In addition to what others have said, C and C++ rely on a textual macro preprocessor and text-based #include, which can lead to a lot of annoying code-breakage

In addition to what others have said, C and C++ rely on a textual macro preprocessor and text-based #include, which can lead to a lot of annoying code-breakage when refactoring. Automated tools can't parse C/C++ unless they're effectively built on top of a full compiler; even building a complete C preprocessor is an extremely non-trivial task. (Many newer C++ code-bases discourage relying on the preprocessor, but that only goes so far.)