compile error when compile libc

[MayhXiaodi]

I build my project use:
cmake -G "Unix Makefiles" ../llvm \

          -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra;compiler-rt;**libc**;libcxx;libcxxabi;lld"        \

          -DLLVM_BUILD_EXAMPLES=ON -DLLVM_TARGETS_TO_BUILD="RISCV"                              \

          -DCMAKE_BUILD_TYPE=Release -DLLVM_ENABLE_ASSERTIONS=ON                                 \

          -DLLVM_DEFAULT_TARGET_TRIPLE="riscv64-unknown-linux-gnu"                                           \

          -DCMAKE_INSTALL_PREFIX=/home/mingjun/opt/rvv-llvm

but when compile, a fatal error:
[ 53%] Building CXX object projects/libc/utils/HdrGen/CMakeFiles/obj.libc-hdrgen.dir/PublicAPICommand.cpp.o
/home/mingjun/work/rvv-llvm/rvv-llvm/libc/utils/HdrGen/PublicAPICommand.cpp:11:10: fatal error: utils/LibcTableGenUtil/APIIndexer.h: No such file or directory
11 | #include "utils/LibcTableGenUtil/APIIndexer.h"
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.

I would like to ask, have you encountered this problem when compiling?

[xingmingjie]

Tried to build rvv-iscas branch with your cmake command, but there's no error. Please make sure that your source code is complete, and the file APIIndexer.h is available.

[edwincg]

Hello,
I also got hit by this exact same problem when building (llvmorg-12.0.0-rc5 tag). So you're not the only one.

I'm attempting to bootstrap the build of the whole project: first built clang and now I'm trying to build everything with the new compiler. I got past the problem above problem by the awful hack of copying the missing header to a findable place, but while that error went away, I was shortly welcomed by:
make[2]: *** No rule to make target projects/libc/src/math/CMakeFiles/libc.src.math.truncl.dir/truncl.cpp.o', needed by projects/libc/lib/libllvmlibm.a'. Stop.
So more than one thing is off.
This is my first experience with LLVM, I'll be happy to get some help. For what it's worth, my configuration step was:

cmake -G "Unix Makefiles"
-DDEFAULT_SYSROOT="/"
-DRUN_HAVE_STD_REGEX=1
-DRUN_HAVE_POSIX_REGEX=0
-DBUILD_SHARED_LIBS:BOOL=OFF
-DCMAKE_CROSSCOMPILING=0
-DCMAKE_BUILD_TYPE=RelWithDebInfo
-DCMAKE_CXX_STANDARD=14
-DCMAKE_C_COMPILER=$(which clang)
-DCMAKE_CXX_COMPILER=$(which clang++)
-DCMAKE_ASM_COMPILER_AR:FILEPATH=$(which llvm-ar)
-DCMAKE_ASM_COMPILER_RANLIB:FILEPATH=$(which llvm-ranlib)
-DCMAKE_INSTALL_PREFIX:PATH=${install_dir}
-DCMAKE_OBJCOPY:FILEPATH=$(which llvm-objcopy)
-DCMAKE_OBJCOPY:FILEPATH=$(which llvm-objdump)
-DCMAKE_LINKER:FILEPATH=$(which lld)
-DCLANG_DEFAULT_CXX_STDLIB:STRING="libc++"
-DCLANG_DEFAULT_LINKER:STRING="lld"
-DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra;polly;parallel-libs;pstl;openmp;libunwind;lldb;debuginfo-tests;libclc;libc"
-DLLVM_ENABLE_LLD:BOOL=ON
-DLLVM_TARGETS_TO_BUILD:STRING=X86
-DLLVM_ENABLE_LIBCXX:BOOL=ON
-DLLVM_INSTALL_UTILS=ON
-DLLVM_BUILD_DOCS:BOOL=OFF
-DLLVM_BUILD_EXAMPLES:BOOL=ON
-DLLVM_OPTIMIZED_TABLEGEN:BOOL=OFF
-DLLVM_ENABLE_BINDINGS=OFF
-DLLDB_TEST_C_COMPILER:PATH=$(which clang)
-DLLDB_TEST_CXX_COMPILER:PATH=$(which clang++)
-DLLDB_USING_LIBSTDCXX:INTERNAL=1
-DPYTHON_EXECUTABLE=$(which python3)
-DCUDA_ATTACH_VS_BUILD_RULE_TO_CUDA_FILE:BOOL=OFF
-DLLDB_TOOL_LLDB_VSCODE_BUILD:BOOL=OFF
../llvm-project/llvm

