[llvm] [llvm] Fix cmake string expansion in CrossCompile.cmake (PR #138901)

[Petr Hosek via llvm-commits]

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@@ -83,9 +83,9 @@ function(llvm_create_cross_target project_name target_name toolchain buildtype)
 
   add_custom_command(OUTPUT ${${project_name}_${target_name}_BUILD}/CMakeCache.txt
     COMMAND ${CMAKE_COMMAND} -G "${CMAKE_GENERATOR}"
-        -DCMAKE_MAKE_PROGRAM="${CMAKE_MAKE_PROGRAM}"
-        -DCMAKE_C_COMPILER_LAUNCHER="${CMAKE_C_COMPILER_LAUNCHER}"
-        -DCMAKE_CXX_COMPILER_LAUNCHER="${CMAKE_CXX_COMPILER_LAUNCHER}"
+        "-DCMAKE_MAKE_PROGRAM=${CMAKE_MAKE_PROGRAM}"
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petrhosek wrote:

Do you have an example where you'd want to pass flags to the native build system?

https://github.com/llvm/llvm-project/pull/138901