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Re: Allow [[deprecated]] on call site to disable deprecated warning

From: Ville Voutilainen <ville.voutilainen_at_[hidden]>
Date: Thu, 28 Jan 2021 13:34:19 +0200
On Thu, 28 Jan 2021 at 13:06, Dominic Fandrey via Std-Proposals
<std-proposals_at_[hidden]> wrote:
>
> I recently ran into this issue:
>
> 1. Marked a set of legacy methods [[deprecated]]
> 2. Unit tests no longer compile (we run -Wall -Werror of course)
>
> Of course I don't want to get rid of the unit tests before I get rid of the
> functions. So I was faced with two choices:
>
> 1. Create #ifdef #pragma soup for all 3 compilers that we use
> 2. Remove [[deprecated]]
>
> The #ifdef #pragma soup needs to be updated every time a compiler is added,
> and it bloats the code and makes unit tests more difficult to read. So I
> went for option 2. As long as I cannot ignore [[deprecated]] in a portable
> manner I cannot use it.
>
> So my suggestion is:
>
> ```
> [[deprecated("use: std::optional<std::size_t> size()")]]int size(std::size_t & size);
>
>
> bool test_size() {
> std::size_t s{0};
> return 0 == [[deprecated]]size(s) && s != 0;
> }

Create your own MY_DEPRECATED macro, make it expand to actual
deprecation normally, but not in unit tests,
compile the unit tests with -DMY_SOMETHING that disables deprecations.
Or just add a #define into
your unit tests.

I have fair amounts of sympathy for your situation, but adding more
language bells&whistles to control what
these attributes are doing is getting out of hand, imho. I deal with
half-a-dozen compilers and every new
warning breaks something somewhere, as does every deprecation.

Received on 2021-01-28 05:34:33