NAG Fortran Compiler Release 7.1 Release Note

1 Introduction

Release 7.1 of the NAG Fortran Compiler is a major update.

Customers upgrading from a previous release of the NAG Fortran Compiler will need a new licence key for this release.

See KLICENCE.txt for more information about Kusari Licence Management.

2 Release Overview

Release 7.1 of the NAG Fortran Compiler supports all of Fortran 2008, in particular:

Substantial additional support for Fortran 2018 has been added, in particular:

Support for OpenMP programming has been improved by enabling undefined variable checking in OpenMP programs. Additionally, some minor features from newer OpenMP specifications have also been added.

Finally, there is also additional error checking available, and the bundled tools have some additional capabilities.

3 Compatibility

3.1 Compatibility with Release 7.0

Release 7.1 is compatible with Release 7.0, except that files compiled with the -C=calls option will need to be recompiled if they contain a procedure with a procedure pointer argument, or a reference to such a procedure.

3.2 Compatibility with Release 6.2

On MacOS the 32-bit ABI mode accessible via -abi=32 has been removed; consequently only 64-bit compilation is supported and the -abi= switch has been removed entirely.

Other than this, Release 7.1 is fully compatible with Release 6.2 except when coarrays are used, or when the -C=calls option is used for a subroutine that has an alternate return. Any program that uses these features will need to be recompiled.

3.3 Compatibility with Release 6.1

Programs which use features from HPF (High Performance Fortran), for example the ILEN intrinsic function or the HPF_LIBRARY module, are no longer supported.

The previously deprecated -abi=64 option on Linux x86-64 has been withdrawn. This option provided an ABI with 64-bit pointers but 32-bit object sizes and subscript arithmetic, and was only present for compatibility with Release 5.1 and earlier.

With the exception of HPF support and the deprecated option removal, Release 7.1 of the NAG Fortran Compiler is fully compatible with Release 6.1.

3.4 Compatibility with Release 6.0

With the exception of HPF support and the deprecated option removal, Release 7.1 of the NAG Fortran Compiler is compatible with Release 6.0 except that programs that use allocatable arrays of “Parameterised Derived Type” will need to be recompiled (this only affects module variables and dummy arguments).

3.5 Compatibility with Releases 5.3.1, 5.3 and 5.2

With the exception of HPF support and the deprecated option removal, Release 7.1 of the NAG Fortran Compiler is fully compatible with Release 5.3.1. It is also fully compatible with Releases 5.3 and 5.2, except that on Windows, modules or procedures whose names begin with a dollar sign ($) need to be recompiled.

For a program that uses the new “Parameterised Derived Types” feature, it is strongly recommended that all parts of the program that may allocate, deallocate, initialise or copy a polymorphic variable whose dynamic type might be a parameterised derived type, should be compiled with Release 7.1.

3.6 Compatibility with Release 5.1

Release 7.1 of the NAG Fortran Compiler is compatible with NAGWare f95 Release 5.1 except that:

4 New Fortran 2008 Features

5 New Fortran 2018 Features

6 Additional OpenMP support

7 Additional error checking

8 Miscellaneous enhancements