diff --git a/src/testdir/test_vim9_cmd.vim b/src/testdir/test_vim9_cmd.vim
index ece3f73..22b1896 100644
--- a/src/testdir/test_vim9_cmd.vim
+++ b/src/testdir/test_vim9_cmd.vim
@@ -301,12 +301,21 @@
   CheckDefAndScriptFailure(lines, 'E1135:', 3)
 
   lines =<< trim END
+      g:cond = 0
+      if g:cond
+      elseif 'text' garbage
+      endif
+  END
+  CheckDefAndScriptFailure(lines, 'E488:', 3)
+
+  lines =<< trim END
+      g:cond = 0
       if g:cond
       elseif [1]
       endif
   END
-  CheckDefFailure(lines, 'E1012:', 2)
-  CheckScriptFailure(['vim9script'] + lines, 'E745:', 3)
+  CheckDefFailure(lines, 'E1012:', 3)
+  CheckScriptFailure(['vim9script'] + lines, 'E745:', 4)
 
   lines =<< trim END
       g:cond = 'text'
diff --git a/src/version.c b/src/version.c
index 37d3832..4890e2c 100644
--- a/src/version.c
+++ b/src/version.c
@@ -754,6 +754,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    3711,
+/**/
     3710,
 /**/
     3709,
diff --git a/src/vim9compile.c b/src/vim9compile.c
index 3f72c7f..2ed1f0e 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -7888,6 +7888,7 @@
     cctx->ctx_skip = save_skip;
     if (!ends_excmd2(arg, skipwhite(p)))
     {
+	clear_ppconst(&ppconst);
 	semsg(_(e_trailing_arg), p);
 	return NULL;
     }
@@ -7901,7 +7902,10 @@
 	// The expression result is a constant.
 	v = tv_get_bool_chk(&ppconst.pp_tv[0], &error);
 	if (error)
+	{
+	    clear_ppconst(&ppconst);
 	    return NULL;
+	}
 	cctx->ctx_skip = v ? SKIP_NOT : SKIP_YES;
 	clear_ppconst(&ppconst);
 	scope->se_u.se_if.is_if_label = -1;