Set flag_pic to flag_pie for PIE in LTO

Since PIE implies PIC, we should set flag_pic to flag_pie for PIE in
LTO.

	PR lto/70258
	* lto-lang.c (lto_post_options): Set flag_pic to flag_pie for
	PIE.

From-SVN: r234284

gcc/lto/ChangeLog

+2016-03-17  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR lto/70258
+	* lto-lang.c (lto_post_options): Set flag_pic to flag_pie for
+	PIE.
+
 2016-03-08  Jakub Jelinek  <jakub@redhat.com>
 
 	* lto-symtab.h (lto_symtab_prevail_decl): Fix spelling

gcc/lto/lto-lang.c

@@ -836,7 +836,7 @@ lto_post_options (const char **pfilename ATTRIBUTE_UNUSED)
       /* If -fPIC or -fPIE was used at compile time, be sure that
          flag_pie is 2.  */
       flag_pie = MAX (flag_pie, flag_pic);
-      flag_pic = 0;
+      flag_pic = flag_pie;
       break;
 
     case LTO_LINKER_OUTPUT_EXEC: /* Normal executable */