Ada 16.1

GCC 16.1 is here, and with it comes the latest GNAT Ada compiler featuring new object-oriented extensions, improved generic handling, and enhanced Android support. Let's break down what's new.

GNAT Extensions — Constructor and Destructor

The headline feature in this release is the addition of Constructor and Destructor extensions, inspired by object-oriented programming in languages like C++. These add new construction and finalization mechanisms that differ from standard Ada, giving developers more control over object lifecycle management.

Implicit With

The new Implicit With feature allows a stand-alone use clause in the context clause of a compilation unit to imply an implicit with of the same library unit. This reduces boilerplate when commonly used packages are referenced together, making code cleaner and more maintainable.

Structural Generic Instantiation

Structural Generic Instantiation allows reference to an implicit instance of a generic unit, denoted directly by the unit's name and actual parameters rather than through a separately declared name. This simplifies generic usage in large Ada codebases.

Extended_Access Aspect

The Extended_Access aspect can be specified on a general access type declaration designating an unconstrained array subtype. It changes the pointer representation and allows easier interfacing with foreign languages. This enables creation of access-to-array-slice types, opening new possibilities for low-level systems programming in Ada.

Other Improvements

• VAST Verifier — A new Verifier for the Ada Semantic Tree (VAST), enabled with -gnatd_V, helps debug the compiler by checking properties of the produced Ada semantic tree.
• Ada 2022 — Semantic analysis of Ada 2022's Reduction Expressions has been enhanced.
• Ada.Containers — The Bounded_Indefinite_Holders unit has been added to the standard containers library.
• Accessibility rules — Various loopholes in the implementation of accessibility rules have been plugged.
• Android support — Improved Android target support for Ada applications.

Ada 16.1 ships as part of GCC 16.1, available now from gcc.gnu.org. Upgrade your GNAT toolchain to take advantage of these new features.