[llvm-dev] Compiling for baremetal ARMv4 on Ubuntu Linux

[Peter Smith via llvm-dev]

Hello Christian,

I've just retried the runtimes way of building for v6m, v7m and v7e-m
. My cmake command was
ARMEABIGCC=/path/to/gcceabi/arm-none-eabi
cmake \
  -G Ninja\
  -DBAREMETAL_ARMV6M_SYSROOT=${ARMEABIGCC}\
  -DBAREMETAL_ARMV7M_SYSROOT=${ARMEABIGCC}\
  -DBAREMETAL_ARMV7EM_SYSROOT=${ARMEABIGCC}\
  -DCMAKE_BUILD_TYPE=Release\
  -C/path/to/llvm/tools/clang/cmake/caches/BaremetalARM.cmake \
  /path/to/llvm

The cache file requires clang and lld. From the build directory they
will go into lib/clang. That worked for me (TM). Hopefully if you can
edit the paths it will work for you. My guess is that you'll want to
set ARMEABIGCC=/home/crichter/Downloads/gcc-arm-none-eabi-5_4-2016q3/arm-none-eabi

Peter

On Thu, 13 Dec 2018 at 12:08, Christian Richter
<christian.richter at hsu-hh.de> wrote:
>
> Hello Peter and Lists,
>
> thanks a lot, that way it worked out! The final cmake was
>
> cmake -G "Ninja" ../llvm/projects/compiler-rt/ -DCOMPILER_RT_BUILD_BUILTINS=ON -DCOMPILER_RT_BUILD_SANITIZERS=OFF -DCOMPILER_RT_BUILD_XRAY=OFF -DCOMPILER_RT_BUILD_LIBFUZZER=OFF -DCOMPILER_RT_BUILD_PROFILE=OFF -DCMAKE_C_COMPILER=/usr/local/myclang/bin/clang -DCMAKE_AR=/usr/local/myclang/bin/llvm-ar -DCMAKE_NM=/usr/local/myclang/bin/llvm-nm -DCMAKE_RANLIB=/usr/local/myclang/bin/llvm-ranlib -DCMAKE_TRY_COMPILE_TARGET_TYPE=STATIC_LIBRARY -DCMAKE_C_COMPILER_TARGET="arm-linux-gnueabihf" -DCOMPILER_RT_DEFAULT_TARGET_ONLY=ON -DLLVM_CONFIG_PATH=/usr/local/myclang/bin/llvm-config -DCMAKE_ASM_FLAGS="--target=arm-linux-gnueabihf -march=armv7a --gcc-toolchain=/home/crichter/arm-linux-gnueabihf/gcc-arm --sysroot=/home/crichter/arm-linux-gnueabihf/sysroot-glibc/" -DCMAKE_C_FLAGS="--target=arm-linux-gnueabihf -march=armv7a --gcc-toolchain=/home/crichter/arm-linux-gnueabihf/gcc-arm --sysroot=/home/crichter/arm-linux-gnueabihf/sysroot-glibc/"
>
> where sysroot-glibc/  contains sysroot-glibc-8.2-x86_64 and /arm-linux-gnueabihf/gcc-arm contains gcc-arm-8.2 for Aarch32 hard float from https://developer.arm.com/open-source/gnu-toolchain/gnu-a/downloads. This resulted in successfully building libclang_rt.builtins-armhf.a
>
> So next, I tried to use the cmake recipe for BaremetalARM as in the documentation. Therefore, I moved the compiler-rt directory from llvm/projects to llvm/runtimes. I downloaded the latest updates of gcc-arm-none-eabi6/7/8 from https://developer.arm.com/open-source/gnu-toolchain/gnu-rm/downloads and tried to build in a new directory. But whether I gave the -C the path to BaremetalARM.cmake's directory or the file itself, nothing started. I was unsure whether to keep the paths to llvm-ar, llvm-nm and so on as well and whether or not to give the new compiler-rt-directory or the whole llvm-directory as a starting point. Am I using the wrong build directory here? Is this still "Ninja"? The error message (see below) is true: /home/llvm_4rt/llvm/tools/clang/cmake/caches contains no CMakeLists.txt, just the BaremetalARM.cmake among other recipes. Giving -C the file directly just leads to a "this is a file, not a directory" error.
>
> This is (one of my) cmake commands:
>
> root at christian-forschung-virtual-machine:/home/llvm_4rt/buildrecipe# cmake -G "Ninja" ../llvm/runtimes/compiler-rt -DCOMPILER_RT_BUILD_BUILTINS=ON -DCOMPILER_RT_BUILD_SANITIZERS=OFF -DCOMPILER_RT_BUILD_XRAY=OFF -DCOMPILER_RT_BUILD_LIBFUZZER=OFF -DCOMPILER_RT_BUILD_PROFILE=OFF -DCMAKE_C_COMPILER=/usr/local/myclang/bin/clang -DCMAKE_AR=/usr/local/myclang/bin/llvm-ar -DCMAKE_NM=/usr/local/myclang/bin/llvm-nm -DCMAKE_RANLIB=/usr/local/myclang/bin/llvm-ranlib -DCMAKE_TRY_COMPILE_TARGET_TYPE=STATIC_LIBRARY -DCMAKE_C_COMPILER_TARGET="arm-linux-gnueabihf" -DCOMPILER_RT_DEFAULT_TARGET_ONLY=ON -DLLVM_CONFIG_PATH=/usr/local/myclang/bin/llvm-config -DBAREMETAL_ARMV5M_SYSROOT=/home/crichter/Downloads/gcc-arm-none-eabi-5_4-2016q3
> -DBAREMETAL_ARMV6M_SYSROOT=/home/crichter/Downloads/gcc-arm-none-eabi-6-2017-q2-update -DBAREMETAL_ARMV7M_SYSROOT=/home/crichter/Downloads/gcc-arm-none-eabi-7-2018-q2-update -C /home/llvm_4rt/llvm/tools/clang/cmake/caches
>
> loading initial cache file /home/llvm_4rt/llvm/tools/clang/cmake/caches
> CMake Error: Error processing file: /home/llvm_4rt/llvm/tools/clang/cmake/caches
> CMake Error: The source directory "/home/llvm_4rt/llvm/tools/clang/cmake/caches" does not appear to contain CMakeLists.txt.
> Specify --help for usage, or press the help button on the CMake GUI.
>
> So I'm obviously using it wrong, would appreciate any pointers in the right direction!
> Christian
>
>
> On 10.12.2018 17:59, Peter Smith wrote:
>
> Hello Christian,
>
> Yes it does look like clang will add /usr/local/include unless
> --nostdinc is used, although that will mean skipping a lot of other
> include directories that clang will implicitly add based on the
> target. I can think of a couple of ways to proceed:
> 1.) use -nostdinc and add in the directories you need manually
> 2.) use a cross gcc toolchain in a different directory such as one
> from (https://developer.arm.com/open-source/gnu-toolchain/gnu-a/downloads)
> and use --gcc-toolchain and --sysroot.
