bad FP or bad saved FP at pointer-addr in call stack, can't read
 frame near frame-addr

    Facility: DEBUG, VMS Debugger

    Explanation: The debugger is attempting to chain down the call
    stack, following frame pointers. The FP register (if pointer-
    addr is "FFFFFFFF") or the saved frame pointer at location
    pointer-addr points to a frame at least part of which is not
    read accessible near location frame-addr.

    User Action: Determine what part of your code is writing into the
    FP register or overwriting the saved frame pointer on the call
    stack (or a preceding saved frame pointer) and correct it. Since
    the debugger looks at the call stack to symbolize addresses, you
    may suppress some of these messages by typing the command "SET
    MODE NOSYMBOLIC".