[all-commits] [llvm/llvm-project] a35a3b: [libc][cmake] Tidy compiler includes (#66783)

[Guillaume Chatelet via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: a35a3b75b219247eb9ff6784d1a0fe562f72d415
      https://github.com/llvm/llvm-project/commit/a35a3b75b219247eb9ff6784d1a0fe562f72d415
  Author: Guillaume Chatelet <gchatelet at google.com>
  Date:   2023-09-19 (Tue, 19 Sep 2023)

  Changed paths:
    M libc/CMakeLists.txt
    M libc/cmake/modules/LLVMLibCObjectRules.cmake
    M libc/cmake/modules/LLVMLibCTestRules.cmake
    M libc/utils/HdrGen/CMakeLists.txt
    M libc/utils/LibcTableGenUtil/CMakeLists.txt

  Log Message:
  -----------
  [libc][cmake] Tidy compiler includes (#66783)

We want to activate `llvm-header-guard` (#66477) but the current CMake
configuration includes paths that should be `isystem`. This PR restricts
the number of `-I` passed to the clang command line and correctly marks
the llvm libc include path as `isystem`.