CSA Preface Standards development within the Information Technology sector is harmonized with international standards development. Through the CSA Technical Committee on Information Technology (TCIT), Canadians serve as the SCC Mirror Committee (SMC) on ISO/IEC Joint Technical Committee 1 on Information Technology (ISO/IEC JTC1) for the Standards Council of Canada (SCC), the ISO member body for Canada and sponsor of the Canadian National Committee of the IEC. Also, as a member of the International Telecommunication Union (ITU), Canada participates in the International Telegraph and Telephone Consultative Committee (ITU-T). For brevity, this Standard will be referred to as \"CSA ISO/IEC 1539-1\" throughout. This Standard supersedes CAN/CSA-ISO/IEC 1539-1:12 (adopted ISO/IEC 1539-1:2010). At the time of publication, ISO/IEC 1539-1:2018 is available from ISO and IEC in English only. CSA Group will publish the French version when it becomes available from ISO and IEC. The International Standard, was reviewed by the CSA TCIT under the jurisdiction of the CSA Strategic Steering Committee on Information Technology and deemed acceptable for use in Canada. From time to time, ISO/IEC may publish addenda, corrigenda, etc. The TCIT will review these documents for approval and publication. For a listing, refer to the Current Standards Activities page at standardsactivities.csa.ca. This Standard has been formally approved, without modification, by the Technical Committee and has been developed in compliance with Standards Council of Canada requirements for National Standards of Canada. It has been published as a National Standard of Canada by CSA Group. Scope 1 This document specifies the form and establishes the interpretation of programs expressed in the base Fortran language. The purpose of this document is to promote portability, reliability, maintainability, and efficient execution of Fortran programs for use on a variety of computing systems. 2 This document specifies • the forms that a program written in the Fortran language can take • the rules for interpreting the meaning of a program and its data • the form of the input data to be processed by such a program, and • the form of the output data resulting from the use of such a program. 3 Except where stated otherwise, requirements and prohibitions specified by this document apply to programs rather than processors. 4 This document does not specify • the mechanism by which programs are transformed for use on computing systems, • the operations required for setup and control of the use of programs on computing systems • the method of transcription of programs or their input or output data to or from a storage medium • the program and processor behavior when this document fails to establish an interpretation except for the processor detection and reporting requirements in items (2) to (10) of 4.2 • the maximum number of images, or the size or complexity of a program and its data that will exceed the capacity of any particular computing system or the capability of a particular processor • the mechanism for determining the number of images of a program • the physical properties of an image or the relationship between images and the computational elements of a computing system • the physical properties of the representation of quantities and the method of rounding, approximating, or computing numeric values on a particular processor, except by reference to ISO/IEC/IEEE 60559:2011 under conditions specified in Clause 17, • the physical properties of input/output records, files, and units, or • the physical properties and implementation of storage.