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(a) The FSF's Front-Cover Text is:

A GNU Manual

(b) The FSF's Back-Cover Text is:

You have freedom to copy and modify this GNU Manual, like GNU software. Copies published by the Free Software Foundation raise funds for GNU development.

Table of Contents

• Contributing
• Portability
• Interface
• Languages
• Source Tree
  • Configure Terms
  • Top Level
  • gcc Directory
    • Subdirectories
    • Configuration
      • Config Fragments
      • System Config
      • Configuration Files
    • Build
    • Makefile
    • Library Files
    • Headers
    • Documentation
      • Texinfo Manuals
      • Man Page Generation
      • Miscellaneous Docs
    • Front End
      • Front End Directory
      • Front End Config
    • Back End
  • Test Suites
    • Test Idioms
    • C Tests
• Passes
• Trees
  • Deficiencies
  • Tree overview
    • Macros and Functions
    • Identifiers
    • Containers
  • Types
  • Scopes
    • Namespaces
    • Classes
  • Declarations
  • Functions
    • Function Basics
    • Function Bodies
  • Attributes
  • Expression trees
• RTL
  • RTL Objects
  • RTL Classes
  • Accessors
  • Flags
  • Machine Modes
  • Constants
  • Regs and Memory
  • Arithmetic
  • Comparisons
  • Bit-Fields
  • Vector Operations
  • Conversions
  • RTL Declarations
  • Side Effects
  • Incdec
  • Assembler
  • Insns
  • Calls
  • Sharing
  • Reading RTL
• Machine Desc
  • Overview
  • Patterns
  • Example
  • RTL Template
  • Output Template
  • Output Statement
  • Constraints
    • Simple Constraints
    • Multi-Alternative
    • Class Preferences
    • Modifiers
    • Machine Constraints
  • Standard Names
  • Pattern Ordering
  • Dependent Patterns
  • Jump Patterns
  • Looping Patterns
  • Insn Canonicalizations
  • Expander Definitions
  • Insn Splitting
  • Including Patterns
  • Peephole Definitions
    • define_peephole
    • define_peephole2
  • Insn Attributes
    • Defining Attributes
    • Expressions
    • Tagging Insns
    • Attr Example
    • Insn Lengths
    • Constant Attributes
    • Delay Slots
    • Function Units
  • Conditional Execution
  • Constant Definitions
• Target Macros
  • Target Structure
  • Driver
  • Run-time Target
  • Per-Function Data
  • Storage Layout
  • Type Layout
  • Escape Sequences
  • Registers
    • Register Basics
    • Allocation Order
    • Values in Registers
    • Leaf Functions
    • Stack Registers
  • Register Classes
  • Stack and Calling
    • Frame Layout
    • Exception Handling
    • Stack Checking
    • Frame Registers
    • Elimination
    • Stack Arguments
    • Register Arguments
    • Scalar Return
    • Aggregate Return
    • Caller Saves
    • Function Entry
    • Profiling
    • Tail Calls
  • Varargs
  • Trampolines
  • Library Calls
  • Addressing Modes
  • Condition Code
  • Costs
  • Scheduling
  • Sections
  • PIC
  • Assembler Format
    • File Framework
    • Data Output
    • Uninitialized Data
    • Label Output
    • Initialization
    • Macros for Initialization
    • Instruction Output
    • Dispatch Tables
    • Exception Region Output
    • Alignment Output
  • Debugging Info
    • All Debuggers
    • DBX Options
    • DBX Hooks
    • File Names and DBX
    • SDB and DWARF
    • VMS Debug
  • Cross-compilation
  • Mode Switching
  • Target Attributes
  • Misc
• Host Config
• Fragments
  • Target Fragment
  • Host Fragment
• Collect2
• Header Dirs
• Funding
• GNU Project
• Copying
• GNU Free Documentation License
• Contributors
• Option Index
• Index

Node:Top, Next:Contributing

Next:Contributing

Introduction

This manual documents the internals of the GNU compilers, including how to port them to new targets and some information about how to write front ends for new languages. It corresponds to GCC version 3.1. The use of the GNU compilers is documented in a separate manual. See Top.

This manual is mainly a reference manual rather than a tutorial. It discusses how to contribute to GCC (see Contributing), the characteristics of the machines supported by GCC as hosts and targets (see Portability), how GCC relates to the ABIs on such systems (see Interface), and the characteristics of the languages for which GCC front ends are written (see Languages). It then describes the GCC source tree structure and build system, some of the interfaces to GCC front ends, and how support for a target system is implemented in GCC.

Additional tutorial information is linked to from http://gcc.gnu.org/readings.html.

• Contributing: How to contribute to testing and developing GCC.
• Portability: Goals of GCC's portability features.
• Interface: Function-call interface of GCC output.
• Languages: Languages for which GCC front ends are written.
• Source Tree: GCC source tree structure and build system.
• Passes: Order of passes, what they do, and what each file is for.
• Trees: The source representation used by the C and C++ front ends.
• RTL: The intermediate representation that most passes work on.
• Machine Desc: How to write machine description instruction patterns.
• Target Macros: How to write the machine description C macros and functions.
• Host Config: Writing the xm-machine.h file.
• Fragments: Writing the t-target and x-host files.
• Collect2: How collect2 works; how it finds ld.
• Header Dirs: Understanding the standard header file directories.

• Funding: How to help assure funding for free software.
• GNU Project: The GNU Project and GNU/Linux.

• Copying: GNU General Public License says how you can copy and share GCC.
• GNU Free Documentation License: How you can copy and share this manual.
• Contributors: People who have contributed to GCC.

• Option Index: Index to command line options.
• Index: Index of concepts and symbol names.