diff --git a/runtime/syntax/Makefile b/runtime/syntax/Makefile
index f3b578c..945308f 100644
--- a/runtime/syntax/Makefile
+++ b/runtime/syntax/Makefile
@@ -11,6 +11,8 @@
 # VALGRIND = valgrind --tool=memcheck --leak-check=yes --num-callers=45 --log-file=valgrind.$*
 
 # ENVVARS = LC_ALL=C LANG=C LANGUAGE=C
+# Run the syntax tests with a C locale
+ENVVARS = LC_ALL=C
 
 RUN_VIMTEST = VIMRUNTIME=$(VIMRUNTIME) $(VALGRIND) $(ENVVARS) ../$(VIMPROG) -f $(GUI_FLAG)
 
@@ -25,11 +27,11 @@
 	@# the "vimcmd" file is used by the screendump utils
 	@echo "../$(VIMPROG)" > testdir/vimcmd
 	@echo "$(RUN_VIMTEST)" >> testdir/vimcmd
-	VIMRUNTIME=$(VIMRUNTIME) $(VIMPROG) --clean --not-a-term $(DEBUGLOG) -u testdir/runtest.vim
+	VIMRUNTIME=$(VIMRUNTIME) $(ENVVARS) $(VIMPROG) --clean --not-a-term $(DEBUGLOG) -u testdir/runtest.vim
 	@# FIXME: Temporarily show the whole file to find out what goes wrong
 	@#if [ -f testdir/messages ]; then tail -n 6 testdir/messages; fi
 	@if [ -f testdir/messages ]; then cat testdir/messages; fi
 
 
 clean testclean:
-	rm -f testdir/failed/* testdir/done/* testdir/vimcmd testdir/messages
+	rm -f testdir/failed/* testdir/done/* testdir/vimcmd testdir/messages testdir/Xtestscript
diff --git a/runtime/syntax/testdir/runtest.vim b/runtime/syntax/testdir/runtest.vim
index 80f1eff..d2ce3d1 100644
--- a/runtime/syntax/testdir/runtest.vim
+++ b/runtime/syntax/testdir/runtest.vim
@@ -237,11 +237,12 @@
 call Message('skipped: ' .. skipped_count)
 call AppendMessages('== SUMMARY ==')
 
-" Matching "if 1" at the start.
-endif
-
 if len(failed_tests) > 0
   " have make report an error
   cquit
 endif
+
+" Matching "if 1" at the start.
+endif
+
 qall!
diff --git a/src/testdir/shared.vim b/src/testdir/shared.vim
index 4d008a0..9479efb 100644
--- a/src/testdir/shared.vim
+++ b/src/testdir/shared.vim
@@ -300,7 +300,8 @@
   endif
   let cmd .= ' --not-a-term'
   let cmd .= ' --gui-dialog-file guidialogfile'
-  let cmd = substitute(cmd, 'VIMRUNTIME=\S\+', '', '')
+  " remove any environment variables
+  let cmd = substitute(cmd, '[A-Z_]*=\S\+ *', '', 'g')
 
   " If using valgrind, make sure every run uses a different log file.
   if cmd =~ 'valgrind.*--log-file='
diff --git a/src/version.c b/src/version.c
index 6beeabb..91abfe1 100644
--- a/src/version.c
+++ b/src/version.c
@@ -705,6 +705,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    91,
+/**/
     90,
 /**/
     89,