Because the Clang Static Analyzer is “built on Clang,” one might assume that its analyses are performed on a representation that is faithful to both the Clang AST and the generated LLVM IR. The takeaway here is that the Clang AST is missing information that is invented by the LLVM IR code generator, but LLVM IR is also missing information that is destroyed by said code generator. Depending on your system and setup, this might mean Apple Clang, Homebrew Clang, vcpkg Clang, one of the many Clangs available in Debian’s package manager, or maybe a custom-built one.