>
> I must admit I've only ever done 2.) myself as I've wanted to make
> sure I've not inadvertently depended on something on my machine.
>
> Apologies for the confusion.
>
> Peter
>
> On Mon, 10 Dec 2018 at 16:05, Christian Richter
> <christian.richter at hsu-hh.de> wrote:
>
> Hello again!
>
> Tried out the small Hello World Setup, worked as intended:
>
> root at christian-forschung-virtual-machine:/home/progs# clang -v --target=arm-linux-gnueabihf hello.c -o hello -fuse-ld=lld
> clang version 8.0.0 (https://git.llvm.org/git/clang.git/ a152c7a4b7ba8f4cb9532ead9a38a7121db43d50) (https://git.llvm.org/git/llvm.git/ 1959ce6f3e01241919968ac1911fd45660239d23)
> Target: arm-unknown-linux-gnueabihf
> Thread model: posix
> InstalledDir: /usr/local/myclang/bin
> Found candidate GCC installation: /usr/lib/gcc-cross/arm-linux-gnueabihf/7
> Found candidate GCC installation: /usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0
> Selected GCC installation: /usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0
> Candidate multilib: .;@m32
> Selected multilib: .;@m32
>  "/usr/local/myclang/bin/clang-8" -cc1 -triple armv6kz-unknown-linux-gnueabihf -emit-obj -mrelax-all -disable-free -disable-llvm-verifier -discard-value-names -main-file-name hello.c -mrelocation-model static -mthread-model posix -mdisable-fp-elim -fmath-errno -masm-verbose -mconstructor-aliases -fuse-init-array -target-cpu arm1176jzf-s -target-feature +strict-align -target-abi aapcs-linux -mfloat-abi hard -fallow-half-arguments-and-returns -dwarf-column-info -debugger-tuning=gdb -v -resource-dir /usr/local/myclang/lib/clang/8.0.0 -internal-isystem /usr/local/include -internal-isystem /usr/local/myclang/lib/clang/8.0.0/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -fdebug-compilation-dir /home/progs -ferror-limit 19 -fmessage-length 202 -fno-signed-char -fobjc-runtime=gcc -fdiagnostics-show-option -fcolor-diagnostics -o /tmp/hello-98a3a7.o -x c hello.c -faddrsig
> clang -cc1 version 8.0.0 based upon LLVM 8.0.0svn default target x86_64-unknown-linux-gnu
> ignoring nonexistent directory "/include"
> #include "..." search starts here:
> #include <...> search starts here:
>  /usr/local/include
>  /usr/local/myclang/lib/clang/8.0.0/include
>  /usr/include
> End of search list.
>  "/usr/local/myclang/bin/ld.lld" -EL -z relro -X --hash-style=gnu --eh-frame-hdr -m armelf_linux_eabi -dynamic-linker /lib/ld-linux-armhf.so.3 -o hello /usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0/../../../../arm-linux-gnueabihf/lib/../lib/crt1.o /usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0/../../../../arm-linux-gnueabihf/lib/../lib/crti.o /usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0/crtbegin.o -L/usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0 -L/usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0/../../../../arm-linux-gnueabihf/lib/../lib -L/usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0/../../../../lib -L/usr/local/myclang/bin/../lib -L/lib/../lib -L/usr/lib/../lib -L/usr/lib/arm-linux-gnueabihf/../../lib -L/usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0/../../../../arm-linux-gnueabihf/lib -L/usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0/../../.. -L/usr/local/myclang/bin/../lib -L/lib -L/usr/lib /tmp/hello-98a3a7.o -lgcc --as-needed -lgcc_s --no-as-needed -lc -lgcc --as-needed -lgcc_s --no-as-needed /usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0/crtend.o /usr/lib/gcc-cross/arm-linux-gnueabihf/7.3.0/../../../../arm-linux-gnueabihf/lib/../lib/crtn.o
>
> root at christian-forschung-virtual-machine:/home/progs# qemu-arm -L /usr/arm-linux-gnueabihf hello
>
> Hello, World!
>
> So far, so good. The Paths written more readable seem to be
>
> /usr/local/myclang/lib, /lib, /usr/lib, /usr/arm-linux-gnueabihf/lib, so no surprised there.
>
> Then I added the suggested -DCMAKE_ASM_FLAGS to the cmake for the standalone compiler-rt build while leaving out the --sysroot and --gcc-toolchain:
>
> cmake -G "Ninja" ../llvm/projects/compiler-rt/ -DCOMPILER_RT_BUILD_BUILTINS=ON -DCOMPILER_RT_BUILD_SANITIZERS=OFF -DCOMPILER_RT_BUILD_XRAY=OFF -DCOMPILER_RT_BUILD_LIBFUZZER=OFF -DCOMPILER_RT_BUILD_PROFILE=OFF -DCMAKE_C_COMPILER=/usr/local/myclang/bin/clang -DCMAKE_AR=/usr/local/myclang/bin/llvm-ar -DCMAKE_NM=/usr/local/myclang/bin/llvm-nm -DCMAKE_RANLIB=/usr/local/myclang/bin/llvm-ranlib -DCMAKE_TRY_COMPILE_TARGET_TYPE=STATIC_LIBRARY -DCMAKE_C_COMPILER_TARGET="arm-linux-gnueabihf" -DCOMPILER_RT_DEFAULT_TARGET_ONLY=ON -DLLVM_CONFIG_PATH=/usr/local/myclang/bin/llvm-config -DCMAKE_ASM_FLAGS="--target=arm-linux-gnueabihf -march=armv7a" -DCMAKE_C_FLAGS="--target=arm-linux-gnueabihf -march=armv7a"
>
> now "ninja builtins" at least starts working, but fails after a while (see below). The error seems similar to http://lists.llvm.org/pipermail/llvm-dev/2011-September/043289.html to me, so it might still be some variant of the problem from before: Using a x86-header where an ARM one would be needed.
