Re: [Swarm-Support] Followup: found work-around for missing~/swarmarchiver.scm too

[Marcus G. Daniels]

Bill Northcott wrote:
> On 16/08/2006, at 4:42 AM, Paul Johnson wrote:
> > Yesterday I was bug shooting a problem in and older FC4 and found 
> > that gcc treats 50 differently than 50.0 when used as a (double) 
> > parameter in a draw from a normal distribution, and the value 50 was 
> > converted to 0.  It does not do that anymore in FC5.
>
> C is a strongly typed language.  You can't just feed an integer 
> constant (50) to a function that expects a double and have any 
> guarantee about what will happen.  If you need a floating point 
> argument, you have to use a floating point constant (50.0) or cast the 
> integer.  I would expect that recent gcc compilers will kick you about 
> this sort of thing, unless of course you have turned the warnings off 
> or just ignored them.
Let's consult ISSO/IEC 9899  
http://www.open-std.org/JTC1/SC22/WG14/www/docs/n1124.pdf
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6.3.1.4 Real floating and integer

1  When a finite value of real floating type is converted to an integer 
type other than _Bool, the fractional part is discarded (i.e. the value 
is truncated toward zero).  If the value of the integral part cannot be 
represented by the integer type, the behavior is undefined. [50]

2  When a value of integer type is converted to a real floating type, if 
the value being converted can be represented exactly in the new type, it 
is unchanged.  If the value being converted is in the range of values 
that can be represented but cannot be represented exactly, the result is 
either the nearest higher or nearest lower representable value, chosen 
in an implementation-defined manner.  If the value being converted is 
outside the range of values that can be represented, the behavior is 
undefined.

[50]  The remainder operation performed when a value of integer type is 
converted to unsigned type need not be performed when a value of real 
floating type is converted to unsigned type.  Thus, the range of 
portable real floating values is (-1 Utype_MAX+1).
--

One way a problem could occur is if a prototype was missing.  That is, 
if the compiler didn't have a declaration for the method.   Or perhaps 
it is a bug in the compiler.