[libc] [llvm] [libc] Build the GPU during the projects setup like libc-hdrgen (PR #84667)

[via llvm-commits]

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@@ -60,6 +60,10 @@ if(LLVM_LIBC_FULL_BUILD OR LLVM_LIBC_GPU_BUILD)
     message(STATUS "Will use ${LIBC_HDRGEN_EXE} for libc header generation.")
   endif()
 endif()
+# We will build the GPU utilities if we are not doing a runtimes build.
+if((LIBC_TARGET_OS_IS_GPU OR LLVM_LIBC_GPU_BUILD) AND NOT LLVM_RUNTIMES_BUILD)
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lntue wrote:

Why do you have to skip this when `LLVM_RUNTIMES_BUILD` is set?

https://github.com/llvm/llvm-project/pull/84667