Many programs define hundreds of constant symbols (e.g., CR=13), and typically an include file is used to include the definitions of these symbols. Normally all symbols, including these, are listed in a symbol or cross-reference table. NOCONSTANTS can be used to ignore these constant symbols in the symbol/cross-reference table, effectively "cleaning up" the listing. If localsymbols is in effect, NOCONSTANTS also inhibits constant symbols from being placed into the object module.
Note: A constant symbol is different from a label defined in an absolute section.