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Chapter 8. Assembler Directives

Warning: .space has a completely different meaning for HPPA targets; use .block as a substitute. See

[HP9000 Series 800 Assembly Language Reference Manual] (HP 92432 90001) for the meaning of the

.space directive. Section 19.5 HPPA Assembler Directives, for a summary.

On the AMD 29K, this directive is ignored; it is accepted for compatibility with other AMD 29K

assemblers.

Warning: In most versions of the gnu assembler, the directive .space has the effect of .block Chapter 9

Machine Dependent Features.

8.86.

.stabd, .stabn, .stabs

There are three directives that begin

.stab

. All emit symbols (Chapter 6 Symbols), for use by sym 

bolic debuggers. The symbols are not entered in the

as

hash table: they cannot be referenced elsewhere

in the source file. Up to five fields are required:

string

This is the symbol's name. It may contain any character except

\000

, so is more general than

ordinary symbol names. Some debuggers used to code arbitrarily complex structures into symbol

names using this field.

type

An absolute expression. The symbol's type is set to the low 8 bits of this expression. Any bit

pattern is permitted, but

ld

and debuggers choke on silly bit patterns.

other

An absolute expression. The symbol's "other" attribute is set to the low 8 bits of this expression.

desc

An absolute expression. The symbol's descriptor is set to the low 16 bits of this expression.

value

An absolute expression which becomes the symbol's value.

If a warning is detected while reading a

.stabd

,

.stabn

, or

.stabs

statement, the symbol has

probably already been created; you get a half formed symbol in your object file. This is compatible

with earlier assemblers!

.stabd type , other , desc

The "name" of the symbol generated is not even an empty string. It is a null pointer, for compat 

ibility. Older assemblers used a null pointer so they didn't waste space in object files with empty

strings.

The symbol's value is set to the location counter, relocatably. When your program is linked, the

value of this symbol is the address of the location counter when the

.stabd

was assembled.

.stabn type , other , desc , value

The name of the symbol is set to the empty string

""

.