GCC473/bin/gcc CXX=$GCC473/bin/g++ CPP=$GCC473/bin/cpp \
/path/to/source/bash-4.2.53/configure \
--prefix=/path/to/installation/bash-4.2.53
$ make all V=1 \
CFLAGS="-Wl,--rpath=$LIBC214/lib -Wl,--dynamic-linker=$LIBC214/lib/ld-linux-x86-64.so.2" \
CPPFLAGS="-Wl,--rpath=$LIBC214/lib -Wl,--dynamic-linker=$LIBC214/lib/ld-linux-x86-64.so.2" \
CXXFLAGS="-Wl,--rpath=$LIBC214/lib -Wl,--dynamic-linker=$LIBC214/lib/ld-linux-x86-64.so.2"
When make is done in bash4.2.53 build (object) directory, I tried 2 scenarios :
SCENARIO1. Use system's libc2.19
$ ldd ./bash
linux-vdso.so.1 (0x00007ffe677c3000)
libtinfo.so.5 => $MY_PREBUILT_NCURSE/lib/libtinfo.so.5 (0x00007f5d108e3000)
libdl.so.2 => $LIBC214/lib/libdl.so.2 (0x00007f5d106df000)
libc.so.6 => $LIBC214/lib/libc.so.6 (0x00007f5d10354000)
$LIBC214/lib/ld-linux-x86-64.so.2 => /lib64/ld-linux-x86-64.so.2 (0x00007f5d10b0a000)
This line is weird :$LIBC214/lib/ld-linux-x86-64.so.2 => /lib64/ld-linux-x86-64.so.2 (0x00007f5d10b0a000)
$ $LIBC214/bin/ldd ./bash
not a dynamic executable
SCENARIO2. Add $LIBC214/bin to my PATH, $LIBC214/lib to my LD_LIBRARY_PATH
$ ldd ./bash
/bin/bash: $LIBC214/lib/libc.so.6: version `GLIBC_2.15' not found (required by /bin/bash)
$ export SHELL=$PWD/bash
$ ldd --version
/bin/bash: $LIBC214/lib/libc.so.6: version `GLIBC_2.15' not found (required by /bin/bash)
$ ldd ./bash
/bin/bash: $LIBC214/lib/libc.so.6: version `GLIBC_2.15' not found (required by /bin/bash)
As far as I can tell, SCENARIO2 is the right way to run commands. My assumption is that I built glibc2.14 wrongly, that it uses /bin/bash which in turn uses glibc2.19. I am not really sure.
My question:
Could you please explain for me the weird line above and the following line that out put not a dynamic executable?
Could you share me your steps to properly build glibc (GOAL1) and build software using that glibc (GOAL2) ?
What could I do next to solve 2 above scenario?
Thank you.
when you link ELFs, the absolute path to the ldso is hardcoded in it. if you want to use a different one, you can use the -Wl,--dynamic-linker=/path/to/ldso flag to override it. this path is absolute though, so if you try to move your local glibc somewhere else, the ELFs you linked will fail to execute (with errors like no such file). there's no way around this as the system, by design, must have an absolute path in it to the interpreter.
the reason you get weird not a dynamic executable output is that ldd works by actually executing the target ELF and extracting (via debug hooks) the libraries that get loaded. so when you attempt to use a diff ldd like that, glibc gets confused. if you want a stable dependency lister, you might consider something like lddtree from the pax-utils project (most distros have this bundled nowadays). or run readelf -d on the file directly and look at all the DT_NEEDED entries.
trying to build & maintain your own toolchain (glibc, gcc, etc...) is a huge hassle. unless you want to dedicate a lot of time to this, you really should use a project like crosstool-ng to manage it for you. that will allow you to build a full toolchain using an older glibc, and then you can use that to build whatever random packages you like.
if you really really want to spend time doing this all by hand, you should refer to the glibc wiki for building your own glibc and then linking apps against that glibc.
I have Ubuntu 14.04. It came with openssl 1.0.1f. I want to install another openssl version (1.0.2) and I want to compile it by myself.
I configure it as follows:
LDFLAGS='-Wl,--export-dynamic -L/home/myhome/programs/openssl/i/lib
-L/home/myhome/programs/zlib/i/lib'
CPPFLAGS='-I/home/myhome/programs/openssl/i/include
-I/home/myhome/programs/zlib/i/include'
./config --prefix=/home/myhome/programs/openssl/i \
zlib-dynamic shared --with-zlib-lib=/home/myhome/programs/zlib/i/lib \
--with-zlib-include=/home/myhome/programs/zlib/i/include
make
make install
After install, when i check the binary with ldd openssl, and the result is:
...
libssl.so.1.0.0 => /home/myhome/programs/openssl/i/lib/libssl.so.1.0.0 (0x00007f91138c0000)
libcrypto.so.1.0.0 => /home/myhome/programs/openssl/i/lib/libcrypto.so.1.0.0 (0x00007f9113479000)
...
which looks fine. But when I check ldd libssl.so, the result is:
...
libcrypto.so.1.0.0 => /lib/x86_64-linux-gnu/libcrypto.so.1.0.0 (0x00007fac70930000)
...