[alextsao1999]

I build my project use:
cmake -G "Unix Makefiles" ../llvm \

          -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra;compiler-rt;**libc**;libcxx;libcxxabi;lld"        \

          -DLLVM_BUILD_EXAMPLES=ON -DLLVM_TARGETS_TO_BUILD="RISCV"                              \

          -DCMAKE_BUILD_TYPE=Release -DLLVM_ENABLE_ASSERTIONS=ON                                 \

          -DLLVM_DEFAULT_TARGET_TRIPLE="riscv64-unknown-linux-gnu"                                           \

          -DCMAKE_INSTALL_PREFIX=/home/mingjun/opt/rvv-llvm

but when compile, a fatal error:
[ 53%] Building CXX object projects/libc/utils/HdrGen/CMakeFiles/obj.libc-hdrgen.dir/PublicAPICommand.cpp.o
/home/mingjun/work/rvv-llvm/rvv-llvm/libc/utils/HdrGen/PublicAPICommand.cpp:11:10: fatal error: utils/LibcTableGenUtil/APIIndexer.h: No such file or directory
11 | #include "utils/LibcTableGenUtil/APIIndexer.h"
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.

I would like to ask, have you encountered this problem when compiling?

I have tried to build it again, but the error did not reappear, can you provide your branch or did you pull the latest version?

[edwincg]

Hello, thank you for following up.
The source tree is a result of:
git clone https://github.com/llvm/llvm-project.git
git checkout llvmorg-12.0.0-rc5
I have not touched the source tree.

[alextsao1999]

Hello, thank you for following up.
The source tree is a result of:
git clone https://github.com/llvm/llvm-project.git
git checkout llvmorg-12.0.0-rc5
I have not touched the source tree.

When I was built llvm with -DLLVM_ENABLE_LLD:BOOL=ON, cmake reported "Host compiler does not support '-fuse-ld=lld'",
After removing the option, I can compile llvm sucessfully...
This is my command line, similar to yours

cmake -GNinja -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=$HOME/prebuild/llvm -DCLANG_DEFAULT_CXX_STDLIB="libc++" -DCLANG_DEFAULT_LINKER=lld -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra;polly;parallel-libs;pstl;openmp;libunwind;lldb;debuginfo-tests;libclc;libc;libcxxabi;libcxx;lld" -DLLVM_ENABLE_LIBCXX=ON -DLLVM_INSTALL_UTILS=ON -DLLVM_BUILD_DOCS=ON -DLLVM_OPTIMIZED_TABLEGEN=ON -DLLVM_ENABLE_BINDINGS=OFF -DLLDB_USING_LIBSTDCXX:INTERNAL=1 -DPYTHON_EXECUTABLE=$(which python3) -DLLDB_TOOL_LLDB_VSCODE_BUILD=OFF -DRUN_HAVE_STD_REGEX=1 -DRUN_HAVE_POSIX_REGEX=0 -DCMAKE_C_COMPILER=clang ../llvm

[mjj29]

I have exactly the same problem building libc, in my case cross compiling for arm with:

../cmake/bin/cmake -G "Unix Makefiles" -DCMAKE_INSTALL_PREFIX=/ -DCMAKE_BUILD_TYPE=Release -DLLVM_BUILD_DOCS=OFF -DCMAKE_CROSSCOMPILING=True -DLLVM_DEFAULT_TARGET_TRIPLE=arm-linux-gnueabihf -DLLVM_TARGET_ARCH=ARM -DLLVM_TARGETS_TO_BUILD=ARM -DLLVM_ENABLE_PROJECTS="libc" -DLLVM_LIBC_ENABLE_LINTING=OFF ../llvm-project-llvmorg-12.0.0/llvm