I'm trying to cross compile a Rust project from x86-64 to armv7 (Raspberry Pi 3B+). That project uses the cxx for some of its functionality.
I set up the toolchain, installed the armv7-unknown-linux-gnueabihf target with rustup, and after some trial and error, I copied the required header files to /usr/arm-none-linux-gnueabihf/include. I also copied the /usr/lib/arm-linux-gnueabihf directory from a live Raspbian to /usr/arm-none-linux-gnueabihf/lib.
Then I executed cargo build --target armv7-unknown-linux-gnueabihf. That gives me the following error: https://pastebin.com/2LVZnQMQ.
I then made sure that libc.so.6 is in /usr/arm-none-linux-gnueabihf/lib and libc_nonshared.a is in /usr/arm-linux-gnueabihf/. That did not solve the issue.
I am lost as to what more the linker wants. What else do I need to copy to successfully compare the binary?
Related
I have a prepared a minimal Cmake project containing one cpp file which represent the main and one cpp file which represent the shared library, that prints basically hello world.
https://github.com/courteous/wasmELF.git
The target is to compile this miniaml code with emscripten/clang only and produce
1) one WebAssembly (wasm) binary module version 0x1 (MVP)
2) one ELF 64-bit LSB
without clearing the cmake build directory and rebuilding it again.
Currently i can successfully produce them bought by running the commands
emconfigure cmake ../ -DCMAKE_BUILD_TYPE=WASM
make
and
cmake ../ -DCMAKE_BUILD_TYPE=Linux
make
However the problem is that in order to do that i need to compile the first one with Clang the to remove the build and then to do a second compilation with GCC. I would like Emscripten/Clang to produce them bought instead. I do not want to delete the build directory since the compilation times is taking too long. (Well not in this Project but imagine if the project was much larger)
What i see is that emscripten/clang selects always a target "wasm32-unknown-emscripten"
clang++ -target wasm32-unknown-emscripten
and if i understand that correctly the target should change
I do see that the project is producing LLVM IR bitcode since i have send the flag "flto"
i.e.
file TestSharedClass.cpp.o
TestSharedClass.cpp.o: LLVM IR bitcode
and in the CMakeLists.txt
set(CMAKE_CXX_FLAGS "-flto")
x86_64-unknown-linux-gnu is a supported target by emscripten/Clang
~/Projects/emscripten/emsdk/upstream/bin$ ./llc --version
LLVM (http://llvm.org/):
LLVM version 11.0.0git
Optimized build with assertions.
Default target: x86_64-unknown-linux-gnu
Host CPU: haswell
Registered Targets:
wasm32 - WebAssembly 32-bit
wasm64 - WebAssembly 64-bit
x86 - 32-bit X86: Pentium-Pro and above
x86-64 - 64-bit X86: EM64T and AMD64
In cmake i do have
SET(TARGET x86_64-unknown-linux-gnu)
however when i run
emconfigure cmake ../ -DCMAKE_BUILD_TYPE=Linux
make
i get mainTestFile.js and mainTestFile.wasm instead of ELF 64-bitcode.
what i am doing wrong here. How to tell clang to product once ELF and once wasm from the same code run without having to clear the build directory. This should be possible since clang is producing LLVM IR bitcode. Or do i understand that wrong?
https://github.com/emscripten-core/emscripten/issues/10361
OK that seems to not be possible i.e. the reply from the dev on github states that emcc or emmake can not be used with another target other then wasm32-unknown-emscripten.
I am trying to cross-compile my Rust project on Mac OS to Linux using cargo build --target=x86_64-unknown-linux-musl.
I installed the binary for Linux + musl cross-compilation on mac using brew install FiloSottile/musl-cross/musl-cross as I would ideally want a standalone binary.
I also installed the target using rustup target add x86_64-unknown-linux-gnu
And I have the following in my .cargo/config:
[target.x86_64-unknown-linux-musl]
linker = "x86_64-linux-musl-gcc"
However, I ran into issues with 2 libraries - sqlite3 and pcap:
= note: /usr/local/Cellar/musl-cross/0.9.8/libexec/bin/../lib/gcc/x86_64-linux-musl/6.4.0/../../../../x86_64-linux-musl/bin/ld: cannot find -lsqlite3
/usr/local/Cellar/musl-cross/0.9.8/libexec/bin/../lib/gcc/x86_64-linux-musl/6.4.0/../../../../x86_64-linux-musl/bin/ld: cannot find -lpcap
collect2: error: ld returned 1 exit status
I was able to solve the sqlite3 linker issue by adding features = ["bundled"] to my Cargo.toml file (similar to what is described here - https://users.rust-lang.org/t/linker-cannot-find-lsqlite3/23230/18) as that likely built it from source (which was great) but when I tried doing the same with pcap, it gave the following error:
the package `myProject` depends on `pcap`, with features: `bundled` but `pcap` does not have these features.
