Do not allow empty argument of -o option (PR driver/31468).

2017-05-15  Martin Liska  <mliska@suse.cz>

	PR driver/31468
	* gcc.c (process_command): Do not allow empty argument of -o option.

From-SVN: r248060

gcc/ChangeLog

+2017-05-15  Martin Liska  <mliska@suse.cz>
+
+	PR driver/31468
+	* gcc.c (process_command): Do not allow empty argument of -o option.
+
 2017-05-15  Renlin Li  <renlin.li@arm.com>
 
 	* config/aarch64/aarch64-protos.h (aarch64_expand_call): Declare.

gcc/gcc.c

@@ -4478,6 +4478,9 @@ process_command (unsigned int decoded_options_count,
 		       output_file);
     }
 
+  if (output_file != NULL && output_file[0] == '\0')
+    fatal_error (input_location, "output filename may not be empty");
+
   /* If -save-temps=obj and -o name, create the prefix to use for %b.
      Otherwise just make -save-temps=obj the same as -save-temps=cwd.  */
   if (save_temps_flag == SAVE_TEMPS_OBJ && save_temps_prefix != NULL)