Paul Eggert wrote: > IBM mainframes use radix 16. This is not likely to change so long as > there are IBM mainframes (which will be quite some time). Modern IBM > mainframes support radix 2 as an option, but I suspect radix 16 is > still the normal default
Oh well. I'm adding a comment about it. May the problem be handled when it actually occurs. (Are such mainframes porting targets for GNU software? Do they lack the C99 printf 'a' and 'A' conversion?) > Radix-10 floating point is making a bit of a comeback, by the way. > Usually, though, it's not via redefining 'double'. See, for example, > <http://www2.hursley.ibm.com/decimal/>. Yes. Decimal arithmetic is a basic datatype for financial applications. Now also gcc comes with a libdecnumber. Bruno --- lib/printf-frexp.c 25 Feb 2007 14:20:46 -0000 1.1 +++ lib/printf-frexp.c 25 Feb 2007 18:08:24 -0000 1.3 @@ -28,10 +28,10 @@ # include <float.h> # include <math.h> -# include "verify.h" -/* This file assumes FLT_RADIX is 2. */ -verify (FLT_RADIX == 2); +/* This file assumes FLT_RADIX = 2. If FLT_RADIX is a power of 2 greater + than 2, or not even a power of 2, some rounding errors can occur, so that + then the returned mantissa is only guaranteed to be <= 2.0, not < 2.0. */ # ifdef USE_LONG_DOUBLE # define FUNC printf_frexpl --- modules/printf-frexp 25 Feb 2007 14:20:46 -0000 1.1 +++ modules/printf-frexp 25 Feb 2007 17:41:48 -0000 @@ -8,7 +8,6 @@ m4/printf-frexp.m4 Depends-on: -verify configure.ac: gl_FUNC_PRINTF_FREXP --- modules/printf-frexpl 25 Feb 2007 14:28:50 -0000 1.1 +++ modules/printf-frexpl 25 Feb 2007 17:41:48 -0000 @@ -10,7 +10,6 @@ m4/longdouble.m4 Depends-on: -verify configure.ac: gl_FUNC_PRINTF_FREXPL
