[llvm] [offload][runtimes] Forward user-provided system configuration. (PR #96303)

[Joseph Huber via llvm-commits]

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@@ -499,28 +508,25 @@ if(build_runtimes)
       endif()
       list(APPEND libc_cmake_args "-DRUNTIMES_nvptx64-nvidia-cuda_LLVM_LIBC_FULL_BUILD=ON")
     endif()
-    # The `libc` project may require '-DCUDAToolkit_ROOT' in GPU mode.
-    if(CUDAToolkit_ROOT)
-      list(APPEND libc_cmake_args "-DCUDAToolkit_ROOT=${CUDAToolkit_ROOT}")
-    endif()
     if(TARGET clang-offload-packager)
       list(APPEND extra_deps clang-offload-packager)
     endif()
   endif()
   if(LLVM_LIBC_FULL_BUILD)
     list(APPEND libc_cmake_args "-DLLVM_LIBC_FULL_BUILD=ON")
   endif()
+
   if(NOT LLVM_RUNTIME_TARGETS)
     runtime_default_target(
       DEPENDS ${builtins_dep} ${extra_deps}
-      CMAKE_ARGS ${libc_cmake_args}
+      CMAKE_ARGS ${extra_cmake_args} ${libc_cmake_args}
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jhuber6 wrote:

If we have `extra_cmake_args` now can we just merge `libc_cmake_args` into it?

https://github.com/llvm/llvm-project/pull/96303