node_modules/uncrustify/tests/input/c/nl-comment.c

/**
 * This is your typical header comment
 */
 int foo(int bar)
 {
    int idx;
    int res = 0;     // trailing comment
                   // that spans two lines
    /* multi-line comment
    */
    idx = 50;
    /* single line comment */
    for (idx = 1; idx < bar; idx++)
       /* comment in virtual braces */
       res += idx;

    res *= idx;       // some comment

                      // almost continued, but a NL in between

    i++;
// col1 comment in level 1
// second comment
   return(res);
}

   // col1 comment in level 0
 // and another