4.9.29 Global Directive

The GLOBAL identifier_list directive declares a list of comma-separated symbols. If the symbols are defined within the current module, they are made public. If the symbols are not defined in the current module, they are made references to public symbols defined in external modules. Thus to use the same symbol in two modules the GLOBAL directive must be used at least twice: once in the module that defines the symbol to make that symbol public and again in the module that uses the symbol to link in with the external definition.

For example:

GLOBAL  lab1,lab2,lab3