Re: Gmp now working, but number.c:147 isinf declared implicitly.

[Hugh Sasse]

On Fri, 19 Jan 2007, Kevin Ryde wrote:

> Hugh Sasse <address@hidden> writes:
> >
> > ./.libs/libguile.so: undefined reference to `isinf'
> >
> > At which point I am now stuck.  After all, configure found isinf.
> 
> You might be able to stick something in to save the conftest.c used.

Possibly.  I'm not familiar enough with autoconf to be confident about
that.  Indeed, I'm a bit stuck as to how to get into understanding that
whole area.  There used to be just autoconf, now there's automake, autotools
and I'm really unsure where to start afresh to learn this, despite
googling, blundering around gnu.org in search of something, etc....

> Or maybe it's no more than
> 
>       #include <math.h>
>       int main () { return (isinf(0.0) != 0); }

bash-2.05$ cat isinf.c
#include <stdio.h>
#include <math.h>
int main(void);
int main (void) {
  printf ("isinf(0.0) gives %d\n",isinf(0.0));
  printf ("(isinf(0.0) != 0) gives %d\n",(isinf(0.0) != 0));
  return (0);
}

bash-2.05$ gcc -o isinf isinf.c
bash-2.05$ ./isinf
isinf(0.0) gives 0
(isinf(0.0) != 0) gives 0
bash-2.05$

> 
> In any case if you want to advise what should or shouldn't be tested
> or done ...
> 
> > autoreconf -if
> > (with autoconf 2.61)  I get a vastly different configure script
> > with spurious "-n"s sprinkled throughout:
> >
> > bash-2.05$ gdiff -u configure{.orig,} | head -20
> > --- configure.orig      2006-10-07 04:54:24.000000000 +0100
> > +++ configure   2007-01-16 14:41:07.226209000 +0000
> > @@ -1,6 +1,8 @@
> >  #! /bin/sh
> >  # Guess values for system-dependent variables and create Makefiles.
> > -# Generated by GNU Autoconf 2.60a for guile 1.8.1.
> > +# Generated by GNU Autoconf 2.61 for -n guile
> > + -n 1.8.1
> > +.
> 
> Ahh, thanks.  "echo -n" used in configure.in is not portable :(.  In

No. I've seen all sorts of tests in config files to figure this out.
I think it is even mentioned in Perls (non-autoconf) configure dialogue.

> the AC_INIT you should be able to replace the m4_esyscmd with some
> hard coded numbers.  I'll try to do something that strips the newline
> using m4.

I'll see if it makes any sense to me, but I expect you'll get there first.
> 

        Hugh