PR c++/77489 -- Reorganize abi warning check

	PR c++/77489
	* mangle.c (write_discriminator): Reorganize abi warning check.

From-SVN: r244580

gcc/cp/ChangeLog

+2017-01-18  Markus Trippelsdorf  <markus@trippelsdorf.de>
+
+	PR c++/77489
+	* mangle.c (write_discriminator): Reorganize abi warning check.
+
 2017-01-18  Nathan Sidwell  <nathan@acm.org>
 
 	* cp-tree.h: Clarify exception spec node comment.

gcc/cp/mangle.c

@@ -1964,11 +1964,12 @@ write_discriminator (const int discriminator)
   if (discriminator > 0)
     {
       write_char ('_');
-      if (abi_version_at_least (11) && discriminator - 1 >= 10)
+      if (discriminator - 1 >= 10)
 	{
-	  write_char ('_');
 	  if (abi_warn_or_compat_version_crosses (11))
 	    G.need_abi_warning = 1;
+	  if (abi_version_at_least (11))
+	    write_char ('_');
 	}
       write_unsigned_number (discriminator - 1);
       if (abi_version_at_least (11) && discriminator - 1 >= 10)