[llvm-dev] Coding standards: duplicating method comments?

[Alex Bradbury via llvm-dev]

A quick coding standards question. The current coding standards doc
has helpful guidance on Doxygen comments and the like:
https://llvm.org/docs/CodingStandards.html#source-code-formatting

One aspect which isn't explicit is the policy on duplicating code
comments for subclasses. To modify an example from that doc:

"""
// In Something.h:

/// An abstraction for some complicated thing.
class Something {
public:
  /// Does foo and bar.
  virtual void fooBar();
};
"""

Suppose we define TargetSomething.h, and give the same comment for fooBar there:
"""
class TargetSomething : public Something {
public:
  /// Does foo and bar.
  void fooBar() override;
};
"""

Is this bad style? It seems the current codebase is inconsistent on
this point. The upside of such duplication is that it reduces the need
to cross-reference to other files when using a dumb editor. The
disadvantage is that duplicated comments add maintenance burden just
like duplicated code.

Thanks,

Alex