Date: Fri, 14 Nov 2008 22:02:30 +0100 From: Andreas Tobler <andreast-list@fgznet.ch> To: Peter Grehan <grehan@freebsd.org> Cc: FreeBSD PowerPC ML <freebsd-ppc@freebsd.org> Subject: Re: ppc float.h Message-ID: <491DE766.8040705@fgznet.ch> In-Reply-To: <491C7C47.8080803@fgznet.ch> References: <20081113105926.ELO26264@dommail.onthenet.com.au> <491C7C47.8080803@fgznet.ch>
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Hi Peter, Andreas Tobler wrote: > Peter Grehan wrote: > >>> can somebody explain why we have these defines in >>> sys/powerpc/include/float.h ? >> >> Have a look at >> >> http://svn.freebsd.org/viewvc/base?view=revision&revision=132421 > > Hm, meanwhile OS-X has 128-bit long double... > >> Basically, the ABI was switched from 128 bit long doubles to >> 64. Not exactly SVR4 compliant but then no-one else is. > > And there is no need to go back to 128-bit? No benefit? > What would have to be done? Libc? I know the compiler issue. > Would this break too much? Coming back to myself. Doesn't matter if going to 128-bit long double or not. The LDBL_MIN/MAX/EPSILON definitions in float.h are wrong. If you do a printf ("%Lf\n", LDBL_EPSILON); you run into a compiler warning: warning: format '%Lf' expects type 'long double', but argument 2 has type 'double' So to fix that I propose the appended patch. Thanks, Andreas P.S, making the compiler work with 128-bit long-double is still possible. [wolfram:~] andreast% diff -u float.h~ float.h --- float.h~ 2008-11-14 21:31:00.000000000 +0100 +++ float.h 2008-11-14 21:32:07.000000000 +0100 @@ -72,13 +72,13 @@ #define DBL_MAX_10_EXP 308 #define LDBL_MANT_DIG DBL_MANT_DIG -#define LDBL_EPSILON DBL_EPSILON +#define LDBL_EPSILON 2.2204460492503131e-16L #define LDBL_DIG DBL_DIG #define LDBL_MIN_EXP DBL_MIN_EXP -#define LDBL_MIN DBL_MIN +#define LDBL_MIN 2.2250738585072014e-308L #define LDBL_MIN_10_EXP DBL_MIN_10_EXP #define LDBL_MAX_EXP DBL_MAX_EXP -#define LDBL_MAX DBL_MAX +#define LDBL_MAX 1.7976931348623157e+308L #define LDBL_MAX_10_EXP DBL_MAX_10_EXP #endif /* _MACHINE_FLOAT_H_ */home | help
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