diff --git a/src/testdir/Make_dos.mak b/src/testdir/Make_dos.mak
index 5776a79..eda1a52 100644
--- a/src/testdir/Make_dos.mak
+++ b/src/testdir/Make_dos.mak
@@ -134,5 +134,5 @@
 
 test_options.res test_alot.res: opt_test.vim
 
-opt_test.vim: ../option.c gen_opt_test.vim
-	$(VIMPROG) -u NONE -S gen_opt_test.vim --noplugin --not-a-term ../option.c
+opt_test.vim: ../optiondefs.h gen_opt_test.vim
+	$(VIMPROG) -u NONE -S gen_opt_test.vim --noplugin --not-a-term ../optiondefs.h
diff --git a/src/testdir/Make_ming.mak b/src/testdir/Make_ming.mak
index 2ad34b9..671caa2 100644
--- a/src/testdir/Make_ming.mak
+++ b/src/testdir/Make_ming.mak
@@ -138,5 +138,5 @@
 
 test_options.res test_alot.res: opt_test.vim
 
-opt_test.vim: ../option.c gen_opt_test.vim
-	$(VIMPROG) -u NONE -S gen_opt_test.vim --noplugin --not-a-term ../option.c
+opt_test.vim: ../optiondefs.h gen_opt_test.vim
+	$(VIMPROG) -u NONE -S gen_opt_test.vim --noplugin --not-a-term ../optiondefs.h
diff --git a/src/testdir/Makefile b/src/testdir/Makefile
index 0efebb5..bcf2f8c 100644
--- a/src/testdir/Makefile
+++ b/src/testdir/Makefile
@@ -83,6 +83,8 @@
 RM_ON_START = tiny.vim small.vim mbyte.vim mzscheme.vim test.ok benchmark.out
 RUN_VIM = VIMRUNTIME=$(SCRIPTSOURCE) $(VALGRIND) $(VIMPROG) -f $(GUI_FLAG) -u unix.vim $(NO_INITS) -s dotest.in
 
+# Delete files that may interfere with running tests.  This includes some files
+# that may result from working on the tests, not only from running them.
 clean:
 	-rm -rf *.out *.failed *.res *.rej *.orig XfakeHOME Xdir1 Xfind
 	-rm -f opt_test.vim test.log test_result.log messages
@@ -176,8 +178,8 @@
 	$(RUN_VIMTEST) -u gui_preinit.vim -U gui_init.vim $(NO_PLUGINS) -S runtest.vim $<
 	@rm vimcmd
 
-opt_test.vim: ../option.c gen_opt_test.vim
-	$(VIMPROG) -u NONE -S gen_opt_test.vim --noplugin --not-a-term ../option.c
+opt_test.vim: ../optiondefs.h gen_opt_test.vim
+	$(VIMPROG) -u NONE -S gen_opt_test.vim --noplugin --not-a-term ../optiondefs.h
 
 test_xxd.res:
 	XXD=$(XXDPROG); export XXD; $(RUN_VIMTEST) $(NO_INITS) -S runtest.vim test_xxd.vim
diff --git a/src/version.c b/src/version.c
index 929a4c6..f76dde7 100644
--- a/src/version.c
+++ b/src/version.c
@@ -758,6 +758,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    2028,
+/**/
     2027,
 /**/
     2026,