>
> The ninja builtins output:
>
> root at christian-forschung-virtual-machine:/home/llvm_all/buildrtonly# ninja builtins
> [147/207] Building C object lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/emutls.c.o
> FAILED: lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/emutls.c.o
> /usr/local/myclang/bin/clang --target=arm-linux-gnueabihf -DVISIBILITY_HIDDEN  --target=arm-linux-gnueabihf -march=armv7a -Wall -Wno-unused-parameter    -fno-lto -std=c11 -fPIC -fno-builtin -fvisibility=hidden -fomit-frame-pointer -fomit-frame-pointer -DCOMPILER_RT_ARMHF_TARGET -MD -MT lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/emutls.c.o -MF lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/emutls.c.o.d -o lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/emutls.c.o   -c /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/emutls.c
> In file included from /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/emutls.c:41:
> /usr/include/pthread.h:682:6: error: 'regparm' is not valid on this platform
>      __cleanup_fct_attribute;
>      ^~~~~~~~~~~~~~~~~~~~~~~
> /usr/include/bits/pthreadtypes-arch.h:103:50: note: expanded from macro '__cleanup_fct_attribute'
> # define __cleanup_fct_attribute __attribute__ ((__regparm__ (1)))
>                                                  ^            ~
> In file included from /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/emutls.c:41:
> /usr/include/pthread.h:694:3: error: 'regparm' is not valid on this platform
>   __cleanup_fct_attribute;
>   ^~~~~~~~~~~~~~~~~~~~~~~
> /usr/include/bits/pthreadtypes-arch.h:103:50: note: expanded from macro '__cleanup_fct_attribute'
> # define __cleanup_fct_attribute __attribute__ ((__regparm__ (1)))
>                                                  ^            ~
> In file included from /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/emutls.c:41:
> /usr/include/pthread.h:735:6: error: 'regparm' is not valid on this platform
>      __cleanup_fct_attribute __attribute__ ((__noreturn__))
>      ^~~~~~~~~~~~~~~~~~~~~~~
> /usr/include/bits/pthreadtypes-arch.h:103:50: note: expanded from macro '__cleanup_fct_attribute'
> # define __cleanup_fct_attribute __attribute__ ((__regparm__ (1)))
>                                                  ^            ~
> 3 errors generated.
> [148/207] Building C object lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/gcc_personality_v0.c.o
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:148:47: warning: declaration of 'struct _Unwind_Exception' will not be visible outside of this function [-Wvisibility]
> _Unwind_Reason_Code __gnu_unwind_frame(struct _Unwind_Exception *,
>                                               ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:153:23: warning: declaration of 'struct _Unwind_Exception' will not be visible outside of this function [-Wvisibility]
> continueUnwind(struct _Unwind_Exception *exceptionObject,
>                       ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:160:28: warning: incompatible pointer types passing 'struct _Unwind_Exception *' to parameter of type 'struct _Unwind_Exception *' [-Wincompatible-pointer-types]
>     if (__gnu_unwind_frame(exceptionObject, context) != _URC_OK)
>                            ^~~~~~~~~~~~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:148:66: note: passing argument to parameter here
> _Unwind_Reason_Code __gnu_unwind_frame(struct _Unwind_Exception *,
>                                                                  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:184:38: warning: declaration of 'struct _Unwind_Exception' will not be visible outside of this function [-Wvisibility]
>          _Unwind_State state, struct _Unwind_Exception *exceptionObject,
>                                      ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:202:31: warning: incompatible pointer types passing 'struct _Unwind_Exception *' to parameter of type 'struct _Unwind_Exception *' [-Wincompatible-pointer-types]
>         return continueUnwind(exceptionObject, context);
>                               ^~~~~~~~~~~~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:153:42: note: passing argument to parameter 'exceptionObject' here
> continueUnwind(struct _Unwind_Exception *exceptionObject,
>                                          ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:207:31: warning: incompatible pointer types passing 'struct _Unwind_Exception *' to parameter of type 'struct _Unwind_Exception *' [-Wincompatible-pointer-types]
>         return continueUnwind(exceptionObject, context);
>                               ^~~~~~~~~~~~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:153:42: note: passing argument to parameter 'exceptionObject' here
> continueUnwind(struct _Unwind_Exception *exceptionObject,
>                                          ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:250:27: warning: incompatible pointer types passing 'struct _Unwind_Exception *' to parameter of type 'struct _Unwind_Exception *' [-Wincompatible-pointer-types]
>     return continueUnwind(exceptionObject, context);
>                           ^~~~~~~~~~~~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/gcc_personality_v0.c:153:42: note: passing argument to parameter 'exceptionObject' here
> continueUnwind(struct _Unwind_Exception *exceptionObject,
>                                          ^
> 7 warnings generated.
> [152/207] Building ASM object lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/aeabi_cdcmp.S.o
> ninja: build stopped: subcommand failed.
>
> Almost there! Thanks in advance!
>
> Christian
>
>
>
> On 07.12.2018 17:40, Peter Smith wrote:
>
> Hello Christian,
>
> I've put some comments inline
>
> On Fri, 7 Dec 2018 at 15:48, Christian Richter via llvm-dev
> <llvm-dev at lists.llvm.org> wrote:
>
> Hello,
>
> on the problems cross-building compiler-rt: Tried to follow https://llvm.org/docs/HowToCrossCompileBuiltinsOnArm.html which lead to this cmake:
>
> cmake -G "Ninja" ../llvm/projects/compiler-rt/ -DCOMPILER_RT_BUILD_BUILTINS=ON -DCOMPILER_RT_BUILD_SANITIZERS=OFF -DCOMPILER_RT_BUILD_XRAY=OFF -DCOMPILER_RT_BUILD_LIBFUZZER=OFF -DCOMPILER_RT_BUILD_PROFILE=OFF -DCMAKE_C_COMPILER=/usr/local/myclang/bin/clang -DCMAKE_AR=/usr/local/myclang/bin/llvm-ar -DCMAKE_NM=/usr/local/myclang/bin/llvm-nm -DCMAKE_RANLIB=/usr/local/myclang/bin/llvm-ranlib -DCMAKE_TRY_COMPILE_TARGET_TYPE=STATIC_LIBRARY  -DCMAKE_C_COMPILER_TARGET="arm-linux-gnueabihf" -DCOMPILER_RT_DEFAULT_TARGET_ONLY=ON -DLLVM_CONFIG_PATH=/usr/local/myclang/bin/llvm-config -DCMAKE_C_FLAGS="--target=arm-linux-gnueabihf -march=armv7a --gcc-toolchain=/usr/arm-linux-gnueabihf --sysroot=/usr/arm-linux-gnueabihf/lib"
>
> Some small notes:
>
> - Used -DCMAKE_TRY_COMPILE_TARGET_TYPE=STATIC_LIBRARY instead of  -DCMAKE_EXE_LINKER_FLAGS="-fuse-ld=lld" as Peter Smith suggested because it actually is a library and therefore does not need to be linked. If I do not change that, the cmake does not work (see below).
>
> - used -G "Ninja" although not explicitly stated in the tutorial as they use "ninja builtins" next.
>
> - had to change --march=armv7a to -march=armv7a as clang did not accept the first one.
>
> the cmake was successful, but the ninja builtins was not (see both outputs below). Am I doing the --gcc-toolchain / --sysroot part right? These are just the places where the result of "apt install arm-linux-gnueabihf" lives.
>
> cmake output with -DCMAKE_EXE_LINKER_FLAGS="-fuse-ld=lld":
>
> Thanks for the comments. I will try and revisit that document next
> week and will post an update.
