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Chapter 10: Expressions and Symbols in Debugger Commands
Symbolic Referencing
In C, static variables local to a module can only be accessed by functions in
that module. In the debugger, static variables local to a module can be
accessed either when a function is active in that module or when the variable is
qualified by the module name in which it is defined. A static variable that is
local to a function can only be accessed by the function in which it was
declared, unless it is qualified by the module and function in which it is defined.
Static functions can only be accessed when the function is in the current
module, unless the function is qualified by the module in which it is defined.
Automatic
Automatic variables are declared inside a function and are accessible only to
that function. Storage for these variables is allocated on the stack when the
function is called and released when the function returns. Automatic variables
do not have an initial value (their values are not retained between function
calls).
You can access an automatic (local) variable when it is local to the current
function, or when its function is on the stack. Use the stack-level prefix
@< stack_level> to access an automatic variable in a function on the stack.
Register
Register variables are also declared inside a function and are accessible only to
that function. Storage for these variables is allocated in a specific hardware
register when the function is called and released when the function returns.
Register variables do not have an initial value (their values are not retained
between function calls).
A register variable is accessible when it is local to the current function, or
when its function is on the stack.
Note
Breakpoints cannot be set on accesses to register variables. If you need to set
breakpoints on a variable, make sure that it is allocated on the stack by
declaring its type as automatic.
Data Types
All symbols and expressions have an associated data type. Assembly language
modules may contain variables with the types BYTE, WORD, or LONG. The
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