[clang] [Clang] suggest headers on undeclared errors (PR #140247)

[via cfe-commits]

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@@ -14,6 +14,8 @@
 #include "clang/Basic/DiagnosticParse.h"
 #include "clang/Parse/Parser.h"
 #include "clang/Sema/ParsedTemplate.h"
+#include "clang/Tooling/Inclusions/StandardLibrary.h"
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cor3ntin wrote:

Sure, but we want to rewrite anyway. The implementation (StandardLibrary.cpp) seems fairly inefficient. We should try to TableGen a trie and store version information in there, have some support for typo correction, etc

https://github.com/llvm/llvm-project/pull/140247