2 area – ARM VERSION 1.2 User Manual

Page 334

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Directives Reference

7-52

Copyright © 2000, 2001 ARM Limited. All rights reserved.

ARM DUI 0068B

7.7.2

AREA

The

AREA

directive instructs the assembler to assemble a new code or data section.

Sections are independent, named, indivisible chunks of code or data that are
manipulated by the linker. See ELF sections and the AREA directive on page 2-15 for
more information.

Syntax

AREA sectionname{,attr}{,attr}...

where:

sectionname

is the name that the section is to be given.

You can choose any name for your sections. However, names starting
with a digit must be enclosed in bars or a missing section name error is
generated. For example,

|1_DataArea|

.

Certain names are conventional. For example,

|.text|

is used for code

sections produced by the C compiler, or for code sections otherwise
associated with the C library.

attr

are one or more comma-delimited section attributes. Valid attributes are:

ALIGN=expression

By default, ELF sections are aligned on a 4-byte boundary.

expression

can have any integer value from 0 to 31. The

section is aligned on a 2

expression

-byte boundary. For example,

if expression is 10, the section is aligned on a 1KB boundary.
This is not the same as the way that the

ALIGN

directive is

specified. See ALIGN on page 7-50.

Note

Do

not

use

ALIGN=0

or

ALIGN=1

for code sections.

ASSOC=section

section

specifies an associated ELF section.

sectionname

must

be included in any link that includes

section

CODE

Contains machine instructions.

READONLY

is the default.

COMDEF

Is a common section definition. This ELF section can contain
code or data. It must be identical to any other section of the
same name in other source files.

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