"/*" BEGIN(comment_ml);
<comment_ml>[^*\n]* /* eat anything that's not a '*' */
<comment_ml>"*"+[^*/\n]* /* eat up '*'s not followed by '/'s */
"/*" BEGIN(comment_ml);
<comment_ml>[^*\n]* /* eat anything that's not a '*' */
<comment_ml>"*"+[^*/\n]* /* eat up '*'s not followed by '/'s */