alexfh added inline comments. ================ Comment at: docs/clang-tidy/checks/misc-user-defined-copy-without-assignment.rst:6 @@ +5,3 @@ + +MSVC 2015 will generate an assignment operator even if the user defines a copy constructor. +This check finds classes with a user-defined (including deleted) ---------------- aaron.ballman wrote: > alexfh wrote: > > Is this problem only relevant to MSVC 2015? Is MSVC's behavior > > standard-compliant in this case? > MSVC's behavior is standards compliant, but is deprecated behavior. > [class.copy]p18: > > "If the class definition does not explicitly declare a copy assignment > operator, one is declared implicitly. If > the class definition declares a move constructor or move assignment operator, > the implicitly declared copy > assignment operator is defined as deleted; otherwise, it is defined as > defaulted (8.4). The latter case is > deprecated if the class has a user-declared copy constructor or a > user-declared destructor." > > Now that I think about it more, I thought @dblaikie or @rsmith made a check > for this once under -Wdeprecated. It looks like Richard did in r183884. Ah, now I start understanding ;)
The check is actually (incompletely) verifying [[ https://en.wikipedia.org/wiki/Rule_of_three_(C%2B%2B_programming) | the rule of 2 ]], and it's not specific to MSVC in any way (and the documentation shouldn't mention MSVC then). It makes sense to: 1. make the check symmetric (a user-defined assignment and an implicit copy-construction; 2. extend the check to verify move operations as well (the rule of 4); 3. and maybe extend it to verify the rule of 3 and the rule of 5 (though detecting non-RAII resource owning may be really hard if even possible). ================ Comment at: docs/clang-tidy/checks/misc-user-defined-copy-without-assignment.rst:23 @@ +22,3 @@ + +The fix is defensive. Incorrect compiler-generated assignement can cause +unexpected behaviour. An explicitly deleted assigneemnt operator will cause a ---------------- The fix will break code that uses the implicit assignment operator. I'm not sure it's a nice thing to do in a check enabled by default. Repository: rL LLVM http://reviews.llvm.org/D16376 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
