Re: `SCM_MAKE_CHAR ()' signedness issue

["carlo\.bramix" <carlo.bramix@libero.it>]

Hello,
unfortunately that code still fails into libguile/print.c
Infact, a signed char just arrives to 127 and the " < 128" causes:

../../guile-git/libguile/print.c:1101: warning: comparison is always true due to limited range of data type
../../guile-git/libguile/print.c:1108: warning: comparison is always true due to limited range of data type

But in this manner it seems ok:

#define SCM_MAKE_CHAR(x)                                               \
  (((scm_t_int32) (x) + 128) < 128                                     \
   ? SCM_MAKE_ITAG8 ((scm_t_bits) (unsigned char) (x), scm_tc8_char)   \
   : SCM_MAKE_ITAG8 ((scm_t_bits) (x), scm_tc8_char))

Sincerely,

Carlo Bramini.

---------- Initial Header -----------

From      : guile-devel-bounces+carlo.bramix=libero.it@gnu.org
To          : "Ludovic Courtès" ludo@gnu.org, guile-devel@gnu.org
Cc          :
Date      : Tue, 18 Aug 2009 10:32:29 -0700 (PDT)
Subject : Re: `SCM_MAKE_CHAR ()' signedness issue

> > From: Ludovic Courtès <ludo@gnu.org>
> > To: guile-devel@gnu.org
> > Sent: Monday, August 17, 2009 8:33:03 AM
> > Subject: Re: `SCM_MAKE_CHAR ()' signedness issue
> >
> > I'm fairly confident that for such a small piece of code inlining is
> > always a good idea.
>
> OK.  If the comparison is modified to become
>
> 35 #define SCM_MAKE_CHAR(x)                                               \
> 36   (((x) < 128)                                               \
> 37    ? SCM_MAKE_ITAG8 ((scm_t_bits) (unsigned char) (x), scm_tc8_char)   \
> 38    : SCM_MAKE_ITAG8 ((scm_t_bits) (x), scm_tc8_char))
>
> Then hopefully that will solve all the build problems.
>
> > Thanks,
> > Ludo'.
>
> -Mike
>
>
>
>