Re: [PATCH v6 2/4] Compiler Attributes: Add __overloadable for Clang

From: Nick Desaulniers
Date: Thu Feb 03 2022 - 17:12:05 EST


On Thu, Feb 3, 2022 at 1:04 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>
> On Thu, Feb 03, 2022 at 12:26:15PM -0800, Nick Desaulniers wrote:
> > On Thu, Feb 3, 2022 at 9:33 AM Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> > >
> > > must be marked as being overloadable (i.e. different prototypes).
> > > This allows the __pass_object_size versions to take precedence.
> >
> > Is this because of the `const` additions to the function signatures?
>
> That might be an issue, but the *real* issue is the implicit mutation of
> the function into an inline with _additional_ arguments. i.e.
>
> char *strcpy(char * POS p, const char * POS q)
>
> is really
>
> char *strcpy(char * const p, const char * const q, size_t __size_of_p, size_t __size_of_q)
>
> (i.e. what I was doing with macros, but all internally and still an
> extern inline)

What do you mean "is really"? 4/4 doesn't change the number of
parameters in strcpy explicitly in the definition AFAICT.
--
Thanks,
~Nick Desaulniers