Dynamic Linking with the ARM Compiler toolchain

Application Note 242


Table of Contents

1. Conventions and feedback
2. Introduction
2.1. Purpose
2.2. Additional material
3. Linking overview and background
3.1. Linking background
3.2. Symbol definitions and references
3.3. Static linking and relocations
4. How is dynamic linking different to static linking?
4.1. Dynamic linking concepts
4.2. Dynamic linking benefits
4.3. Disadvantages of dynamic linking
5. Alternatives to dynamic linking
5.1. Symbol definition files
5.2. Jump tables
5.3. Overlays
6. ELF overview and background
6.1. Introduction
6.2. ELF file structure
6.2.1. ELF headers
6.2.2. ELF sections
7. Technical overview of dynamic linking
7.1. Dynamic linker
7.2. What does the dynamic linker need to do?
7.2.1. BPABI and post-linking
7.3. Locating dynamic content
7.4. Dynamic relocations
7.4.1. BPABI relocation example
7.5. Handling function calls between modules
7.5.1. Direct PLTs
7.5.2. Indirect PLTs
7.6. Handling data accesses between modules
8. Controlling what symbols can be dynamically linked
8.1. Symbol visibility
8.1.1. Setting symbol visibility
8.2. Populating the dynamic symbol table
8.3. Symbol preemption
8.3.1. SysV symbol preemption example
8.4. Symbol versioning
9. Dynamic linking models
9.1. Bare-metal
9.2. DLL-like
9.2.1. Base Platform Application Binary Interface (BPABI) linking model
9.2.2. The base platform linking model
9.3. SysV
9.3.1. Building SysV executables
9.3.2. Building shared objects
9.3.3. Symbol visibility rules
9.4. Choosing an appropriate model
9.4.1. Single address space versus multiple address spaces
9.4.2. SysV versus BPABI
9.4.3. BPABI versus base platform
10. Dynamic linking with the ARM Compiler toolchain
10.1. Controlling symbol visibility in the ARM Compiler toolchain
10.1.1. Compiler (armcc)
10.1.2. Assembler (armasm)
10.1.3. Linker (armlink)
10.1.4. Steering files
10.1.5. Dynamic symbol table rules
10.1.6. ELF reader and converter (fromelf)
10.1.7. Other dynamic image related linker (armlink) options
10.2. Controlling dynamic section contents
Glossary

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Product Status

The information in this document is final, that is for a developed product.

Revision History
Revision ADecember 2010First release
Copyright © 2010 ARM. All rights reserved.ARM DAI 0242A
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