Help with musl cmake toolchain file

[Fabian188]

I built a cross compiler on Linux via
TARGET = x86_64-linux-musl
without any issues and installed in to the default local output directory.

I'm currently struggling to use it for my cmake project (with it's external projects).

Does anyone have a cmake toolchain file?

Thanks

[rofl0r]

i don't have a "toolchain file", but a skeleton to use cmake with any cross-compiler:

https://github.com/sabotage-linux/sabotage/blob/master/KEEP/pkg_skel/cmake

just export CROSS_COMPILE to x86_64-linux-musl-, add the directory containing x86_64-linux-musl-gcc to PATH, and export CC/CXX like CC="x86_64-linux-musl-gcc -isystem /path/to/musl-prefix/include -L /path/to/musl-prefix/lib"

[Fabian188]

Thanks for your response. I guess I did most beside setting the path.

It works for other dependencies (muparser and metis) but fails for zlib:

It seems the error is from
/usr/bin/cmake -E cmake_symlink_library libz.so.1.3 libz.so.1 libz.so
I need to dig deeper ...

[ 37%] Building C object CMakeFiles/zlib.dir/zutil.c.o
/home/fwein/code/musl/output/bin/x86_64-linux-musl-gcc --sysroot=/home/fwein/code/musl/output/x86_64-linux-musl -DZLIB_DLL -D_LARGEFILE64_SOURCE=1 -I/home/fwein/code/cfs/release_musl/cfsdeps/zlib/src/zlib-build -I/home/fwein/code/cfs/release_musl/cfsdeps/zlib/src/zlib -m64 -O3  -w -Wno-everything -O3 -DNDEBUG -fPIC -MD -MT CMakeFiles/zlib.dir/zutil.c.o -MF CMakeFiles/zlib.dir/zutil.c.o.d -o CMakeFiles/zlib.dir/zutil.c.o -c /home/fwein/code/cfs/release_musl/cfsdeps/zlib/src/zlib/zutil.c
[ 40%] Linking C shared library libz.so
/usr/bin/cmake -E cmake_link_script CMakeFiles/zlib.dir/link.txt --verbose=1
/home/fwein/code/musl/output/bin/x86_64-linux-musl-gcc --sysroot=/home/fwein/code/musl/output/x86_64-linux-musl -fPIC  -m64 -O3  -w -Wno-everything -O3 -DNDEBUG -Wl,--version-script,"/home/fwein/code/cfs/release_musl/cfsdeps/zlib/src/zlib/zlib.map" -Wl,-rpath-link=/home/fwein/code/musl/output/x86_64-linux-musl/lib -shared -Wl,-soname,libz.so.1 -o libz.so.1.3 CMakeFiles/zlib.dir/adler32.c.o CMakeFiles/zlib.dir/compress.c.o CMakeFiles/zlib.dir/crc32.c.o CMakeFiles/zlib.dir/deflate.c.o CMakeFiles/zlib.dir/gzclose.c.o CMakeFiles/zlib.dir/gzlib.c.o CMakeFiles/zlib.dir/gzread.c.o CMakeFiles/zlib.dir/gzwrite.c.o CMakeFiles/zlib.dir/inflate.c.o CMakeFiles/zlib.dir/infback.c.o CMakeFiles/zlib.dir/inftrees.c.o CMakeFiles/zlib.dir/inffast.c.o CMakeFiles/zlib.dir/trees.c.o CMakeFiles/zlib.dir/uncompr.c.o CMakeFiles/zlib.dir/zutil.c.o 
/usr/bin/cmake -E cmake_symlink_library libz.so.1.3 libz.so.1 libz.so
/usr/bin/cmake: error while loading shared libraries: /usr/lib64/libc.so: invalid ELF header

[Fabian188]

I came a step further: I set LD_LIBRARY_PATH to the musl lib dir, where libc is located and got the error:

`/usr/bin/cmake: /home/fwein/code/musl/output/x86_64-linux-musl/lib/libstdc++.so.6: version GLIBCXX_3.4.30' not found (required by /usr/bin/cmake)``

unsetting LD_LIBRARY_PATH again and building again finished zlib.

That is clearly not a solution but might be a hint. I'm currently stuck in building hdf5 in cross compiler mode.

Probably one shall simply close the issue?