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From: Steve Kargl <sgk@troutmask.apl.washington.edu>
To: FX Coudert <fxcoudert@gmail.com>
Cc: Elias Toivanen <elias.a.toivanen@gmail.com>, fortran@gcc.gnu.org
Subject: Re: Request to improve docs: Fortran integer ranges vs. machine representation
Date: Fri, 26 Jan 2024 13:41:59 -0800	[thread overview]
Message-ID: <ZbQnJ5tvCszUOVeW@troutmask.apl.washington.edu> (raw)
In-Reply-To: <7462D05F-F9F6-4F29-8FA7-98C9C1760538@gmail.com>

On Fri, Jan 26, 2024 at 09:23:56PM +0100, FX Coudert wrote:
> 
> This is, for example, legal code (and handled by gfortran as expected):
> 
>   use iso_fortran_env
>   implicit none
>   integer(int8) :: j
>   data j /-128_int8/
>   print *, j
>   end
> 

Interesting example.

% gfcx -o z a.f90 &&  ./z
 -128
% gfcx -o z -pedantic a.f90 && ./z
a.f90:5:20:

    5 |   data j /-128_int8/
      |                    1
Error: Integer too big for its kind at (1). This check can be disabled with the option ‘-fno-range-check’
% gfcx -o z -pedantic -fno-range-check a.f90 && ./z
a.f90:5:20:

    5 |   data j /-128_int8/
      |                    1
Error: Integer too big for its kind at (1). This check can be disabled with the option ‘-fno-range-check’

:-)

-- 
Steve

  reply	other threads:[~2024-01-26 21:42 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-01-26 13:44 Elias Toivanen
2024-01-26 16:50 ` Steve Kargl
2024-01-26 20:23   ` FX Coudert
2024-01-26 21:41     ` Steve Kargl [this message]
2024-01-26 22:38       ` FX Coudert
2024-01-27  2:19         ` Steve Kargl
2024-01-28 10:18         ` Elias Toivanen

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