[PATCH] D150411: [NFC][Clang][Coverity] Fix Static Code Analysis Concerns with copy without assign

[Soumi Manna via Phabricator via cfe-commits]

Manna added inline comments.


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Comment at: clang/include/clang/Sema/Sema.h:1789-1791
+    SemaDiagnosticBuilder &operator=(SemaDiagnosticBuilder &&D) = delete;
     SemaDiagnosticBuilder(const SemaDiagnosticBuilder &) = default;
+    SemaDiagnosticBuilder &operator=(const SemaDiagnosticBuilder &) = delete;
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tahonermann wrote:
> aaronpuchert wrote:
> > Manna wrote:
> > > @tahonermann This is follow-up comments from https://reviews.llvm.org/D149718?id=519331#inline-1452044. 
> > > 
> > > >>This change still declares a move assignment operator, but doesn't provide a definition. The move constructor is implemented in clang/lib/Sema/Sema.cpp, so I would expect to see the move assignment operator definition provided there as well.
> > > 
> > > I tried to define move assignment operator in ` clang/lib/Sema/Sema.cpp` but it failed because class Sema has deleted implicit copy assignment operator.
> > > 
> > > ```
> > > /// Sema - This implements semantic analysis and AST building for C.
> > > class Sema final {
> > >   Sema(const Sema &) = delete;
> > >   void operator=(const Sema &) = delete;
> > > ```
> > > It seems like support for assignment is not desired, We probably need deleted copy/move assignment operator.
> > > 
> > These are also implicitly deleted. Some code styles want this explicitly spelled out, but I don't think ours does.
> > I tried to define move assignment operator in  clang/lib/Sema/Sema.cpp but it failed because class Sema has deleted implicit copy assignment operator.
> 
> It is still permissible to define a move assignment operator if the implicit copy assignment operator is deleted. See https://godbolt.org/z/sGaWd9M44.
> 
> I think it is fine to disable support for assignment for this class pending use cases. But, since a move constructor is explicitly defined, we should also be explicit above move assignment. I added a suggested edit. Without that change, I think Coverity will continue to complain.
I see! Thanks @tahonermann for the explanation


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  https://reviews.llvm.org/D150411/new/

https://reviews.llvm.org/D150411