Re: format is locale aware

[Eric Blake]

On Tue, Jun 08, 2021 at 06:16:05PM +0200, Bruno Haible wrote:
> Hi Eric,
> 
> > However, as previous versions of m4 were NOT locale-aware, enabling
> > locale support on what was supposed to be a minor release feels
> > awkward
> 
> Yes; it can break some existing scripts that invoke m4.
> 
> > > If no, the fix would be in main.c: Add a
> > >   setlocale (LC_NUMERIC, "C");
> > > after setlocale (LC_ALL, "").
> > 
> > Or to use gnulib c-strtod and c-vasnprintf modules.
> 
> Well, c-strtod.c spends some time switching the locale. If the program
> does not contain any other uses of the LC_NUMERIC category of the locale
> (and this will also remain true in future versions of m4), it is more
> efficient to switch the LC_NUMERIC category to "C" once and for all.

I'm finally revisiting this thread, and decided to go with your
approach of forcing LC_NUMERIC instead of importing additional gnulib
modules, at least for the 1.4.x branch.

> 
> c-vasnprintf, OTOH, is just as efficient as vasnprintf.
> 
> Bruno
> 

-- 
Eric Blake, Principal Software Engineer
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