>
> root at christian-forschung-virtual-machine:/home/llvm_all/buildrtonly# cmake -G "Ninja" ../llvm/projects/compiler-rt/ -DCOMPILER_RT_BUILD_BUILTINS=ON -DCOMPILER_RT_BUILD_SANITIZERS=OFF -DCOMPILER_RT_BUILD_XRAY=OFF -DCOMPILER_RT_BUILD_LIBFUZZER=OFF -DCOMPILER_RT_BUILD_PROFILE=OFF -DCMAKE_C_COMPILER=/usr/local/myclang/bin/clang -DCMAKE_AR=/usr/local/myclang/bin/llvm-ar -DCMAKE_NM=/usr/local/myclang/bin/llvm-nm -DCMAKE_RANLIB=/usr/local/myclang/bin/llvm-ranlib -DCMAKE_EXE_LINKER_FLAGS="-fuse-ld=lld" -DCMAKE_C_COMPILER_TARGET="arm-linux-gnueabihf" -DCOMPILER_RT_DEFAULT_TARGET_ONLY=ON -DLLVM_CONFIG_PATH=/usr/local/myclang/bin/llvm-config -DCMAKE_C_FLAGS="--target=arm-linux-gnueabihf -march=armv7a --gcc-toolchain=/usr/arm-linux-gnueabihf --sysroot=/usr/arm-linux-gnueabihf/lib"
> -- The C compiler identification is Clang 8.0.0
> -- The CXX compiler identification is Clang 8.0.0
> -- The ASM compiler identification is unknown
> -- Found assembler: /usr/local/myclang/bin/clang
> -- Check for working C compiler: /usr/local/myclang/bin/clang
> -- Check for working C compiler: /usr/local/myclang/bin/clang -- broken
> CMake Error at /usr/share/cmake-3.10/Modules/CMakeTestCCompiler.cmake:52 (message):
>   The C compiler
>
>     "/usr/local/myclang/bin/clang"
>
>   is not able to compile a simple test program.
>
>   It fails with the following output:
>
>     Change Dir: /home/llvm_all/buildrtonly/CMakeFiles/CMakeTmp
>
>     Run Build Command:"/usr/bin/ninja" "cmTC_22d97"
>     [1/2] Building C object CMakeFiles/cmTC_22d97.dir/testCCompiler.c.o
>     [2/2] Linking C executable cmTC_22d97
>     FAILED: cmTC_22d97
>     : && /usr/local/myclang/bin/clang --target=arm-linux-gnueabihf --target=arm-linux-gnueabihf -march=armv7a --gcc-toolchain=/usr/arm-linux-gnueabihf --sysroot=/usr/arm-linux-gnueabihf/lib  -fuse-ld=lld CMakeFiles/cmTC_22d97.dir/testCCompiler.c.o  -o cmTC_22d97   && :
>     ld.lld: error: cannot open crt1.o: No such file or directory
>     ld.lld: error: cannot open crti.o: No such file or directory
>     ld.lld: error: cannot open crtbegin.o: No such file or directory
>     ld.lld: error: unable to find library -lgcc
>     ld.lld: error: unable to find library -lgcc_s
>     ld.lld: error: unable to find library -lc
>     ld.lld: error: unable to find library -lgcc
>     ld.lld: error: unable to find library -lgcc_s
>     ld.lld: error: cannot open crtend.o: No such file or directory
>     ld.lld: error: cannot open crtn.o: No such file or directory
>     clang-8: error: linker command failed with exit code 1 (use -v to see invocation)
>     ninja: build stopped: subcommand failed.
>
> CMake will not be able to correctly generate this project.
> Call Stack (most recent call first):
>   CMakeLists.txt:10 (project)
> -- Configuring incomplete, errors occurred!
> See also "/home/llvm_all/buildrtonly/CMakeFiles/CMakeOutput.log".
> See also "/home/llvm_all/buildrtonly/CMakeFiles/CMakeError.log".
>
>
> Note: Googling this error suggested installing gcc-multilib or linking "sudo ln -s /usr/lib/x86_64-linux-gnu /usr/lib64" (which both did not fix it). But the crt1.o that lld does not seem to find is probably the one from arm-linux-gnueabihf, right? "Locate" says it's right in /usr/arm-linux-gnueabihf/lib.
>
> The instructions to use --gcc-toolchain and --sysroot work well for a
> separate toolchain install directory. They don't seem to work as well
> for a debian multiarch style installation. I think it will be worth
> trying to compile helloworld outside of cmake. If you can get that to
> work then this might help guide us to what flags to use.
>
> On my ubuntu 16.04 machine I've got /usr/arm-linux-gnueabihf and
> /usr/include/arm-linux-gnueabihf and /usr/lib/arm-linux-gnueabihf
> With this configuration the clang linux driver is able to find the
> libraries without the sysroot and gcc-toolchain as it is effectively
> root. Can you try with a simple helloworld program:
> clang --target=arm-linux-gnueabihf hello.c -o hello -fuse-ld=lld
> qemu-arm -L /usr/arm-linux-gnueabihf hello
> If all is well you should see qemu-arm print Hello World. You may need
> to install the package qemu-user if you've not already done so.
>
> With the -v option clang will tell you where it is searching for
> headers and libraries, I've often found that useful in trying to find
> out what is going.
>
> Assuming that this has worked for you can you try removing
> "--gcc-toolchain=/usr/arm-linux-gnueabihf
> --sysroot=/usr/arm-linux-gnueabihf/lib" from your flags in the cmake
> build.
>
> For the errors below it looks like clang is using the default target
> for assembler, note that --target=arm-linux-gnueabihf is missing. I
> have seen that before, and the solution I found was to pass
> -DCMAKE_ASM_FLAGS="same as C flags including
> --target=arm-linux-gnueabihf and -march=armv7a"
>
> Thanks for reporting the problems. If I get time next week I'll have a
> go at improving the documentation.
>
> Peter
>
> Thanks so far!
