Re: [PATCH] Add cast to unsigned char to strverscmp

On Nov  7 13:58, Joel Sherrill wrote:
> On Thu, Nov 7, 2024 at 1:06 PM <[email protected]> wrote:
> 
> > On 2024-11-07 09:53, Jeremy Bettis wrote:
> > > GCC 14.2 with -Werror=sign-compare fails on this code.
> > >
> > > Signed-off-by: Jeremy Bettis <[email protected] <mailto:
> > [email protected]>>
> > > ---
> > >   newlib/libc/string/strverscmp.c | 2 +-
> > >   1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/newlib/libc/string/strverscmp.c
> > b/newlib/libc/string/strverscmp.c
> > > index 55966335f..e86718faa 100644
> > > --- a/newlib/libc/string/strverscmp.c
> > > +++ b/newlib/libc/string/strverscmp.c
> > > @@ -76,7 +76,7 @@ int strverscmp(const char *l0, const char *r0)
> > >    else if (c!='0') z=0;
> > >    }
> > >
> > > - if (l[dp]<'1' + 9U && r[dp]<'1' + 9U) {

I'm puzzled.  This doesn't look like newlib code.  Newlib's code looks
like this:

        if (l[dp]-'1'<9U && r[dp]-'1'<9U) {

See https://sourceware.org/git/?p=newlib-cygwin.git;a=blob;f=newlib/libc/string/strverscmp.c;hb=HEAD#l79

Given that l and r are unsigned char anyway, the entire expression
is unsigned, so there shouldn't be a sign-compare error in newlib's
version.


Corinna