diff --git a/plugins/excel/ms-formula-read.c b/plugins/excel/ms-formula-read.c
index 96f754e..d942c7b 100644
--- a/plugins/excel/ms-formula-read.c
+++ b/plugins/excel/ms-formula-read.c
@@ -1024,6 +1024,8 @@ excel_parse_formula1 (MSContainer const *container,
 	guint8 const *array_data0 = mem + length;
 	guint8 const *array_data = array_data0;
 
+	g_printerr ("l=%d al=%d\n", length, array_length);
+
 	int len_left = length;
 	GnmExprList *stack = NULL;
 	gboolean error = FALSE;
@@ -1465,6 +1467,8 @@ excel_parse_formula1 (MSContainer const *container,
 					GnmValue *elem;
 					guint8 val_type;
 
+					g_printerr ("delta = %zd\n", (size_t)(array_data - array_data0));
+
 					CHECK_FORMULA_ARRAY_LEN(1);
 					val_type = GSF_LE_GET_GUINT8 (array_data);
 					array_data++;
