4 ms·

and you CAN use static_cast to convert from void; this silently keeps working if you refactor the void into a matching-type pointer later, while raising a com

and you CAN use static_cast to convert from void*; this silently keeps working if you refactor the void* into a matching-type pointer later, while raising a compilation error if you refactor to a different-type pointer.

uecker 4mo ago
Yes, a static_cast would be safe, but then most C++ seems to use a C-style cast because it is less clunky and then is less safe than the corresponding C code. The issue is not that the downcast is unsafe (it is, but once you have a void pointer you already accepted this), but that it becomes even less safe by adding a C-style cast. It is also not clear what is gained by forcing programmers to add a cast. Void pointers should be used sparingly anyway.
- spacechild1 4mo ago
  > but then most C++ seems to use a C-style cast If C++ programmers do not use modern safety features, that's really their fault. C-style pointer casts should be flagged in code review. > but that it becomes even less safe by adding a C-style cast. At least in C++ there is a safer option. If you really want to be on the safe side, you can even to a dynamic_cast (assuming your code base allows RTTI). > It is also not clear what is gained by forcing programmers to add a cast. I think the point is to make it explicit and stand out.
  - account42 4mo ago
    Lack of ergonomics around static_cast is language problem. The "most safe" of the casts should not be this verbose.
    - spacechild1 4mo ago
      I see your point. It would be nice if a C-style cast behaved like a static_cast in C++, but that's not possible because of backwards compatibility. At least with GCC/Clang you can disable C-style casts altogether with '-Werror=old-style-cast'. (Maybe there is a similar option for MSVC.)
      - account42 4mo ago
        Yes, this is something that would need a new language edition to properly fix. Compiler vendors could split -Wold-style-cast into separate warnings for static_cast and other usage though so that you can only ban one of them.

and you CAN use static_cast to convert from void*; this silently keeps working if you refactor the void* into a matching-type pointer later, while raising a com

uecker 4mo ago

Yes, a static_cast would be safe, but then most C++ seems to use a C-style cast because it is less clunky and then is less safe than the corresponding C code. The issue is not that the downcast is unsafe (it is, but once you have a void pointer you already accepted this), but that it becomes even less safe by adding a C-style cast. It is also not clear what is gained by forcing programmers to add a cast. Void pointers should be used sparingly anyway.

spacechild1 4mo ago
> but then most C++ seems to use a C-style cast If C++ programmers do not use modern safety features, that's really their fault. C-style pointer casts should be flagged in code review. > but that it becomes even less safe by adding a C-style cast. At least in C++ there is a safer option. If you really want to be on the safe side, you can even to a dynamic_cast (assuming your code base allows RTTI). > It is also not clear what is gained by forcing programmers to add a cast. I think the point is to make it explicit and stand out.
- account42 4mo ago
  Lack of ergonomics around static_cast is language problem. The "most safe" of the casts should not be this verbose.
  - spacechild1 4mo ago
    I see your point. It would be nice if a C-style cast behaved like a static_cast in C++, but that's not possible because of backwards compatibility. At least with GCC/Clang you can disable C-style casts altogether with '-Werror=old-style-cast'. (Maybe there is a similar option for MSVC.)
    - account42 4mo ago
      Yes, this is something that would need a new language edition to properly fix. Compiler vendors could split -Wold-style-cast into separate warnings for static_cast and other usage though so that you can only ban one of them.