[9fans] compiler double bug.

[erik quanstrom]

after 5 hrs of tracking a floating point exception in
awk (present in all versions i could find), i isolated
this sequence of events, which does not require ape:

#include <u.h>
#include <libc.h>

void
main(void)
{
        double g = 4215866817.;

        print("%d\n", (int)g);
        print("%d\n", (int)g);
        exits("");
}

; 8c -FVTw x.c && 8l x.8 && 8.out
-2147483648
8.out 26264: suicide: sys: fp: invalid operation fppc=0x105d status=0xc0a1 
pc=0x107a

- erik