>
> Christian
>
>
> cmake output with STATIC_LIBRARY:
>
> -- The C compiler identification is Clang 8.0.0
> -- The CXX compiler identification is Clang 8.0.0
> -- The ASM compiler identification is Clang
> -- Found assembler: /usr/local/myclang/bin/clang
> -- Check for working C compiler: /usr/local/myclang/bin/clang
> -- Check for working C compiler: /usr/local/myclang/bin/clang -- works
> -- Detecting C compiler ABI info
> -- Detecting C compiler ABI info - done
> -- Detecting C compile features
> -- Detecting C compile features - done
> -- Check for working CXX compiler: /usr/local/myclang/bin/clang++
> -- Check for working CXX compiler: /usr/local/myclang/bin/clang++ -- works
> -- Detecting CXX compiler ABI info
> -- Detecting CXX compiler ABI info - done
> -- Detecting CXX compile features
> -- Detecting CXX compile features - done
> -- Looking for unwind.h
> -- Looking for unwind.h - found
> -- Found PythonInterp: /usr/bin/python2.7 (found version "2.7.15")
> -- Looking for fopen in c
> -- Looking for fopen in c - found
> -- Looking for __gcc_personality_v0 in gcc_s
> -- Looking for __gcc_personality_v0 in gcc_s - found
> -- Performing Test COMPILER_RT_HAS_NODEFAULTLIBS_FLAG
> -- Performing Test COMPILER_RT_HAS_NODEFAULTLIBS_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FFREESTANDING_FLAG
> -- Performing Test COMPILER_RT_HAS_FFREESTANDING_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FPIC_FLAG
> -- Performing Test COMPILER_RT_HAS_FPIC_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FPIE_FLAG
> -- Performing Test COMPILER_RT_HAS_FPIE_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FNO_BUILTIN_FLAG
> -- Performing Test COMPILER_RT_HAS_FNO_BUILTIN_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FNO_EXCEPTIONS_FLAG
> -- Performing Test COMPILER_RT_HAS_FNO_EXCEPTIONS_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FOMIT_FRAME_POINTER_FLAG
> -- Performing Test COMPILER_RT_HAS_FOMIT_FRAME_POINTER_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FUNWIND_TABLES_FLAG
> -- Performing Test COMPILER_RT_HAS_FUNWIND_TABLES_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FNO_STACK_PROTECTOR_FLAG
> -- Performing Test COMPILER_RT_HAS_FNO_STACK_PROTECTOR_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FNO_SANITIZE_SAFE_STACK_FLAG
> -- Performing Test COMPILER_RT_HAS_FNO_SANITIZE_SAFE_STACK_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FVISIBILITY_HIDDEN_FLAG
> -- Performing Test COMPILER_RT_HAS_FVISIBILITY_HIDDEN_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FRTTI_FLAG
> -- Performing Test COMPILER_RT_HAS_FRTTI_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FNO_RTTI_FLAG
> -- Performing Test COMPILER_RT_HAS_FNO_RTTI_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FNO_FUNCTION_SECTIONS_FLAG
> -- Performing Test COMPILER_RT_HAS_FNO_FUNCTION_SECTIONS_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_STD_CXX11_FLAG
> -- Performing Test COMPILER_RT_HAS_STD_CXX11_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FTLS_MODEL_INITIAL_EXEC
> -- Performing Test COMPILER_RT_HAS_FTLS_MODEL_INITIAL_EXEC - Success
> -- Performing Test COMPILER_RT_HAS_FNO_LTO_FLAG
> -- Performing Test COMPILER_RT_HAS_FNO_LTO_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_MSSE3_FLAG
> -- Performing Test COMPILER_RT_HAS_MSSE3_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_MSSE4_2_FLAG
> -- Performing Test COMPILER_RT_HAS_MSSE4_2_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_SYSROOT_FLAG
> -- Performing Test COMPILER_RT_HAS_SYSROOT_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_MCRC_FLAG
> -- Performing Test COMPILER_RT_HAS_MCRC_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_FVISIBILITY_INLINES_HIDDEN_FLAG
> -- Performing Test COMPILER_RT_HAS_FVISIBILITY_INLINES_HIDDEN_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_GR_FLAG
> -- Performing Test COMPILER_RT_HAS_GR_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_GS_FLAG
> -- Performing Test COMPILER_RT_HAS_GS_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_MT_FLAG
> -- Performing Test COMPILER_RT_HAS_MT_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_Oy_FLAG
> -- Performing Test COMPILER_RT_HAS_Oy_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_GLINE_TABLES_ONLY_FLAG
> -- Performing Test COMPILER_RT_HAS_GLINE_TABLES_ONLY_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_G_FLAG
> -- Performing Test COMPILER_RT_HAS_G_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_Zi_FLAG
> -- Performing Test COMPILER_RT_HAS_Zi_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_WALL_FLAG
> -- Performing Test COMPILER_RT_HAS_WALL_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_WERROR_FLAG
> -- Performing Test COMPILER_RT_HAS_WERROR_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_WFRAME_LARGER_THAN_FLAG
> -- Performing Test COMPILER_RT_HAS_WFRAME_LARGER_THAN_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_WGLOBAL_CONSTRUCTORS_FLAG
> -- Performing Test COMPILER_RT_HAS_WGLOBAL_CONSTRUCTORS_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_WC99_EXTENSIONS_FLAG
> -- Performing Test COMPILER_RT_HAS_WC99_EXTENSIONS_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_WGNU_FLAG
> -- Performing Test COMPILER_RT_HAS_WGNU_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_WNON_VIRTUAL_DTOR_FLAG
> -- Performing Test COMPILER_RT_HAS_WNON_VIRTUAL_DTOR_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_WVARIADIC_MACROS_FLAG
> -- Performing Test COMPILER_RT_HAS_WVARIADIC_MACROS_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_WUNUSED_PARAMETER_FLAG
> -- Performing Test COMPILER_RT_HAS_WUNUSED_PARAMETER_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_WCOVERED_SWITCH_DEFAULT_FLAG
> -- Performing Test COMPILER_RT_HAS_WCOVERED_SWITCH_DEFAULT_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_W4_FLAG
> -- Performing Test COMPILER_RT_HAS_W4_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_WX_FLAG
> -- Performing Test COMPILER_RT_HAS_WX_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_WD4146_FLAG
> -- Performing Test COMPILER_RT_HAS_WD4146_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_WD4291_FLAG
> -- Performing Test COMPILER_RT_HAS_WD4291_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_WD4221_FLAG
> -- Performing Test COMPILER_RT_HAS_WD4221_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_WD4391_FLAG
> -- Performing Test COMPILER_RT_HAS_WD4391_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_WD4722_FLAG
> -- Performing Test COMPILER_RT_HAS_WD4722_FLAG - Failed
> -- Performing Test COMPILER_RT_HAS_WD4800_FLAG
> -- Performing Test COMPILER_RT_HAS_WD4800_FLAG - Failed
> -- Looking for __func__
> -- Looking for __func__ - found
> -- Looking for dlopen in dl
> -- Looking for dlopen in dl - found
> -- Looking for shm_open in rt
> -- Looking for shm_open in rt - found
> -- Looking for pow in m
> -- Looking for pow in m - found
> -- Looking for pthread_create in pthread
> -- Looking for pthread_create in pthread - found
> -- Looking for setupterm in terminfo
> -- Looking for setupterm in terminfo - found
> -- Looking for __cxa_throw in c++
> -- Looking for __cxa_throw in c++ - found
> -- Looking for __cxa_throw in stdc++
> -- Looking for __cxa_throw in stdc++ - found
> -- Compiler-RT supported architectures: armhf
> -- Performing Test COMPILER_RT_HAS_STD_C11_FLAG
> -- Performing Test COMPILER_RT_HAS_STD_C11_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_VISIBILITY_HIDDEN_FLAG
> -- Performing Test COMPILER_RT_HAS_VISIBILITY_HIDDEN_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_OMIT_FRAME_POINTER_FLAG
> -- Performing Test COMPILER_RT_HAS_OMIT_FRAME_POINTER_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_FREESTANDING_FLAG
> -- Performing Test COMPILER_RT_HAS_FREESTANDING_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_XRAY_COMPILER_FLAG
> -- Performing Test COMPILER_RT_HAS_XRAY_COMPILER_FLAG - Success
> -- Performing Test COMPILER_RT_HAS_ATOMIC_KEYWORD
> -- Performing Test COMPILER_RT_HAS_ATOMIC_KEYWORD - Success
> -- Builtin supported architectures: armhf
> -- Looking for __VFP_FP__
> -- Looking for __VFP_FP__ - found
> -- Configuring done
> -- Generating done
> -- Build files have been written to: /home/llvm_all/buildrtonly
>
> --------------------------------------
>
> ninja output:
>
>
> root at christian-forschung-virtual-machine:/home/llvm_all/buildrtonly# ninja builtins
>
> [1/207] Building ASM object lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/bswapsi2.S.o
> FAILED: lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/bswapsi2.S.o
> /usr/local/myclang/bin/clang -DVISIBILITY_HIDDEN  -fno-lto -std=c11 -fPIC -fno-builtin -fvisibility=hidden -fomit-frame-pointer -fomit-frame-pointer -DCOMPILER_RT_ARMHF_TARGET -MD -MT lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/bswapsi2.S.o -MF lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/bswapsi2.S.o.d -o lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/bswapsi2.S.o -c /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapsi2.S
