[clang] [clang] Limit file location search for macro argument locations (PR #232469)

[Raphael Isemann via cfe-commits]

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@@ -1211,9 +1212,14 @@ class SourceManager : public RefCountedBase<SourceManager> {
   /// Given \p Loc, if it is a macro location return the expansion
   /// location or the spelling location, depending on if it comes from a
   /// macro argument or not.
-  SourceLocation getFileLoc(SourceLocation Loc) const {
+  ///
+  /// If resolving \p Loc requires walking through more than \p MaxDepth
+  /// macro expansions, an invalid location is returned instead.
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Teemperor wrote:

note: an optional<SourceLocation> feels nicer to me, but the rest of the file already uses the invalid SourcdLocation as a magic return value.

https://github.com/llvm/llvm-project/pull/232469