[libclc] [libclc] Initial support for cross-compiling OpenCL libraries (PR #174022)

[Matt Arsenault via cfe-commits]

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@@ -454,10 +454,22 @@ function(add_libclc_builtin_set)
 
     set( obj_suffix ${ARG_ARCH_SUFFIX}.bc )
     set( libclc_builtins_lib ${LIBCLC_OUTPUT_LIBRARY_DIR}/${obj_suffix} )
-    add_custom_command( OUTPUT ${libclc_builtins_lib}
-      COMMAND ${prepare_builtins_exe} -o ${libclc_builtins_lib} ${builtins_opt_lib}
-      DEPENDS ${builtins_opt_lib} ${builtins_opt_lib_tgt} ${prepare_builtins_target}
-    )
+    if( TARGET prepare_builtins )
+      # FIXME: Is this utility even necessary? The `-mlink-builtin-bitcode`
+      # option used to link the library in discards the modified linkage.
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arsenm wrote:

This is probably a leftover from before we did that. Also, I thought there was at least one other hack in prepare-builtins 

https://github.com/llvm/llvm-project/pull/174022