15.42 GBLA, GBLL, and GBLS

The GBLA, GBLL, and GBLS directives declare and initialize global variables.

Syntax

gblx variable

where:

gblx

is one of GBLA, GBLL, or GBLS.

variable

is the name of the variable. variable must be unique among symbols within a source file.

Usage

The GBLA directive declares a global arithmetic variable, and initializes its value to 0.

The GBLL directive declares a global logical variable, and initializes its value to {FALSE}.

The GBLS directive declares a global string variable and initializes its value to a null string, "".

Using one of these directives for a variable that is already defined re-initializes the variable.

The scope of the variable is limited to the source file that contains it.

Set the value of the variable with a SETA, SETL, or SETS directive.

Global variables can also be set with the --predefine assembler command-line option.

Examples

The following example declares a variable objectsize, sets the value of objectsize to 0xFF, and then uses it later in a SPACE directive:

            GBLA    objectsize    ; declare the variable name
objectsize  SETA    0xFF          ; set its value
            .
            .                     ; other code
            .
            SPACE   objectsize    ; quote the variable

The following example shows how to declare and set a variable when you invoke armasm. Use this when you want to set the value of a variable at assembly time. --pd is a synonym for --predefine.

armasm --predefine "objectsize SETA 0xFF" sourcefile -o objectfile
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