Re: Problems VPATH, pow

[Jeff Johnston <jjohnstn at redhat dot com>]

Davies, Daniel wrote:
> Sorry for the subject-less message - I hit the send button too soon. 
>
> -----Original Message-----
> From: Davies, Daniel 
> Sent: Monday, August 29, 2005 1:57 PM
> To: 'newlib@sources.redhat.com'
> Cc: Davies, Daniel
> Subject: 
>
> First, let me thank everyone involved with newlib, it has certainly made
> my life easier!
>  
> I'm cross compiling newlib 1.13.0 for powerpc-unknown-eabialtivec on
> i386-pc-solaris2.10.  I'm using version 3.80 of gnu make and gcc 4.0.1.
>  
> Two nits:
>  
> 1. This is probably a solairs-ism.  The VPATH declaration in
> newlib-1.13.0/libgloss/rs6000/Makefile.in is
>  
> VPATH = @srcdir@ @srcdir@/..
>  
> This does not work in Solairs.
>  
> VPATH = @srcdir@:@srcdir@/..
>  
> (replaced space with colon) works.
>  

I have changed this over to use colon as gnu make accepts either space 
or colon.

> 2. pow(0, y) = 1 for all y > 0, e.g. 0^2 = 1.  It looks like pow doesn't
> check for this case, takes the log of 0 (which is undefined), gets a
> number very close to 0 instead of an approximation to minus infinity,
> later takes exp of this number and gets 1.

Can you provide a test that demonstrates your problem?  I have a simple 
test which when run on mn10300 and linux, works as expected (result of
pow (0,2) is 0).

#include <stdio.h>
#include <math.h>

int main (void)
{
  printf ("pow (1,2) is %g\n", pow (1, 2));
  printf ("pow (0,2) is %g\n", pow (0, 2));
  printf ("pow (2,2) is %g\n", pow (2, 2));
  return 0;
}
~
bash-3.00$ ./a.out
pow (1,2) is 1
pow (0,2) is 0
pow (2,2) is 4


> Dan