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapsi2.S:12:2: error: unknown directive
>  .syntax unified
>  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapsi2.S:25:3: error: invalid instruction mnemonic 'eor'
>   eor r1, r0, r0, ror #16
>   ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapsi2.S:26:15: error: unknown token in expression
>   bic r1, r1, #0xff0000
>               ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapsi2.S:27:3: error: unknown use of instruction mnemonic without a size suffix
>   mov r1, r1, lsr #8
>   ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapsi2.S:28:3: error: invalid instruction mnemonic 'eor'
>   eor r0, r1, r0, ror #8
>   ^~~
> [2/207] Building ASM object lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/bswapdi2.S.o
> FAILED: lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/bswapdi2.S.o
> /usr/local/myclang/bin/clang -DVISIBILITY_HIDDEN  -fno-lto -std=c11 -fPIC -fno-builtin -fvisibility=hidden -fomit-frame-pointer -fomit-frame-pointer -DCOMPILER_RT_ARMHF_TARGET -MD -MT lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/bswapdi2.S.o -MF lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/bswapdi2.S.o.d -o lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/bswapdi2.S.o -c /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S:12:2: error: unknown directive
>  .syntax unified
>  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S:26:5: error: invalid instruction mnemonic 'eor'
>     eor r2, r0, r0, ror #16
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S:27:17: error: unknown token in expression
>     bic r2, r2, #0xff0000
>                 ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S:28:5: error: unknown use of instruction mnemonic without a size suffix
>     mov r2, r2, lsr #8
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S:29:5: error: invalid instruction mnemonic 'eor'
>     eor r2, r2, r0, ror #8
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S:31:5: error: invalid instruction mnemonic 'eor'
>     eor r0, r1, r1, ror #16
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S:32:17: error: unknown token in expression
>     bic r0, r0, #0xff0000
>                 ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S:33:5: error: unknown use of instruction mnemonic without a size suffix
>     mov r0, r0, lsr #8
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S:34:5: error: invalid instruction mnemonic 'eor'
>     eor r0, r0, r1, ror #8
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/bswapdi2.S:39:5: error: unknown use of instruction mnemonic without a size suffix
>     mov r1, r2
>     ^
> [3/207] Building ASM object lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/comparesf2.S.o
> FAILED: lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/comparesf2.S.o
> /usr/local/myclang/bin/clang -DVISIBILITY_HIDDEN  -fno-lto -std=c11 -fPIC -fno-builtin -fvisibility=hidden -fomit-frame-pointer -fomit-frame-pointer -DCOMPILER_RT_ARMHF_TARGET -MD -MT lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/comparesf2.S.o -MF lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/comparesf2.S.o.d -o lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/comparesf2.S.o -c /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:41:2: error: unknown directive
>  .syntax unified
>  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:45:1: error: unexpected token at start of statement
> @ int __eqsf2(float a, float b)
> ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:50:5: error: invalid operand for instruction
>     vmov r0, s0
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:51:5: error: invalid operand for instruction
>     vmov r1, s1
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:53:5: error: unknown use of instruction mnemonic without a size suffix
>     mov r2, r0, lsl #1
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:54:5: error: unknown use of instruction mnemonic without a size suffix
>     mov r3, r1, lsl #1
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:56:5: error: invalid instruction mnemonic 'orrs'
>     orrs r12, r2, r3, lsr #1
>     ^~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:58:5: error: invalid instruction mnemonic 'it'
>     it ne
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:59:5: error: invalid instruction mnemonic 'eorsne'
>     eorsne r12, r0, r1
>     ^~~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:61:5: error: invalid instruction mnemonic 'it'
>     it pl
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:62:5: error: invalid instruction mnemonic 'subspl'
>     subspl r0, r2, r3
>     ^~~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:64:5: error: invalid instruction mnemonic 'it'
>     it lo
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:65:5: error: invalid instruction mnemonic 'mvnlo'
>     mvnlo r0, r1, asr #31
>     ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:67:5: error: invalid instruction mnemonic 'it'
>     it hi
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:68:5: error: invalid instruction mnemonic 'movhi'
>     movhi r0, r1, asr #31
>     ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:70:5: error: invalid instruction mnemonic 'it'
>     it ne
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:71:19: error: unknown token in expression
>     orrne r0, r0, #1
>                   ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:167:13: error: unknown token in expression
>     cmp r2, #0xff000000
>             ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:168:5: error: invalid instruction mnemonic 'ite'
>     ite ls
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:169:15: error: unknown token in expression
>     cmpls r3, #0xff000000
>               ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:170:15: error: unknown token in expression
>     movhi r0, #1
>               ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:179:1: error: unexpected token at start of statement
> @ int __gtsf2(float a, float b)
> ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:188:5: error: invalid operand for instruction
>     vmov r0, s0
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:189:5: error: invalid operand for instruction
>     vmov r1, s1
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:191:5: error: unknown use of instruction mnemonic without a size suffix
>     mov r2, r0, lsl #1
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:192:5: error: unknown use of instruction mnemonic without a size suffix
>     mov r3, r1, lsl #1
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:193:5: error: invalid instruction mnemonic 'orrs'
>     orrs r12, r2, r3, lsr #1
>     ^~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:194:5: error: invalid instruction mnemonic 'it'
>     it ne
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:195:5: error: invalid instruction mnemonic 'eorsne'
>     eorsne r12, r0, r1
>     ^~~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:196:5: error: invalid instruction mnemonic 'it'
>     it pl
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:197:5: error: invalid instruction mnemonic 'subspl'
>     subspl r0, r2, r3
>     ^~~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:198:5: error: invalid instruction mnemonic 'it'
>     it lo
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:199:5: error: invalid instruction mnemonic 'mvnlo'
>     mvnlo r0, r1, asr #31
>     ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:200:5: error: invalid instruction mnemonic 'it'
>     it hi
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:201:5: error: invalid instruction mnemonic 'movhi'
>     movhi r0, r1, asr #31
>     ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:202:5: error: invalid instruction mnemonic 'it'
>     it ne
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:203:19: error: unknown token in expression
>     orrne r0, r0, #1
>                   ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:204:13: error: unknown token in expression
>     cmp r2, #0xff000000
>             ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:205:5: error: invalid instruction mnemonic 'ite'
>     ite ls
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:206:15: error: unknown token in expression
>     cmpls r3, #0xff000000
>               ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:207:15: error: unknown token in expression
>     movhi r0, #-1
>               ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:214:1: error: unexpected token at start of statement
> @ int __unordsf2(float a, float b)
> ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:220:5: error: invalid operand for instruction
>     vmov r0, s0
