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

From: Avi Kivity <avi_at_[hidden]>
Date: Sun, 7 Feb 2021 12:22:11 +0200
On 28/01/2021 13.34, Ville Voutilainen via Std-Proposals wrote:
> 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.


Doesn't that break with modules?


We should not be suggesting solutions that involve the preprocessor in 2021.

Received on 2021-02-07 04:22:16