• New implementation-defined aspects and pragmas:
    • Local_Restrictions, which specifies that a particular subprogram does not violate one or more local restrictions, nor can it call a subprogram that is not subject to the same requirements.
    • User_Aspect_Definition and User_Aspect, which provide a mechanism for avoiding textual duplication if some set of aspect specifications is needed in multiple places.
  • New implementation-defined aspects and pragmas for verification of the SPARK 2014 subset of Ada:
    • Always_Terminates, which provides a condition for a subprogram to necessarily complete (either return normally or raise an exception).
    • Ghost_Predicate, which introduces a subtype predicate that can reference Ghost entities.
    • Exceptional_Cases, which lists exceptions that might be propagated by the subprogram with side effects in the context of its precondition and associates them with a specific postcondition.
    • Side_Effects, which indicates that a function should be handled like a procedure with respect to parameter modes, Global contract, exceptional contract and termination: it may have output parameters, write global variables, raise exceptions and not terminate.
  • The new attributes and contracts have been applied to the relevant parts of the Ada runtime library, which has been subsequently proven to be correct with SPARK 2014.
  • Support for the LoongArch architecture.
  • Support for vxWorks 7 Cert RTP has been removed.
  • Additional hardening improvements. For more information reltated to hardening options, refer to the GCC Instrumentation Options and the GNAT Reference Manual, Security and Hardening Features.
  • Improve style checking for redundant parentheses with -gnatyz
  • New switch -gnateH to force reverse Bit_Order threshold to 64.
  • Experimental features:
    • Storage Model: this feature proposes to redesign the concepts of Storage Pools into a more efficient model allowing higher performances and easier integration with low footprint embedded run-times.
    • String Interpolation: allows for easier string formatting. Further clean up and improvements to the GNAT code.