[libc] [llvm] [libc] Support multilib with runtimes build (PR #115357)

[Joseph Huber via llvm-commits]

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@@ -248,10 +248,17 @@ foreach(config_path IN LISTS LIBC_CONFIG_JSON_FILE_LIST)
   load_libc_config(${config_path}/config.json ${cmd_line_conf})
 endforeach()
 
+if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR)
+  set(LIBC_TARGET_SUBDIR ${LLVM_DEFAULT_TARGET_TRIPLE})
+  if(LIBC_LIBDIR_SUBDIR)
+    string(APPEND LIBC_TARGET_SUBDIR /${LIBC_LIBDIR_SUBDIR})
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jhuber6 wrote:

So things will be installed in `lib/x86_64-unknown-linux-gnu/<feature>` for example? How does the compiler know where to find it.

https://github.com/llvm/llvm-project/pull/115357