Re: macro FIXNUM_OVERFLOW_P in lisp.h is valid ?

[Andreas Schwab <schwab@linux-m68k.org>]

Toru TSUNEYOSHI <t_tuneyosi@hotmail.com> writes:

> I read the code of function `string-to-number', and traced functions or
> macros recursively.
>
>   traces of string-to-number:
>
>     data.c: Fstring_to_number
>       lisp.h: make_fixnum_or_float
>         lisp.h: FIXNUM_OVERFLOW_P
>
>   citation of FIXNUM_OVERFLOW_P (in Emacs 23.1):
>
>     /* Value is non-zero if C integer I doesn't fit into a Lisp fixnum.  */
>
>     #define FIXNUM_OVERFLOW_P(i) \
>       ((EMACS_INT)(i) > MOST_POSITIVE_FIXNUM \
>        || (EMACS_INT) (i) < MOST_NEGATIVE_FIXNUM)
>
> I think FIXNUM_OVERFLOW_P is problematic.

Thanks for the report.  The right fix is to remove the cast, so that the
compiler will promote the operands to the appropriate common type.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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