Re: Make copyObject work in C++

On 05.12.25 15:46, Jelte Fennema-Nio wrote:
> Calling copyObject fails in C++ with an error like in most setups:
> 
> error: use of undeclared identifier 'typeof'; did you mean 'typeid'
> 
> This is due to the C compiler supporting used to compile postgres
> supporting typeof, but that function actually not being present in the
> C++ compiler. This fixes that by using decltype instead of typeof when
> including the header in C++.
> 
> Realized because of Thomas' not about how much of our headers should
> work in C++, and remembering I hit this specific problem myself.
> 
> Another approach would be to force the value of HAVE_TYPEOF to 0 if __cplusplus.

In the long run, I would like to change copyObject() to use 
typeof_unqual instead, because that handles qualifiers more correctly. 
(Currently, copyObject() of a const-qualified pointer results in a 
const-qualified pointer, which is nonsensical because the reason you 
made the copy is that you can modify it.)  See attached patch for an 
example.  Does C++ have something that is semantically similar to that?