Re: port-sparc/44389

[Mateusz Loskot <mateusz%loskot.net@localhost>]

On 18/01/11 13:35, Martin Husemann wrote:
> The following reply was made to PR port-sparc/44389; it has been noted by GNATS.
>
> From: Martin Husemann<martin%duskware.de@localhost>
> To: gnats-bugs%NetBSD.org@localhost
> Cc:
> Subject: Re: port-sparc/44389
> Date: Tue, 18 Jan 2011 14:30:09 +0100
>
>   Ok - last try - check the output of this one.
>
>   Martin
>
>   #include<stdio.h>
>   #include<stdlib.h>
>   #include<math.h>
>   #include<errno.h>
>
>   int is_number(const char *s)
>   {
>         double r;
>         char *ep;
>         errno = 0;
>         r = strtod(s,&ep);
>         if (ep == s || r == HUGE_VAL || errno == ERANGE)
>                 return 0;
>         while (*ep == ' ' || *ep == '\t' || *ep == '\n')
>                 ep++;
>         if (*ep == '\0')
>                 return 1;
>         else
>                 return 0;
>   }
>
>   int main(int argc, char **argv)
>   {
>         double v;
>
>         if (is_number("NaN")) {
>                 printf("is a number\n");
>                 v = atof("NaN");
>         } else {
>                 printf("not a number\n");
>                 v = 0.0;
>         }
>         printf("%.4f\n", v);
>
>         return 0;
>   }


This one receive SIGFPE:

$ gcc ./nan_test_2.c
$ ./a.out
[1]   Floating point exception (core dumped) ./a.out

Specifically, it's caused by r == HUGE_VAL condition in
if (ep == s || r == HUGE_VAL || errno == ERANGE)

Though, not sure about conclusion.

--
Mateusz Loskot, http://mateusz.loskot.net
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Member of ACCU, http://accu.org