re PR libgomp/83106 (libgomp/target.c:2671:2: error: ‘strncat’ specified bound 5…

re PR libgomp/83106 (libgomp/target.c:2671:2: error: ‘strncat’ specified bound 5 equals source length [-Werror=stringop-overflow=])

	PR libgomp/83106
	* target.c (gomp_target_init): Compute lengths just once and
	use them in both malloc size and subsequent copying.

From-SVN: r255080

libgomp/ChangeLog

+2017-11-22  Jakub Jelinek  <jakub@redhat.com>
+
+	PR libgomp/83106
+	* target.c (gomp_target_init): Compute lengths just once and
+	use them in both malloc size and subsequent copying.
+
 2017-11-17  Igor Tsimbalist  <igor.v.tsimbalist@intel.com>
 
 	* configure.ac: Set CET_FLAGS, update XCFLAGS and FCFLAGS.

libgomp/target.c

@@ -2656,20 +2656,24 @@ gomp_target_init (void)
     do
       {
 	struct gomp_device_descr current_device;
+	size_t prefix_len, suffix_len, cur_len;
 
 	next = strchr (cur, ',');
 
-	plugin_name = (char *) malloc (1 + (next ? next - cur : strlen (cur))
-				       + strlen (prefix) + strlen (suffix));
+	prefix_len = strlen (prefix);
+	cur_len = next ? next - cur : strlen (cur);
+	suffix_len = strlen (suffix);
+
+	plugin_name = (char *) malloc (prefix_len + cur_len + suffix_len + 1);
 	if (!plugin_name)
 	  {
 	    num_devices = 0;
 	    break;
 	  }
 
-	strcpy (plugin_name, prefix);
-	strncat (plugin_name, cur, next ? next - cur : strlen (cur));
-	strcat (plugin_name, suffix);
+	memcpy (plugin_name, prefix, prefix_len);
+	memcpy (plugin_name + prefix_len, cur, cur_len);
+	memcpy (plugin_name + prefix_len + cur_len, suffix, suffix_len + 1);
 
 	if (gomp_load_plugin_for_device (&current_device, plugin_name))
 	  {