fpetrogalli added a comment. @barannikov88 - Imam stuck with an incomplete explanation:
The issue raised by @mgorny is about stand-alone <https://llvm.org/docs/GettingStarted.html#stand-alone-builds> builds. In this build configuration, clang is built separately from LLVM, which is first build and installed in a folder. When clang is build as a stand-alone project, clang does not have access to the cmake configuration of LLVM. Therefore it knows nothing about the tablegen target `RISCVTargetParserTableGen`. The's why we see the following error when building stand-alone clang on `main`: CMake Error at /Users/fpetrogalli/projects/cpu-defs/install/lib/cmake/llvm/AddLLVM.cmake:536 (add_dependencies): The dependency target "RISCVTargetParserTableGen" of target "obj.clangBasic" does not exist. Call Stack (most recent call first): cmake/modules/AddClang.cmake:106 (llvm_add_library) lib/Basic/CMakeLists.txt:40 (add_clang_library) I do not know why `LLVMTargetParser` (which is also specified in the cmake configuration of llvm) is instead recognised as a valid dependencies of clang on some LLVM library. Maybe because cmake looks in the prefix folder where LLVM was installed and finds the object file of the library? FWIW, I was able to reproduce the issue reported by @mgorny via the following script when run on `main`: #!/bin/sh build_llvm=`pwd`/build-llvm build_clang=`pwd`/build-clang installprefix=`pwd`/install llvm=`pwd`/llvm-project mkdir -p $build_llvm mkdir -p $installprefix cmake -G Ninja -S $llvm/llvm -B $build_llvm \ -DLLVM_INSTALL_UTILS=ON \ -DCMAKE_INSTALL_PREFIX=$installprefix \ -DCMAKE_BUILD_TYPE=Release ninja -C $build_llvm install cmake -G Ninja -S $llvm/clang -B $build_clang \ -DLLVM_EXTERNAL_LIT=$build_llvm/utils/llvm-lit \ -DLLVM_ROOT=$installprefix Given it was an issue that cmake itself was reporting (and not a build time failure), I thought that its disappearance after applying this patch was a signal thatI was doing the right thing. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D141581/new/ https://reviews.llvm.org/D141581 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
