Error Occurs When Parameter is Negative

[lygwzy89]

There is a multiplier in the code, and one of its parameters is:
defparam \mult_mac .coef_a_0 = -1053;
When reading in this code, the following error occurs:
ERROR: Parameter mult_mac.coef_a_0 with non-constant value!
The direct reason for this is that the parameter's type is AST_NEG, which triggers the error. The parameter's child type is AST_CONSTANT.
How can this issue be resolved?
Thanks!