From: Jonathan Wakely <jwakely.gcc@gmail.com>
To: Jay K <jayk123@hotmail.com>
Cc: gcc <gcc@gcc.gnu.org>
Subject: Re: extern const initialized warns in C
Date: Mon, 22 Jan 2018 15:19:00 -0000 [thread overview]
Message-ID: <CAH6eHdQ+42VO14YtZrYpzC4rz+0_C37L7RfsEXf1gBALqRGCyg@mail.gmail.com> (raw)
In-Reply-To: <MWHPR18MB121457D8901E94B1F0F339D6E6ED0@MWHPR18MB1214.namprd18.prod.outlook.com>
On 21 January 2018 at 07:12, Jay K wrote:
> extern const int foo = 123;
>
>
>
> Why does this warn?
> This is a valid portable form, with the same meaning
> across all compilers, and, importantly, portably
> to C and C++.
>
> I explicitly do not want to say:
>
> const int foo = 123
>
> because I want the code to be valid and have the same meaning
> in C and C++ (modulo name mangling).
>
> I end up with:
>
> // Workaround gcc warning.
> #ifdef __cplusplus
> #define EXTERN_CONST extern const
> #else
> #define EXTERN_CONST const
> #endif
>
>
> EXTERN_CONST int foo = 123;
>
> and having to explain it to people.
Why not simply:
extern const int foo;
const int foo = 123;
without the ugly macro?
Or, according to taste:
// Without an extern declaration, file-scope const variables are static:
extern const int foo;
const int foo = 123;
Or:
#ifdef __cplusplus
// Without an extern declaration, file-scope const variables are static:
extern const int foo;
#endif
const int foo = 123;
But your macro version is just ugly. And instead of complaining that
you have to explain it to people, why not explain it with a comment in
the code? That's what comments are for.
prev parent reply other threads:[~2018-01-22 15:19 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <MWHPR18MB121493D9F2292547E0AF6C3AE6ED0@MWHPR18MB1214.namprd18.prod.outlook.com>
2018-01-21 7:12 ` Jay K
2018-01-21 12:08 ` Georg-Johann Lay
2018-01-22 9:44 ` Franz Sirl
2018-01-22 15:20 ` Jonathan Wakely
2018-01-25 12:27 ` Georg-Johann Lay
2018-01-25 12:29 ` Jonathan Wakely
2018-01-25 12:30 ` Jonathan Wakely
2018-01-22 8:32 ` David Brown
2018-01-22 9:32 ` Jay K
2018-01-22 9:39 ` Jay K
2018-01-22 10:14 ` David Brown
2018-01-22 10:25 ` Jay K
2018-01-22 9:54 ` David Brown
[not found] ` <MWHPR18MB12145B5B3E0B093993C2D214E6EC0@MWHPR18MB1214.namprd18.prod.outlook.com>
2018-01-22 10:42 ` David Brown
2018-01-22 11:27 ` Jay K
2018-01-22 13:02 ` David Brown
2018-01-22 16:22 ` Vincent Lefevre
2018-01-22 15:19 ` Jonathan Wakely [this message]
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