-int* concat_tab(int tab1[], unsigned tab_size1, int tab2[], unsigned tab_size2, int tab_dest[]) {
- int* rt = create_tab(tab_dest, tab_size1 + tab_size2);
+/* one must free the two source tabs in case they will be unused after to concatenation */
+int* concat_tab(int tab1[], unsigned tab_size1, int tab2[], unsigned tab_size2) {
+ int* tab_dest = NULL;
+ tab_dest = create_tab(tab_dest, tab_size1 + tab_size2);