This is a hack which works around the compiler bug:
To decide what cash-value is force-convert-from-real (R - cash-value): (- REAL_NUMBER_TY_to_NUMBER_TY({R}) -).
When play begins:
let R be force-convert-from-real 2.0 times holdings;
say "Number result: [2 times holdings]. Real number result: [R].";
Remember to take that line out in the next release of I7 when the bug is fixed.