It still uses the system version of libcrypto. I tried different ways to
build, but result is always stays the same.
My question is how to configure the build in a way, that it can hardcode all binary and library dependencies of shared libraries without using LD_LIBRARY_PATH, or anything like that.
My question is how to configure the build in a way, that it can hardcode all binary and library dependencies of shared libraries without using LD_LIBRARY_PATH, or anything like that.
OpenSSL supports RPATH's out of the box for BSD targets (but not others). From Configure:
# Unlike other OSes (like Solaris, Linux, Tru64, IRIX) BSD run-time
# linkers (tested OpenBSD, NetBSD and FreeBSD) "demand" RPATH set on
# .so objects. Apparently application RPATH is not global and does
# not apply to .so linked with other .so. Problem manifests itself
# when libssl.so fails to load libcrypto.so. One can argue that we
# should engrave this into Makefile.shared rules or into BSD-* config
# lines above. Meanwhile let's try to be cautious and pass -rpath to
# linker only when --prefix is not /usr.
if ($target =~ /^BSD\-/)
{
$shared_ldflag.=" -Wl,-rpath,\$(LIBRPATH)" if ($prefix !~ m|^/usr[/]*$|);
}
The easiest way to do it for OpenSSL 1.0.2 appears to be add it as a CFLAG:
./config -Wl,-rpath=/usr/local/ssl/lib
The next easiest way to do it for OpenSSL 1.0.2 appears to be add a Configure line and hard code the rpath. For example, I am working on Debian x86_64. So I opened the file Configure in an editor, copied linux-x86_64, named it linux-x86_64-rpath, and made the following change to add the -rpath option:
"linux-x86_64-rpath", "gcc:-m64 -DL_ENDIAN -O3 -Wall -Wl,-rpath=/usr/local/ssl/lib::
-D_REENTRANT::-Wl,-rpath=/usr/local/ssl/lib -ldl:SIXTY_FOUR_BIT_LONG RC4_CHUNK DES_INT DES_UNROLL:
${x86_64_asm}:elf:dlfcn:linux-shared:-fPIC:-m64:.so.\$(SHLIB_MAJOR).\$(SHLIB_MINOR):::64",
Above, fields 2 and 6 were changed. They correspond to $cflag and $ldflag in OpenSSL's builds system.
Then, Configure with the new configuration:
$ ./Configure linux-x86_64-rpath shared no-ssl2 no-ssl3 no-comp \
--openssldir=/usr/local/ssl enable-ec_nistp_64_gcc_128
Finally, after make, verify the settings stuck:
$ readelf -d ./libssl.so | grep -i rpath
0x000000000000000f (RPATH) Library rpath: [/usr/local/ssl/lib]
$ readelf -d ./libcrypto.so | grep -i rpath
0x000000000000000f (RPATH) Library rpath: [/usr/local/ssl/lib]
$ readelf -d ./apps/openssl | grep -i rpath
0x000000000000000f (RPATH) Library rpath: [/usr/local/ssl/lib]
Once you perform make install, then ldd will produce expected results:
$ ldd /usr/local/ssl/lib/libssl.so
linux-vdso.so.1 => (0x00007ffceff6c000)
libcrypto.so.1.0.0 => /usr/local/ssl/lib/libcrypto.so.1.0.0 (0x00007ff5eff96000)
...
$ ldd /usr/local/ssl/bin/openssl
linux-vdso.so.1 => (0x00007ffc30d3a000)
libssl.so.1.0.0 => /usr/local/ssl/lib/libssl.so.1.0.0 (0x00007f9e8372e000)
libcrypto.so.1.0.0 => /usr/local/ssl/lib/libcrypto.so.1.0.0 (0x00007f9e832c0000)
...
OpenSSL has a Compilation and Installation on its wiki. This has now been added to the wiki at Compilation and Installation | Using RPATHs
It's 2019, and OpenSSL might have changed a little, so I'll describe how I solved this, on the odd chance someone else might find it useful (and in case I ever need to figure out this command line argument again for myself).
I wanted to build OpenSSL in a way that would cross-compile (using docker containers, because I'm dealing with freakishly old Linux kernels yet modern compilers), yet provide an install that did not depend upon absolute paths, as would be the case using rpath as I've seen described in jww's answer here.
I found I can run OpenSSL's Configure script in this way to achieve what I want (from a bash prompt):
./Configure linux-x86 zlib shared -Wl,-rpath=\\\$\$ORIGIN/../lib
This causes the generated Makefile to build the executables and the shared objects in a way that makes the loader look for dependencies first in "./../lib" (relative to the location of the executable or the shared object), then in the LD_LIBRARY_PATH, etc. That wacky combination of characters properly gets past the bash command line, the script, and the Makefile combinations to create the -rpath argument according to how the linker requires it ($ORIGIN/../lib).
