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In-Reply-To: <aTfPRxNYuYWVLI+3@ip-10-97-1-34.eu-west-3.compute.internal>
From: Thomas Munro <thomas.munro@gmail.com>
Date: Tue, 9 Dec 2025 22:10:39 +1300
Message-ID: 
 <CA+hUKGLYn6jxMSptjzMqBZ7ZYKQ2cewiKjg31zUR+ZR3E+mu+Q@mail.gmail.com>
Subject: Re: Safer hash table initialization macro
To: Bertrand Drouvot <bertranddrouvot.pg@gmail.com>
Cc: Jelte Fennema-Nio <postgres@jeltef.nl>, pgsql-hackers@lists.postgresql.org
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On Tue, Dec 9, 2025 at 8:27=E2=80=AFPM Bertrand Drouvot
<bertranddrouvot.pg@gmail.com> wrote:
> On Mon, Dec 08, 2025 at 11:53:02AM +0100, Jelte Fennema-Nio wrote:
> > On Sat Dec 6, 2025 at 1:56 AM CET, Thomas Munro wrote:
> +#if defined(__cplusplus)
> +#define pg_expr_has_type_p(expr, type) (std::is_same<decltype(expr), typ=
e>::value)
> +#else
> +#define pg_expr_has_type_p(expr, type) \
> +       _Generic((expr), type: 1, default: 0)
> +#endif
>
> What about relying on the existing __builtin_types_compatible_p() instead=
 of
> _Generic() here?

If we used standard C/C++ it'd work on MSVC too.