| Copyright © 2002-2005 ARM Limited. All rights reserved. | ARM DUI 0206F |
| Non-Confidential | |
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| Home > System V Shared Libraries > Using SVr4 shared libraries > Building an ARM Linux executable |
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Use the --sysv command-line option to generate
an SVr4 formatted ELF executable file that can be used on ARM Linux.
If you use --sysv, the linker ignores any
scatter file that you specify on the command line.
The base of an executable is 0x8000 by
default. The linker creates a dynamic executable when shared object
files are given on the command line.
When the linker finds a shared object on the command line, it is included in the list of libraries to be added to the executable file (see Library searching, selection, and scanning for details).
If you are working on ARM Linux, be aware of the following:
The Linux kernel performs all copying and zero initialization of the executable file.
RW data is not compressed.
An executable is always entered in ARM state.
For an example library that retargets the ARM C library to
run under ARM Linux see the main examples directory, in ...\linux.
A shared object is an extension of the static and dynamic
scatter-loading file described in Building an ARM
Linux executable. The base address of the load region
is set at 0 and is then relocated by the Linux
dynamic linker.
If your shared object contains any exported RW data, you are
required to use position independent code and data. In this case,
you must compile or assemble your files using --apcs /fpic,
and link the files into a shared object using the --fpic linker
option.
Use the --shared command-line option to build
an SVr4 shared object.
A shared object usually has no entry point. However, it is possible to set an entry point. This must be done if the object you are building is the dynamic linker.
To comply with the Linux Standard Base Specification v1.2,
an executable file must contain a section named .note.ABI-tag of
type SHT_NOTE, structured as a note section as documented
in the ELF specification.
You can use the command-line option --linux_abitag to
specify the minimum compatible kernel version
for the executable file you are building, for example:
armlink ... --sysv --linux_abitag 2.2.5 main.o
This links main.o to the ARM C library
for a static executable that is defined as being compatible with
Linux kernel v2.2.5 or later. If you specify any shared objects
on the command line that demand a newer kernel,
the kernel requirements in the output file are incremented to match.
For full details on using the Linux ABI tag and Standard Base
Specification, see http://www.linuxbase.org.
| Copyright © 2002-2005 ARM Limited. All rights reserved. | ARM DUI 0206F |
| Non-Confidential | |
| PDF version | |
| Home > System V Shared Libraries > Using SVr4 shared libraries > Building an ARM Linux executable |