The WEAK_GLOBAL attribute specifies that  an  object  is  linked
  only  when it is specifically included in the linking operation.
  To resolve a weak reference, the linker searches only the  named
  input  modules.   You  can specify an identifier to indicate the
  name by which the corresponding object is known to the linker.

  Syntax:

     [WEAK_GLOBAL]

  or,

     [WEAK_GLOBAL(identifier)]

  or,

     [WEAK_GLOBAL('string_literal')]

  The 'identifier' is the name of the  identifier  passed  to  the
  linker.  If you omit the identifier, the name of the variable is
  used.

  The 'string-literal' passes a specified string  literal  to  the
  linker unmodified.

  See the "HP Pascal Language Reference Manual" for  the  complete
  description of using the WEAK_GLOBAL attribute.