GNAT User’s Guide Supplement for GNAT Pro Safety-Critical and GNAT Pro High-Security

GNAT, The GNU Ada Development Environment

Version 20.0w

Date: Oct 17, 2018

AdaCore

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being “GNAT Reference Manual”, and with no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License.

• 1. About This Guide
  • 1.1. What This Guide Contains
  • 1.2. What You Should Know Before Reading This Guide
  • 1.3. Related Information
  • 1.4. Conventions
• 2. The High Integrity Philosophy
• 3. Using GNAT Pro Features Relevant to High Integrity
  • 3.1. Exceptions and the High-Integrity Profiles
  • 3.2. Allocators and the High-Integrity Profiles
  • 3.3. Array and Record Assignments and the High-Integrity Profiles
  • 3.4. Object-Oriented Programming and the High-Integrity Profiles
  • 3.5. Functions Returning Unconstrained Objects
  • 3.6. Controlling Implicit Conditionals and Loops
  • 3.7. Controlling Use of Conditional Operators
  • 3.8. Avoiding Elaboration Code
  • 3.9. Removal of Deactivated Code
  • 3.10. Traceability from Source Code to Object Code
  • 3.11. Optimization issues
  • 3.12. Other useful features
  • 3.13. Compilation options for GNAT Pro Safety-Critical and GNAT Pro High-Security
    • 3.13.1. Compiler Switches
    • 3.13.2. gnatbind Switches
• 4. The Predefined Profiles
  • 4.1. Choosing a Predefined Profile
  • 4.2. The Zero Footprint Profile
    • 4.2.1. The -nostdlib Switch
    • 4.2.2. Ada Restrictions in the Zero Footprint Profile
    • 4.2.3. Predefined Packages in the Zero Footprint Profile
    • 4.2.4. Thread Registration Issues
    • 4.2.5. Pragmas Automatically Enabled in the Zero Footprint Profile
    • 4.2.6. Exceptions and the Last Chance Handler - ZFP and Ravenscar SFP
  • 4.3. The Cert Profile
    • 4.3.1. Exceptions and the Last Chance Handler - Cert and Ravenscar Cert Profiles
    • 4.3.2. Secondary Stack
    • 4.3.3. Thread Registration
    • 4.3.4. Dynamic Allocation
    • 4.3.5. Exponentiation
    • 4.3.6. 64-bit Numeric Types
    • 4.3.7. Utility Routines
  • 4.4. The Ravenscar Profiles
    • 4.4.1. Ada Restrictions in the Ravenscar Profiles
    • 4.4.2. Ada Features Permitted in the Ravenscar Profiles
    • 4.4.3. Pragmas Automatically Enabled in the Ravenscar Profiles
    • 4.4.4. Non-tasking Predefined Packages in the Ravenscar Profiles
    • 4.4.5. Interrupt Handling in the Ravenscar Profiles
  • 4.5. The Extended Ravenscar Profiles
    • 4.5.1. Protected Entries
    • 4.5.2. Relative Delay Statements
    • 4.5.3. Additional Non-Tasking Restrictions Removed
    • 4.5.4. Default Profile
• 5. The GNAT Configurable Run Time Facility
  • 5.1. Standard Run-Time Mode
  • 5.2. The Configurable Run Time
  • 5.3. Run-Time Libraries and Objects
    • 5.3.1. GNAT Pro Run-Time Library
    • 5.3.2. C Library
    • 5.3.3. Math Library
    • 5.3.4. Internal GCC Library
    • 5.3.5. Startup / Cleanup Code
  • 5.4. How Object Dependencies are Generated
    • 5.4.1. Explicit with Clauses
    • 5.4.2. Compiler-Generated Calls to GNAT Pro Run-Time Primitives
    • 5.4.3. Pragma Import
    • 5.4.4. Back-End Generated Calls to Library Functions
  • 5.5. How The Run Time Library Is Configured
    • 5.5.1. Use of Configuration Pragmas
    • 5.5.2. Specification of Configuration Parameters
    • 5.5.3. Restricting the Set of Run-Time Units
  • 5.6. Naming the Run-Time Library
  • 5.7. Configuring a Special Purpose Library

• GNU Free Documentation License