A GOTO statement that transfers control to a label variable was invalid. The possible causes are:

• The generation of the block that was active when the label variable was assigned was no longer active when the GOTO statement was run.
• The label variable was uninitialized.
• The element of the label array, to which control is to be transferred, does not exist in the program.
• An attempt has been made to transfer control to a block that is not within the scope of this task.

DCL L LABEL;
BEGIN;
A:  L = A;
END;
GOTO L;