Re: [PATCH] [v2] scripts/unifdef: avoid constexpr keyword

[Masahiro Yamada]

On Mon, Apr 8, 2024 at 4:18 PM Arnd Bergmann <arnd@xxxxxxxxxx> wrote:
>
> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> Starting with c23, 'constexpr' is a keyword in C like in C++ and cannot
> be used as an identifier:
>
> scripts/unifdef.c:206:25: error: 'constexpr' can only be used in variable declarations
>   206 | static bool             constexpr;              /* constant #if expression */
>       |                         ^
> scripts/unifdef.c:880:13: error: expected identifier or '('
>   880 |                 constexpr = false;
>       |                           ^
>
> Rename this instance to allow changing to C23 at some point in the future.
>
> Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
> Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
> Cc: Nicolas Schier <nicolas@xxxxxxxxx>
> Cc: linux-kbuild@xxxxxxxxxxxxxxx
> Reviewed-By: Tony Finch <dot@xxxxxxxx>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> ---
>  v2: include fixup from Tony


Applied to linux-kbuild. Thanks.


> ---
>  scripts/unifdef.c | 12 ++++++------
>  1 file changed, 6 insertions(+), 6 deletions(-)
>
> diff --git a/scripts/unifdef.c b/scripts/unifdef.c
> index db00e3e30a59..ff15efd6e7d7 100644
> --- a/scripts/unifdef.c
> +++ b/scripts/unifdef.c
> @@ -203,7 +203,7 @@ static int              depth;                      /* current #if nesting */
>  static int              delcount;              /* count of deleted lines */
>  static unsigned         blankcount;            /* count of blank lines */
>  static unsigned         blankmax;              /* maximum recent blankcount */
> -static bool             constexpr;             /* constant #if expression */
> +static bool             constexpression;       /* constant #if expression */
>  static bool             zerosyms = true;       /* to format symdepth output */
>  static bool             firstsym;              /* ditto */
>
> @@ -819,7 +819,7 @@ static const struct ops {
>  /*
>   * Function for evaluating the innermost parts of expressions,
>   * viz. !expr (expr) number defined(symbol) symbol
> - * We reset the constexpr flag in the last two cases.
> + * We reset the constexpression flag in the last two cases.
>   */
>  static Linetype
>  eval_unary(const struct ops *ops, int *valp, const char **cpp)
> @@ -877,7 +877,7 @@ eval_unary(const struct ops *ops, int *valp, const char **cpp)
>                 cp = skipcomment(cp);
>                 if (defparen && *cp++ != ')')
>                         return (LT_ERROR);
> -               constexpr = false;
> +               constexpression = false;
>         } else if (!endsym(*cp)) {
>                 debug("eval%d symbol", ops - eval_ops);
>                 sym = findsym(cp);
> @@ -895,7 +895,7 @@ eval_unary(const struct ops *ops, int *valp, const char **cpp)
>                         lt = *valp ? LT_TRUE : LT_FALSE;
>                         cp = skipargs(cp);
>                 }
> -               constexpr = false;
> +               constexpression = false;
>         } else {
>                 debug("eval%d bad expr", ops - eval_ops);
>                 return (LT_ERROR);
> @@ -955,10 +955,10 @@ ifeval(const char **cpp)
>         int val = 0;
>
>         debug("eval %s", *cpp);
> -       constexpr = killconsts ? false : true;
> +       constexpression = killconsts ? false : true;
>         ret = eval_table(eval_ops, &val, cpp);
>         debug("eval = %d", val);
> -       return (constexpr ? LT_IF : ret == LT_ERROR ? LT_IF : ret);
> +       return (constexpression ? LT_IF : ret == LT_ERROR ? LT_IF : ret);
>  }
>
>  /*
> --
> 2.39.2
>


-- 
Best Regards
Masahiro Yamada