Integer Literals are limited to 64 Bit ints.

[tquatmann]

The IntegerLiteralExpressions store their value in a 64 Bit integer. This could not be sufficient in some cases, in particular when using the ExpressionParser to parse rational functions (e.g. in a DRN file).

For example, this has been an issue here.

The obvious solution would be to use NumberTraits<RationalNumber>::IntegerType here, similar to the RationalLiteralExpressions. Of course, this could produce some overhead, e.g., when dealing with PRISM or JANI files. It might be worth investigating this overhead. A compromise solution could be to only use arbitrary precision integer literals in exact or parametric mode.