lkml.org 
[lkml]   [2020]   [Apr]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH 1/1] lib/vsprintf: Add support for printing V4L2 and DRM fourccs
From
Date
On Fri, 2020-04-03 at 09:37 +0300, Jani Nikula wrote:
> On Thu, 02 Apr 2020, Joe Perches <joe@perches.com> wrote:
> > On Thu, 2020-04-02 at 11:34 +0300, Jani Nikula wrote:
> > > Or could we conceive of a way to make this locally extensible yet safe,
> > > letting callers use something like %{foo}, as well as providing a
> > > locally relevant function to do the conversion?
> >
> > No. printf validation would be broken.
>
> I tossed the idea on a whim, and thinking further I could probably come
> up with a number of challenges, but care to elaborate on what you see as
> the problem in validation?

I understand you to want to add something like

%<m> where m is a non-standard format specifier

so using using gcc's extension of

__attribute__((__format__(printf, string_index, first_to_check))

could not validate the argument type against use of the %<m>
in the format string.

printk("%a\n", a);

Compiler bleats.

\
 
 \ /
  Last update: 2020-04-03 15:13    [W:0.036 / U:2.472 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site