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:221:5: error: invalid operand for instruction
>     vmov r1, s1
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:224:18: error: unknown token in expression
>     lsls r2, r0, #1
>                  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:225:18: error: unknown token in expression
>     lsls r3, r1, #1
>                  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:226:14: error: unknown token in expression
>     movs r0, #0
>              ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:277:13: error: unknown token in expression
>     cmp r2, #0xff000000
>             ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:278:5: error: invalid instruction mnemonic 'ite'
>     ite ls
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:279:15: error: unknown token in expression
>     cmpls r3, #0xff000000
>               ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:280:15: error: unknown token in expression
>     movhi r0, #1
>               ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:287:2: error: invalid operand for instruction
>  vmov s0, r0
>  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:288:2: error: invalid operand for instruction
>  vmov s1, r1
>  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/comparesf2.S:289:2: error: invalid instruction mnemonic 'b'
>  b __unordsf2
>  ^
> [4/207] Building ASM object lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/clzsi2.S.o
> FAILED: lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/clzsi2.S.o
> /usr/local/myclang/bin/clang -DVISIBILITY_HIDDEN  -fno-lto -std=c11 -fPIC -fno-builtin -fvisibility=hidden -fomit-frame-pointer -fomit-frame-pointer -DCOMPILER_RT_ARMHF_TARGET -MD -MT lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/clzsi2.S.o -MF lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/clzsi2.S.o.d -o lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/clzsi2.S.o -c /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:16:2: error: unknown directive
>  .syntax unified
>  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:33:2: error: unknown use of instruction mnemonic without a size suffix
>  mov r1, 1
>  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:35:2: error: invalid instruction mnemonic 'lsrs'
>  lsrs r2, r0, 16; movne r0, r2; addeq r1, 16
>  ^~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:35:19: error: invalid instruction mnemonic 'movne'
>  lsrs r2, r0, 16; movne r0, r2; addeq r1, 16
>                   ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:35:33: error: invalid instruction mnemonic 'addeq'
>  lsrs r2, r0, 16; movne r0, r2; addeq r1, 16
>                                 ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:36:2: error: invalid instruction mnemonic 'lsrs'
>  lsrs r2, r0, 8; movne r0, r2; addeq r1, 8
>  ^~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:36:18: error: invalid instruction mnemonic 'movne'
>  lsrs r2, r0, 8; movne r0, r2; addeq r1, 8
>                  ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:36:32: error: invalid instruction mnemonic 'addeq'
>  lsrs r2, r0, 8; movne r0, r2; addeq r1, 8
>                                ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:37:2: error: invalid instruction mnemonic 'lsrs'
>  lsrs r2, r0, 4; movne r0, r2; addeq r1, 4
>  ^~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:37:18: error: invalid instruction mnemonic 'movne'
>  lsrs r2, r0, 4; movne r0, r2; addeq r1, 4
>                  ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:37:32: error: invalid instruction mnemonic 'addeq'
>  lsrs r2, r0, 4; movne r0, r2; addeq r1, 4
>                                ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:38:2: error: invalid instruction mnemonic 'lsrs'
>  lsrs r2, r0, 2; movne r0, r2; addeq r1, 2
>  ^~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:38:18: error: invalid instruction mnemonic 'movne'
>  lsrs r2, r0, 2; movne r0, r2; addeq r1, 2
>                  ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:38:32: error: invalid instruction mnemonic 'addeq'
>  lsrs r2, r0, 2; movne r0, r2; addeq r1, 2
>                                ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzsi2.S:40:2: error: unknown use of instruction mnemonic without a size suffix
>  sub r0, r1, r0, lsr #1
>  ^
> [5/207] Building ASM object lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/clzdi2.S.o
> FAILED: lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/clzdi2.S.o
> /usr/local/myclang/bin/clang -DVISIBILITY_HIDDEN  -fno-lto -std=c11 -fPIC -fno-builtin -fvisibility=hidden -fomit-frame-pointer -fomit-frame-pointer -DCOMPILER_RT_ARMHF_TARGET -MD -MT lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/clzdi2.S.o -MF lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/clzdi2.S.o.d -o lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/clzdi2.S.o -c /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:16:2: error: unknown directive
>  .syntax unified
>  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:50:2: error: unknown use of instruction mnemonic without a size suffix
>  cmp r1, 0
>  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:51:2: error: invalid instruction mnemonic 'movne'
>  movne r0, r1
>  ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:53:2: error: invalid instruction mnemonic 'movne'
>  movne r1, 1
>  ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:54:2: error: invalid instruction mnemonic 'moveq'
>  moveq r1, 33
>  ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:56:2: error: invalid instruction mnemonic 'lsrs'
>  lsrs r2, r0, 16; movne r0, r2; addeq r1, 16
>  ^~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:56:19: error: invalid instruction mnemonic 'movne'
>  lsrs r2, r0, 16; movne r0, r2; addeq r1, 16
>                   ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:56:33: error: invalid instruction mnemonic 'addeq'
>  lsrs r2, r0, 16; movne r0, r2; addeq r1, 16
>                                 ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:57:2: error: invalid instruction mnemonic 'lsrs'
>  lsrs r2, r0, 8; movne r0, r2; addeq r1, 8
>  ^~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:57:18: error: invalid instruction mnemonic 'movne'
>  lsrs r2, r0, 8; movne r0, r2; addeq r1, 8
>                  ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:57:32: error: invalid instruction mnemonic 'addeq'
>  lsrs r2, r0, 8; movne r0, r2; addeq r1, 8
>                                ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:58:2: error: invalid instruction mnemonic 'lsrs'
>  lsrs r2, r0, 4; movne r0, r2; addeq r1, 4
>  ^~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:58:18: error: invalid instruction mnemonic 'movne'
>  lsrs r2, r0, 4; movne r0, r2; addeq r1, 4
>                  ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:58:32: error: invalid instruction mnemonic 'addeq'
>  lsrs r2, r0, 4; movne r0, r2; addeq r1, 4
>                                ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:59:2: error: invalid instruction mnemonic 'lsrs'
>  lsrs r2, r0, 2; movne r0, r2; addeq r1, 2
>  ^~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:59:18: error: invalid instruction mnemonic 'movne'
>  lsrs r2, r0, 2; movne r0, r2; addeq r1, 2
>                  ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:59:32: error: invalid instruction mnemonic 'addeq'
>  lsrs r2, r0, 2; movne r0, r2; addeq r1, 2
>                                ^~~~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/clzdi2.S:61:2: error: unknown use of instruction mnemonic without a size suffix
>  sub r0, r1, r0, lsr #1
>  ^
> [6/207] Building ASM object lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/divmodsi4.S.o
> FAILED: lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/divmodsi4.S.o
> /usr/local/myclang/bin/clang -DVISIBILITY_HIDDEN  -fno-lto -std=c11 -fPIC -fno-builtin -fvisibility=hidden -fomit-frame-pointer -fomit-frame-pointer -DCOMPILER_RT_ARMHF_TARGET -MD -MT lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/divmodsi4.S.o -MF lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/divmodsi4.S.o.d -o lib/builtins/CMakeFiles/clang_rt.builtins-armhf.dir/arm/divmodsi4.S.o -c /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:24:2: error: unknown directive
>  .syntax unified
>  ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:28:1: error: unexpected token at start of statement
> @ int __divmodsi4(int divident, int divisor, int *remainder)
> ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:29:1: error: unexpected token at start of statement
> @ Calculate the quotient and remainder of the (signed) division. The return
> ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:30:1: error: unexpected token at start of statement
> @ value is the quotient, the remainder is placed in the variable.
> ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:46:11: error: Invalid rounding mode.
>     push {r4-r7, lr} ; add r7, sp, #12
>           ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:46:36: error: unknown token in expression
>     push {r4-r7, lr} ; add r7, sp, #12
>                                    ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:49:5: error: invalid instruction mnemonic 'eor'
>     eor r4, r0, r1
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:50:5: error: unknown use of instruction mnemonic without a size suffix
>     mov r5, r0
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:51:5: error: unknown use of instruction mnemonic without a size suffix
>     mov r6, r2
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:53:5: error: invalid instruction mnemonic 'eor'
>     eor ip, r0, r0, asr #31
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:54:5: error: invalid instruction mnemonic 'eor'
>     eor lr, r1, r1, asr #31
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:55:5: error: unknown use of instruction mnemonic without a size suffix
>     sub r0, ip, r0, asr #31
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:56:5: error: unknown use of instruction mnemonic without a size suffix
>     sub r1, lr, r1, asr #31
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:58:5: error: invalid instruction mnemonic 'bl'
>     bl __udivmodsi4
>     ^~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:60:5: error: invalid instruction mnemonic 'ldr'
>     ldr r1, [r6]
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:61:5: error: invalid instruction mnemonic 'eor'
>     eor r0, r0, r4, asr #31
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:62:5: error: invalid instruction mnemonic 'eor'
>     eor r1, r1, r5, asr #31
>     ^~~
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:63:5: error: unknown use of instruction mnemonic without a size suffix
>     sub r0, r0, r4, asr #31
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:64:5: error: unknown use of instruction mnemonic without a size suffix
>     sub r1, r1, r5, asr #31
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:65:5: error: unknown use of instruction mnemonic without a size suffix
>     str r1, [r6]
>     ^
> /home/llvm_all/llvm/projects/compiler-rt/lib/builtins/arm/divmodsi4.S:66:10: error: Invalid rounding mode.
>     pop {r4-r7, pc}
>
>
>
>
>
>
>
>
>
>
>
> On 04.12.2018 15:54, Peter Smith via llvm-dev wrote:
>
> Hello,
>
> Just a few quick observations.
> - It looks like you may have downloaded the linux arm toolchain. For bare metal you probably wanted the Arm embedded toolchain, https://developer.arm.com/open-source/gnu-toolchain/gnu-rm
> -- That toolchain will have newlib rather than glibc, I don't know whether it will have one pre-compiled for v4 though. If not you may have to find an older toolchain or build newlib youtself.
> - The bare-metal driver in clang (arm-none-eabi) is not multilib aware and won't put the paths to the libraries on the link line, the -L flag
> -- I have found that following the samples in the gnu embedded toolchain with gcc using the -v flag to get the paths it is using, then use these with lld.
>
> If you can let us know what problems you are seeing building compiler-rt then we may be able to help. I'm not sure there is anyone building it for arm v4 so you may be hitting new problems. I'm away at a conference today and tomorrow but I can try later in the week.
>
> Peter
>
> On Tue, 4 Dec 2018 at 12:21, cscheuer via llvm-dev <llvm-dev at lists.llvm.org> wrote:
>
> I am currently trying to compile a pretty simple program to work on an
> experimental board. It contains an (FPGA-version of) an ARMv4 processor.
> So basically, I try this (on my Ubuntu 18.04.1 LTS):
> clang -v --target=arm-none-eabi -c barehello.c -o barehelloCLANG.o
> clang -v --target=arm-none-eabi -c io.c -o io.o
> clang -v --target=arm-none-eabi barehelloCLANG.o io.o -o
> helloCLANGstatic -static -fuse-ld=lld
>
> Which results in
>
> clang version 8.0.0 (https://git.llvm.org/git/clang.git/
> a152c7a4b7ba8f4cb9532ead9a38a7121db43d50)
> (https://git.llvm.org/git/llvm.git/
> 1959ce6f3e01241919968ac1911fd45660239d23)
> Target: arm-none-unknown-eabi
> Thread model: posix
> InstalledDir: /usr/local/my_clang/bin
>   "/usr/local/my_clang/bin/ld.lld" barehelloCLANG.o io.o -Bstatic
> -L/usr/local/my_clang/lib/clang/8.0.0/lib/baremetal -lc -lm
> -lclang_rt.builtins-arm.a -o helloCLANGstatic
> ld.lld: error: unable to find library -lc
> ld.lld: error: unable to find library -lm
> ld.lld: error: unable to find library -lclang_rt.builtins-arm.a
> clang-8: error: ld.lld command failed with exit code 1 (use -v to see
> invocation)
>
> on the linking part. I downloaded a sysroot from
> https://developer.arm.com/open-source/gnu-toolchain/gnu-a/downloads/8-2-2018-08
> and tried to include it via --sysroot=/my/path/to/it, but clang acted
> unimpressed with the same errors. So I'm missing clang_rt.builtins-arm.a
> I guess, but that does not exist on my system.
> So next, I tried basically every version of "how to cross-compile
> llvm/clang/compiler-rt" That google came up with, but was not able to
> get a single one to actually work. Any ideas how to get this running?
> Thanks in advance!
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
>
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
>
>