re PR libfortran/86070 (gfortran.dg/fmt_zero_digits.f90 segmentation fault starting with r261077)

2018-06-09  Jerry DeLisle  <jvdelisle@gcc.gnu.org>

	PR libgfortran/86070
	* io/write_float.def (build_float_string): Initialize *len.

From-SVN: r261382

libgfortran/ChangeLog

+2018-06-09  Jerry DeLisle  <jvdelisle@gcc.gnu.org>
+
+	PR libgfortran/86070
+	* io/write_float.def (build_float_string): Initialize *len.
+
 2018-06-01  Steven G. Kargl  <kargl@gcc.gnu.org>
 
 	PR fortran/85816

libgfortran/io/write_float.def

@@ -135,6 +135,7 @@ build_float_string (st_parameter_dt *dtp, const fnode *f, char *buffer,
   w = f->u.real.w;
   d = f->u.real.d;
   p = dtp->u.p.scale_factor;
+  *len = 0;
 
   rchar = '5';