Many "not found"

Clang Frontend Building Clang
1

While following instructions at get_started page link below The cmake attempt shown below resulted in many “not found” messages as shown below in the beginning of the output log. Kindly Advise Thank You Kindly

https://clang.llvm.org/get_started.html
cmake -DLLVM_ENABLE_PROJECTS=clang -G “Visual Studio 17 2022” -A x64 -Thost=x64 …\llvm

cmake -DLLVM_ENABLE_PROJECTS=clang -G “Visual Studio 17 2022” -A x64 -Thost=x64 …\llvm
– Selecting Windows SDK version 10.0.19041.0 to target Windows 10.0.19044.
– The C compiler identification is MSVC 19.34.31933.0
– The CXX compiler identification is MSVC 19.34.31933.0
– The ASM compiler identification is MSVC
– Found assembler: C:/Program Files/Microsoft Visual Studio/2022/Preview/VC/Tools/MSVC/14.34.31933/bin/Hostx64/x64/cl.exe
– Detecting C compiler ABI info
– Detecting C compiler ABI info - done
– Check for working C compiler: C:/Program Files/Microsoft Visual Studio/2022/Preview/VC/Tools/MSVC/14.34.31933/bin/Hostx64/x64/cl.exe - skipped
– Detecting C compile features
– Detecting C compile features - done
– Detecting CXX compiler ABI info
– Detecting CXX compiler ABI info - done
– Check for working CXX compiler: C:/Program Files/Microsoft Visual Studio/2022/Preview/VC/Tools/MSVC/14.34.31933/bin/Hostx64/x64/cl.exe - skipped
– Detecting CXX compile features
– Detecting CXX compile features - done
– bolt project is disabled
– clang project is enabled
– clang-tools-extra project is disabled
– compiler-rt project is disabled
– cross-project-tests project is disabled
– libc project is disabled
– libclc project is disabled
– lld project is disabled
– lldb project is disabled
– mlir project is disabled
– openmp project is disabled
– polly project is disabled
– pstl project is disabled
– flang project is disabled
– Found Python3: C:/Users/Bernard/AppData/Local/Programs/Python/Python311/python.exe (found suitable version “3.11.0”, minimum required is “3.6”) found components: Interpreter
– Looking for dlfcn.h
– Looking for dlfcn.h - not found
– Looking for errno.h
– Looking for errno.h - found
– Looking for fcntl.h
– Looking for fcntl.h - found
– Looking for link.h
– Looking for link.h - not found
– Looking for malloc/malloc.h
– Looking for malloc/malloc.h - not found
– Looking for signal.h
– Looking for signal.h - found
– Looking for sys/ioctl.h
– Looking for sys/ioctl.h - not found
– Looking for sys/mman.h
– Looking for sys/mman.h - not found
– Looking for sys/param.h
– Looking for sys/param.h - not found
– Looking for sys/resource.h
– Looking for sys/resource.h - not found

2

As long as the cmake process finishes successfully these messages are nothing to worry about.

What they are doing is checking for something, then if it is found, some part of llvm may use it. If it isn’t found, we’ll do something else instead.

(given that you’re on Windows, a lot of those Unix-esque headers are unlikely to exist so this is to be expected)

If there’s no alternative you’ll get an error, usually with the literal text “error: ”. That’s what you should pay attention to.