Evaluation of Students from Schools that Don't Have Class Rank

Considering that the Common Data Set for Texas says they don’t even consider a student’s GPA, and consider class rank as “Very Important,” how does an AdCom evaluate a student coming from a school that doesn’t give out class ranks? They don’t even report what percentage of enrolled students had GPA’s of 3.25-3.50, 3.50-3.75, etc. Thanks