[clang] [clang][Sema] Suggest/Hint Standard Library Include File (PR #146227)

[via cfe-commits]

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@@ -3613,6 +3613,16 @@ class Sema final : public SemaBase {
                                ParsedType &SuggestedType,
                                bool IsTemplateName = false);
 
+  // Try to suggest the missing standard library include files
+  //
+  // \param SymbolName the symbol name like 'cout'
+  // \param SourceLocation the location of the note being emitted
+  // \param Namespace the namespace that must end with ::, so like 'std::'
+  void NoteStandardIncludes(StringRef SymbolName, SourceLocation IILoc,
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Mr-Anyone wrote:

FYI, the interface in `clangToolingInclusionsStdlib` requires the inclusion of `::`, so `Namesace+SymbolName` gives you the full name. I am fine with removing the inclusion of `::` at the end. 

https://github.com/llvm/llvm-project/pull/146227