After reading somewhere I also tried (with low hopes) of providing the path to the installed libpcap on mac using RUSTPATH='-L/...' cargo build ... but that resulted, of course in undefined symbol errors.
Any ideas how can I get past this issue and cross compile my Rust project into a statically linked binary on macos to run on linux?
Cross compilation does not magically take care of libraries. You cannot just say "I want musl" and have something take care of all your dependencies.
The error message you are seeing is telling you exactly this: it cannot find libsqlite3 and libpcap.
The reason the error for sqlite disappears is because your sqlite library has a bundled feature, which replaces the linking with a built-in sqlite client. This, however, also requests the pcap bundled feature, which does not exist.
You have two options:
If you do not mind the performance loss in the bundled sqlite client, change your feature definition to target the feature of the dependency requiring sqlite
If you want the raw library itself, you will have to compile it for musl
No matter what happens, you will need to cross-compile libpcap for musl with the default sysroot provided by your musl compiler. As this varies per library, you will need to consult the libpcap documentation. once you have done so, you should be able to use the -lpcap flag, and the error will resolve itself.
I am attempting to cross-compile Rust code on my 64-bit x86 laptop to run on the Raspberry Pi Zero W. I installed the arm-unknown-linux-gnueabihf toolchain using Rustup, but when I run cargo build --target arm-unknown-linux-gnueabihf, I get this error:
Internal error occurred: Failed to find tool. Is arm-linux-gnueabihf-gcc installed?
I tried to install the arm-linux-gnueabihf-gcc package from AUR, but that kept failing because of some sort of GPG key error, so I just decided to make my own cross-compiler using crosstool-ng.
I tried to point Cargo at my newly built cross-compiler using a ~/.cargo/config file:
[target.arm-unknown-linux-gnueabihf]
linker = "/home/ibi/x-tools/arm-unknown-linux-gnueabihf/bin/arm-unknown-linux-gnueabihf-gcc"
But Cargo seems to be ignoring this and giving me the same error. How do I fix this?
It worked when I set an environment variable:
$ export CC="/home/ibi/x-tools/arm-unknown-linux-gnueabihf/bin/arm-unknown-linux-gnueabihf-gcc"
Using Android NDK R10E, I am trying to build a shared library for all supported ABI's and I am getting the following error for some but not all ABI's:
[armeabi] SharedLibrary : libMyLib.so /home/user/android-ndk-r10e/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86_64/bin/../lib/gcc/arm-linux-androideabi/4.8/../../../../arm-linux-androideabi/bin/ld:
fatal error: /home/user/source/MyLib/obj/local/armeabi/libMyLib.so: Input/output error
The project successfully builds for arm64-v8a, mips and mips64 but fails with the above error for armeabi, armeabi-v7a, x86 and x86_64.
I have a static library project and another shared library project and they both build successfully for all 7 ABI's.
If I compare the contents of obj/local/ for an ABI that builds and one that does not, they both contain all the same files except for libMyLib.so.
The difference between those two sets of ABIs is that the failing ones link using ld.gold and the working ones use ld.bfd.
Two things to try:
Use the 4.9 toolchain. It hopefully has the bug fix.
If that doesn't work, you can add -fuse-ld=bfd to your ldflags to use bfd even on the architectures that default to gold.
Same issue happened to me in r15c.
The fix was to copy
android-ndk-r15c/toolchains/arm-linux-androideabi-4.9/prebuilt/linux-x86_64/arm-linux-androideabi/bin/ld.bfd over ld.
I had to copy it because I could not easily find a way to specify this flag to CMake to use it while detecting the compiler features.
I am following this site to compile OpenCV for ARM.
It could not find my compiler so i hardcoded it into cmake file
find_program(CMAKE_C_COMPILER NAMES arm-linux-gnueabi-gcc-4.7)
find_program(CMAKE_CXX_COMPILER NAMES arm-linux-gnueabi-g++-4.7)
set(ARM_LINUX_SYSROOT /usr/arm-linux-gnueabi CACHE PATH "ARM cross compilation system root")
It compiles to aproximately 50% and then throws the following error:
Linking CXX shared library ../../lib/libopencv_viz.so
/usr/lib/libvtkCharts.so.5.8.0: file not recognized: File format not recognized
collect2: error: ld returned 1 exit status
I am not every experienced in cross compilation (or straight compilation for the matter). How do i fix this?
I think it is a mismatch between libopencv_viz and libvtkCharts. Some of your 3rdparty libs are built for another platform. These libraries themselves must be recompiled from source to match the details (ABI, dynamic system library dependencies, etc) of the system on which they are intended to be used.
Compiling OpenCV 2.4.10 worked for me. I did not have any preferred version. If you want to compile v3.0 see #Kornel's answer, that suggests to leave viz library out of compilation.
Use this command to checkout v2.4.10
git checkout 2.4.10