int lang_struct_sw_mb(int i){
    int a = i;
    switch (a){                           /* all clauses end with break statement */
        case 1: {/*...*/ break;}
        case 2: {/*...*/ a++; break;}
        default: {/*...*/ break;}
    }  

    switch (a){
        case 1:
          a++;                            /* break statement missing at end of this clause */
        case 3:  {      /* 'Missing break' warning issued here:
                         * the previous clause does not end with a break statement, so
                         * execution will fall through into this one.
                         */
          a++;
          break;
        }
        default:
          a--;          /* 'Missing break' warning issued here:
                         * there is no break statement at the end of this clause, which is
                         * the final clause in the switch statement.
                         */
    }

    return a;
}