Re: GDB/libiberty support for IBM long double

[Luis Machado <luisgpm@linux.vnet.ibm.com>]

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Hi,

> I wonder if we really need to use floatformat_to_double instead of
> floatformat_to_doublest for the split_half cases.  It seems like that
> relies unnecessarily on the host double format.  Do things work better
> if you use floatformat_to_doublest and DOUBLEST variables, instead
> of floatformat_to_double (likewise floatformat_from_doublest)?

The attached patch replaces the use of floatformat_to_double with
floatformat_to_doublest, fixing the problem.

There are other uses of floatformat_to_double in the function, by i'm
not sure if we should just replace every call of that function with the
"doublest" version (likewise with the floatformat_from_double ->
floatformat_from_doublest replacement).

Regards,
-- 
Luis Machado
Software Engineer 
IBM Linux Technology Center

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2008-01-02  Luis Machado  <luisgpm@br.ibm.com>

        * doublest.c (convert_floatformat_to_doublest): Call 
	floatformat_to_doublest instead of floatformat_to_double and use
	DOUBLEST variables.

Index: gdb/doublest.c
===================================================================
--- gdb.orig/doublest.c	2008-01-02 07:52:14.000000000 -0800
+++ gdb/doublest.c	2008-01-02 07:53:06.000000000 -0800
@@ -202,19 +202,19 @@
 
   if (fmt->split_half)
     {
-      double dtop, dbot;
-      floatformat_to_double (fmt->split_half, ufrom, &dtop);
+      DOUBLEST dtop, dbot;
+      floatformat_to_doublest (fmt->split_half, ufrom, &dtop);
       /* Preserve the sign of 0, which is the sign of the top
 	 half.  */
       if (dtop == 0.0)
 	{
-	  *to = (DOUBLEST) dtop;
+	  *to = dtop;
 	  return;
 	}
-      floatformat_to_double (fmt->split_half,
+      floatformat_to_doublest (fmt->split_half,
 			     ufrom + fmt->totalsize / FLOATFORMAT_CHAR_BIT / 2,
 			     &dbot);
-      *to = (DOUBLEST) dtop + (DOUBLEST) dbot;
+      *to = dtop + dbot;
       return;
     }