Fix an aliasing bug which was finally detected by gcc-4.2. fdlibm has

hundreds of similar aliasing bugs, but all except this one seem to have
been fixed by Cygnus and/or NetBSD before the modified version of fdlibm
was imported into FreeBSD in 1994.

PR:		standards/113147
Submitted by:	Steve Kargl <sgk@troutmask.apl.washington.edu>

lib/msun/src/s_frexpf.c

@@ -39,6 +39,6 @@ frexpf(float x, int *eptr)
 	}
 	*eptr += (ix>>23)-126;
 	hx = (hx&0x807fffff)|0x3f000000;
-	*(int*)&x = hx;
+	SET_FLOAT_WORD(x,hx);
 	return x;
 }