CMake fails on mlir when building for Xcode

[Iritscen]

When issuing this command: cmake -B build-Xcode -G "Xcode" -S llvm -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra;mlir" -DCMAKE_BUILD_TYPE=Debug -DLLVM_ENABLE_ASSERTIONS=OFF -DCMAKE_OSX_SYSROOT=$(xcrun --sdk macosx --show-sdk-path)

I get this error:

CMake Error in /path/to/llvm-project/mlir/include/mlir/Dialect/Arith/IR/CMakeLists.txt:
  The custom command generating

    /path/to/llvm-project/build-Xcode/tools/mlir/include/mlir/Dialect/Arith/IR/ArithOpsEnums.h.inc

  is attached to multiple targets:

    MLIRArithOpsIncGen
    MLIRArithOpsInterfacesIncGen

  but none of these is a common dependency of the other(s).  This is not
  allowed by the Xcode "new build system".

Removing "mlir" from -DLLVM_ENABLE_PROJECTS allows CMake to proceed successfully. This is with CMake version 3.31.7.

[llvmbot]

@llvm/issue-subscribers-mlir

Author: None (Iritscen)

When issuing this command: `cmake -B build-Xcode -G "Xcode" -S llvm -DLLVM_ENABLE_PROJECTS="clang;clang-tools-extra;mlir" -DCMAKE_BUILD_TYPE=Debug -DLLVM_ENABLE_ASSERTIONS=OFF -DCMAKE_OSX_SYSROOT=$(xcrun --sdk macosx --show-sdk-path)`

I get this error:

CMake Error in /path/to/llvm-project/mlir/include/mlir/Dialect/Arith/IR/CMakeLists.txt:
  The custom command generating

    /path/to/llvm-project/build-Xcode/tools/mlir/include/mlir/Dialect/Arith/IR/ArithOpsEnums.h.inc

  is attached to multiple targets:

    MLIRArithOpsIncGen
    MLIRArithOpsInterfacesIncGen

  but none of these is a common dependency of the other(s).  This is not
  allowed by the Xcode "new build system".

Removing "mlir" from -DLLVM_ENABLE_PROJECTS allows CMake to proceed successfully. This is with CMake version 3.31.7.