#! perl -slw
use strict; use Config;
use Inline C => Config => BUILD_NOISY => 1, CCFLAGS => $Config{ccflags}." -DDEBUG=1";
use Inline C => <<'END_C',  NAME => 'ICexample', CLEAN_AFTER_BUILD =>0;

static const unsigned __int64 i = 0x7ff0000000000001;

SV*get_snan() {
    SV *nv = newSVnv(0.0);
    *(unsigned __int64*)&( ((XPVNV*) SvANY(nv))->xnv_u.xnv_nv ) = i;
    return nv;
}

END_C

sub doubleToHex { scalar reverse unpack 'h16', pack 'd', $_[0] }

my $snan = get_snan();

printf "%f\n", $snan;

print doubleToHex( $snan );