llvm-project

07ffb7e2 - [lldb][ClangASTImporter] Import record layouts from origin if available (#83295)

[lldb][ClangASTImporter] Import record layouts from origin if available (#83295) Layout information for a record gets stored in the `ClangASTImporter` associated with the `DWARFASTParserClang` that originally parsed the record. LLDB sometimes moves clang types from one AST to another (in the reproducer the origin AST was a precompiled-header and the destination was the AST backing the executable). When clang then asks LLDB to `layoutRecordType`, it will do so with the help of the `ClangASTImporter` the type is associated with. If the type's origin is actually in a different LLDB module (and thus a different `DWARFASTParserClang` was used to set its layout info), we won't find the layout info in our local `ClangASTImporter`. In the reproducer this meant we would drop the alignment info of the origin type and misread a variable's contents with `frame var` and `expr`. There is logic in `ClangASTSource::layoutRecordType` to import an origin's layout info. This patch re-uses that infrastructure to import an origin's layout from one `ClangASTImporter` instance to another. rdar://123274144