[clang-tools-extra] [include-cleaner] Handle symbols from system headers. (PR #66089)

[kadir çetinkaya via cfe-commits]

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@@ -188,6 +290,20 @@ llvm::SmallVector<Hinted<Header>> findHeaders(const SymbolLocation &Loc,
     OptionalFileEntryRef FE = SM.getFileEntryRefForID(FID);
     if (!FE)
       return {};
+
+    if (SrcMgr::isSystem(
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kadircet wrote:

i am afraid this check might be overly strict, maybe drop this initially and see if we have too many false-positives?

https://github.com/llvm/llvm-project/pull/66089