Re: coreutils 6.9.92 fail to configure on *bsd

[Bruno Haible]

Elias Pipping wrote:
> On a sidenote... looking at the first couple of lines in the float.h
> that i attached to that last mail:
> 
>   /* This file exists soley to keep Metrowerks' compilers happy.  The version
>      used by GCC can be found in /usr/lib/gcc, although it's
>      not very informative.  */
> 
> It might make sense to attach this file
> 
>   /usr/lib/gcc/i686-apple-darwin9/4.0.1/include/float.h
> 
> as well. So I did.

Thanks. Yes, that file is the one that used by gcc. But it only contains
placeholders that refer to compiler internals, so it is of no use when I
wanted to know the precise values. You already sent me the values produced
by printf statements, that's what I needed.

>   % gcc foo.c 
>   % ./a.out 
>   -16384 0.5

Thanks, that's the testimony that the system frexpl() is working incorrectly.
I apply this workaround to gnulib:

2008-01-15  Bruno Haible  <address@hidden>

        Work around a MacOS X 10.5 bug in frexpl().
        * m4/frexpl.m4 (gl_FUNC_FREXPL_WORKS): Also check denormalized numbers.
        * doc/functions/frexpl.texi: Document the bug.
        Reported by Elias Pipping <address@hidden>.

*** doc/functions/frexpl.texi.orig      2008-01-16 00:20:47.000000000 +0100
--- doc/functions/frexpl.texi   2008-01-16 00:10:15.000000000 +0100
***************
*** 15,20 ****
--- 15,23 ----
  This function does not work on finite numbers on some platforms:
  MacOS X 10.4/PowerPC, AIX 5.1, BeOS.
  @item
+ This function does not work on denormalized numbers on some platforms:
+ MacOS X 10.5/i386.
+ @item
  This function does not work on infinite numbers on some platforms:
  IRIX 6.5, mingw.
  @end itemize
*** m4/frexpl.m4.orig   2008-01-16 00:20:47.000000000 +0100
--- m4/frexpl.m4        2008-01-16 00:20:39.000000000 +0100
***************
*** 1,5 ****
! # frexpl.m4 serial 6
! dnl Copyright (C) 2007 Free Software Foundation, Inc.
  dnl This file is free software; the Free Software Foundation
  dnl gives unlimited permission to copy and/or distribute it,
  dnl with or without modifications, as long as this notice is preserved.
--- 1,5 ----
! # frexpl.m4 serial 7
! dnl Copyright (C) 2007-2008 Free Software Foundation, Inc.
  dnl This file is free software; the Free Software Foundation
  dnl gives unlimited permission to copy and/or distribute it,
  dnl with or without modifications, as long as this notice is preserved.
***************
*** 96,103 ****
  ])
  
  dnl Test whether frexpl() works on finite numbers (this fails on
! dnl MacOS X 10.4/PowerPC, on AIX 5.1, and on BeOS) and also on infinite 
numbers
! dnl (this fails e.g. on IRIX 6.5 and mingw).
  AC_DEFUN([gl_FUNC_FREXPL_WORKS],
  [
    AC_REQUIRE([AC_PROG_CC])
--- 96,104 ----
  ])
  
  dnl Test whether frexpl() works on finite numbers (this fails on
! dnl MacOS X 10.4/PowerPC, on AIX 5.1, and on BeOS), on denormalized numbers
! dnl (this fails on MacOS X 10.5/i386), and also on infinite numbers (this
! dnl fails e.g. on IRIX 6.5 and mingw).
  AC_DEFUN([gl_FUNC_FREXPL_WORKS],
  [
    AC_REQUIRE([AC_PROG_CC])
***************
*** 144,149 ****
--- 145,165 ----
            return 1;
        }
    }
+   /* Test on denormalized numbers.  */
+   {
+     int i;
+     for (i = 1, x = 1.0L; i >= LDBL_MIN_EXP; i--, x *= 0.5L)
+       ;
+     if (x > 0.0L)
+       {
+         int exp;
+         long double y = frexpl (x, &exp);
+         /* On machines with IEEE854 arithmetic: x = 1.68105e-4932,
+            exp = -16382, y = 0.5.  On MacOS X 10.5: exp = -16384, y = 0.5.  */
+         if (exp != LDBL_MIN_EXP - 1)
+           return 1;
+       }
+   }
    /* Test on infinite numbers.  */
    x = 1.0L / 0.0L;
    {