[clang] ✨ [Sema, Lex, Parse] Preprocessor embed in C and C++ (and Obj-C and Obj-C++ by-proxy) (PR #68620)

[Fangrui Song via cfe-commits]

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@@ -816,6 +821,14 @@ will be ignored}]>;
 def L : JoinedOrSeparate<["-"], "L">, Flags<[RenderJoined]>, Group<Link_Group>,
     Visibility<[ClangOption, FlangOption]>,
     MetaVarName<"<dir>">, HelpText<"Add directory to library search path">;
+def embed_dir : JoinedOrSeparate<["-"], "embed-dir">,
+    Flags<[RenderJoined]>, Group<EmbedPath_Group>,
+    Visibility<[ClangOption, CC1Option, CC1AsOption, FlangOption, FC1Option]>,
+    MetaVarName<"<dir>">, HelpText<"Add directory to embed search path">;
+def embed_dir_EQ : JoinedOrSeparate<["-"], "embed-dir=">,
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MaskRay wrote:

`-e` is a driver option, so `-eembed-dir-with-typo` is recognized. Better to use `--embed-dir=`. Please don't support `*Separate<...>` for new options.

https://github.com/llvm/llvm-project/pull/68620