(Obviously, choose the other options that make sense to you.. the key here is in the -Wl,-rpath=\\\$\$ORIGIN/../lib option).
So, if I called ./Configure with a prefix of '--prefix=/opt/spiffness', and later decided to rename 'spiffness' to 'guttersnipe', everything will still work correctly, since the paths are relative rather than absolute.
I have not tried passing the argument into ./config to see if it works there since my use case was a bit special, but I suspect it would. If I were not attempting to cross-compile with dockerized containers, I would prefer using ./config to ./Configure, as it does a decent enough job of examining the current environment to see what kind of binaries to create.
I hope this is useful.
I'm trying to compile "hello world" C application for embedded system with ARM processor running uClinux.
I'm using this toolchain
When I compiled C application with -static compilation flag the application is working fine.
When I removed -static flag - I got an error: can't load library 'libc.so.6'
libc.so.6 does not exists on the target,
into /lib folder on the target device the symbolic link libc.so.0 points to libuClibc-0.9.33.2.so
How can I "tell" compiler to link with libc.so.0?
I had a similar problem when cross-compiling a simple helloworld from an openwrt toolchain (using uClibc, target IPQ4028) to my router Gl-iNet-B1300.
After compiling successfully, I scp the file to the router and when trying to execute this error came up:
root#GL-B1300:~# ./helloworld
/root/helloworld: can't load library 'libc.so.0'
When I run 'ls -la | grep libc.so.' on /lib/, this came up:
libc.so.1 -> libuClibc-1.0.14.so
So as libc.so.0 wasn't there, I just created a link in /lib/
lib/# ln -s libc.so.1 libc.so.0
Running again 'ls -la | grep libc.so.':
libc.so.0 -> libc.so.1
libc.so.1 -> libuClibc-1.0.14.so
And then, executing the file:
root#GL-B1300:~# ./helloworld
Hell! O' world, why won't my code compile?
The value of pi is 3.141593
I guess the real problem here is that the toolchain I'm using is not the right one for the router firmware.
Seems like the toolchain you are using is built for glibc. But the target board has uClibc installed.
These two libraries are incompatible.
At runtime they are incompatible, and at compile-time they are incompatible.
You cannot "tell the compiler to use a different & incompatible library.
You need to obtain a toolchain that is built specifically for uClibc instead of glibc/eglibc.
The site gnuarm.com used to have some reliable toolchains, but that site is no more.
You could try and build your own toolchain using crosstool-NG, which is a lot easier than building the individual toolchain packages. Try the arm-unknown-linux-uclibcgnueabi configuration and customize it to your needs.
You should add the code "load XXX.lib" in your code if you remove -I.
There are some differences between static and dynamic link which you can find in Google.
I'm trying to build a portable version of gcc 4.8.2. (for only C/C++ languages) The end result is have gcc installed into a specific application directory, eg, /opt/gcc-4.8.2 so that I can copy that directory from one computer to another (all computers are either intel corei5 or corei7, running recent Linux versions, eg, Ubuntu 12, Suse 10/11, Centos 5 & 6).
So far I'm able to build gcc ok, using --prefix to have the gcc outputs placed in a single directory (which can then be later copied to the other hosts). I configured & built gcc's dependencies (gmp, mpfr, mpc, isl) to have --disable-shared, so I can be sure that the final gcc, when copied to other hosts, won't complain about missing libraries or symbols.
I have a question with cloog. I configured gcc with --with-cloog (to pick up my locally built cloog, which I built along with the other gcc dependencies). However, what I don't know, is whether I also need to copy the cloog libraries and binary to each host I copy gcc to?
Also, how can I test gcc & cloog interaction? Is there a simple C file example and/or gcc command line that can be used to test whether gcc is successfully making use of cloog?
Additionally, are there any other considerations when trying to build a gcc which I then want to run on other hosts?
It depends if cloog is installed as a shared library libcloog-isl.so.* or as a static one libcloog.a ; use
ldd $(gcc-4.8 -print-file-name=cc1)
to find out. Of course you need to install all the shared libraries dependencies. If libcloog*so appears in the output of above ldd command, it is a shared library. Otherwise a static one.
You could set the LD_LIBRARY_PATH, or add the directory containing libcloog-isl.so.* (e.g. /usr/local/lib/ or /opt/lib/ etc...) to /etc/ld.so.conf (then run ldconfig)
I am not entirely sure your gcc build can run on every platform you mentioned. There might be libc* dependencies. See this. And perhaps also binutils dependencies (notably for gcc-4.8 -flto compilations).
To test gcc just compile with optimizations (e.g. gcc-4.8 -Wall -O3) some non-trivial file.