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Re: exotic floating point formats test


Zack Weinberg wrote:
> 
> I'd appreciate knowing what this program prints on a VAX (or an Alpha
> asked to use VAX floating point), an IBM mainframe target, and a C4x
> processor.  For reference:
> 
> i686-pc-linux-gnu $ ./a.out
> 3.25098346789696250880e+01      46454443 42414040       FEDC BA@@
> sparc-sun-solaris2.7 $ ./a.out
> 3.25098346789696250880e+01      40404142 43444546       @@AB CDEF
> 
> [that's little- and big-endian IEEE, respectively]

After changing the format string to be in one quote,
and changing the format from %.2x to %02.2x, I got
the following results (note that there are two
floating point formats for C on the VAX)

VAX/VMS 5.5 D-FLOAT format
$ cc untitled.c
$ link untitled, sys$library:vaxcrtl/lib
$ run untitled
3.25098346789696250880e+01      0243120a 221a302a       .C.. ".0*
%NONAME-W-NOMSG, Message number 00000000

VAX/VMS 5.5 G-FLOAT format
$ cc untitled.c/g_float
$ link untitled, sys$library:vaxcrtl/lib
$ run untitled
3.25098346789696250880e+01      60404241 44434645       `@BA DCFE
%NONAME-W-NOMSG, Message number 00000000

> If you want to be clever and come up with floating point numbers that
> generate recognizable, distinct, strings in those formats, that'd be
> even niftier.
> 
> Also, does anyone know why c4x.h requests an exotic target float
> format, but xm-c4x.h leaves us in IEEE on the host?

-- 
If they're not putting secret messages to me in their music, then why
do they keep putting my picture on the other side of the CD's?


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