VHDL error at <location>: variable must be constrained

(ID: 10529)

CAUSE: In a VHDL Design File (.vhd) at the specified location, you used an unconstrained variable. However, in the context in which the variable is being used, the variable must be constrained.
ACTION: Changed the unconstrained variable to a constrained variable.

See also:

Sections,, and 8.5 of the IEEE Std 1076-1993 IEEE Standard VHDL Language Reference Manual