[clang-tools-extra] [clangd] fix wrong resouce-dir (PR #203332)

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playerC wrote:

Hello @HighCommander4 

Great thanks for your reply.

> I thought it was referring to the compiler used to build the code (from the compile command, or [this `Compiler` config option](https://clangd.llvm.org/config#compiler)),

You are right , I just use this config value. 

> but I now see that you're actually adding a new config option to customize the path used to determine the resource dir.

That option the same one, just get the compiler value out.

>Or, if you prefer the config file over command line options, here is a way to override the resource using existing config options

Yes , I know it , we can change the options value to correct it .

But I think, clangd should be ready to use after install with default options. If something wrong , clangd could tell you
what is wrong.

And I have read more document, that says : clangd must set `resource-dir` to the same version of clang which it depend on.

So I think using the compiler to detect resource-dir is not correct.

clangd may be need a mechanism to check `resource-dir`  , and give user suggestion to set it , if something wrong.

Do you have any suggestion?

https://github.com/llvm/llvm-project/pull/203332