CMake Warning: Manually-specified variables

Runtimes OpenMP
1

During a build I get:

CMake Warning:
  Manually-specified variables were not used by the project:

    COMPILER_RT_BUILD_BUILTINS
    LLVM_CONFIG_PATH
    LLVM_ENABLE_PROJECTS_USED

Here’s my CMake invocation:

cmake -S llvm -B /path/to/llvm-build -G Ninja -DCMAKE_BUILD_TYPE=Release \
        -DCMAKE_INSTALL_PREFIX=/path/to/dev/clang \
        -DLLVM_ENABLE_PROJECTS="clang;lld" \
        -DLLVM_ENABLE_RUNTIMES="openmp;libcxx;libcxxabi" \
        -DLIBOMPTARGET_ENABLE_DEBUG=ON \
        -DGCC_INSTALL_PREFIX=/path/to/GCC

Should I just go on disregarding CMake warnings?

2

LLVM_ENABLE_RUNTIMES will add a couple of CMake variables when it invokes the runtime build. Since that invocation is generic to every runtime project in LLVM, it has some variables that are not used by OpenMP. Simply ignore them.

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3

It is a little annoying though. Is it possible to make the runtimes invocation pass --no-warn-unused-cli to CMake?

4

That is feasible.

5

I pushed a patch to hopefully fix this. Runtimes now passes -no-warn-unused-cli.

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