[clang] [analyzer][CTU] Macro expansions for imported translation units (PR #176126)

[Vladimir Vuksanovic via cfe-commits]

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@@ -186,14 +186,14 @@ class CrossTranslationUnitContext {
   /// Emit diagnostics for the user for potential configuration errors.
   void emitCrossTUDiagnostics(const IndexError &IE);
 
-  /// Returns the MacroExpansionContext for the imported TU to which the given
-  /// source-location corresponds.
-  /// \p ToLoc Source location in the imported-to AST.
-  /// \note If any error happens such as \p ToLoc is a non-imported
+  /// Returns the MacroExpansionContext for the imported TU and the location in
+  /// the imported-from AST to which the given source-location corresponds. \p
+  /// ToLoc Source location in the imported-to AST. \note If any error happens
+  /// such as \p ToLoc is a non-imported
   ///       source-location, empty is returned.
   /// \note Macro expansion tracking for imported TUs is not implemented yet.
   ///       It returns empty unconditionally.
-  std::optional<clang::MacroExpansionContext>
+  std::optional<std::pair<MacroExpansionContext, SourceLocation>>
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vvuksanovic wrote:

It now also returns the corresponding `SourceLocation` in the 'imported from' context. The `MacroExpansionContext` for each TU contains locations in its original context, but this function receives 'imported to' `SourceLocation`s. The getters in `MacroExpansionContext` also expect to receive locations in the 'imported from' context, so they have to be translated somewhere.

I am not sure how this API was intended to be used

https://github.com/llvm/llvm-project/pull/176126