VSI OpenVMS
          VSI Fortran for OpenVMS
          User Manual
             Document Number: DO-DFRTUM-01A
             Publication Date: May 2020
             This manual provides information about the VSI Fortran program development
             environment on VSI OpenVMS systems.
             Revision Update Information: This is a new manual.
             Operating System and Version: VSI OpenVMS Integrity Version 8.4-1H1
                              VSI OpenVMS Alpha Version 8.4-2L1
             Software Version: VSI Fortran Version 8.3-3 for OpenVMS
             VMS Software, Inc., (VSI)
             Bolton, Massachusetts, USA
        VSI Fortran for OpenVMS User Manual
        Copyright © 2020 VMS Software, Inc. (VSI), Bolton, Massachusetts, USA
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        The VSI OpenVMS documentation set is available on CD.
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                           VSI Fortran for OpenVMS User Manual
           Preface ...................................................................................................................................  xv
             1. About VSI ....................................................................................................................  xv
             2. Intended Audience ........................................................................................................  xv
             3. Document Structure ......................................................................................................  xv
             4. Related Documents .....................................................................................................  xvii
             5. VSI Encourages Your Comments ................................................................................ xviii
             6. Conventions ............................................................................................................... xviii
           Chapter 1. Getting Started ...................................................................................................  1
             1.1. Fortran Standards Overview .........................................................................................  1
             1.2. VSI Fortran Programming Environment ........................................................................  1
             1.3. Commands to Create and Run an Executable Program ...................................................  4
             1.4. Creating and Running a Program Using a Module and Separate Function ........................  5
                1.4.1. Commands to Create the Executable Program ..................................................... 6
                1.4.2. Running the Sample Program ............................................................................. 7
                1.4.3. Debugging the Sample Program ......................................................................... 8
             1.5. Program Development Stages and Tools ........................................................................ 8
           Chapter 2. Compiling VSI Fortran Programs .................................................................. 11
             2.1. Functions of the Compiler ..........................................................................................  11
             2.2. FORTRAN Command Syntax, Use, and Examples ....................................................... 12
                2.2.1. Specifying Input Files and Source Form ...........................................................  12
                2.2.2. Specifying Multiple Input Files ........................................................................  13
                2.2.3. Creating and Using Module Files .....................................................................  14
                   2.2.3.1. Creating Module Files ........................................................................... 14
                   2.2.3.2. Using Module Files ..............................................................................  15
                2.2.4. Using Include Files and Include Text Library Modules ......................................  16
                   2.2.4.1. Using Include Files and INCLUDE Statement Forms .............................. 16
                   2.2.4.2. INCLUDE Statement Forms for Including Text Library Modules ............. 17
                   2.2.4.3. Using Include Text Library Modules for a Specified Library Name ........... 18
                   2.2.4.4. Using Include Text Library Modules for an Unspecified Library
                   Name ................................................................................................................ 19
                2.2.5. Specifying Output Files ...................................................................................  21
                2.2.6. Examples of the FORTRAN Command ............................................................  22
                   2.2.6.1. Naming the Object File ......................................................................... 22
                   2.2.6.2. Compiler Source Checking Only (No Object File) ..................................  22
                   2.2.6.3. Requesting a Listing File and Contents ..................................................  22
                   2.2.6.4. Compiling Multiple Files ......................................................................  22
                   2.2.6.5. Requesting Additional Compile-Time and Run-Time Checking ................ 23
                   2.2.6.6. Checking Fortran 90 or 95 Standard Conformance .................................. 23
                   2.2.6.7. Requesting Additional Optimizations .....................................................  24
             2.3. FORTRAN Command Qualifiers ................................................................................. 24
                2.3.1. FORTRAN Command Qualifier Syntax ............................................................  24
                2.3.2. Summary of FORTRAN Command Qualifiers ................................................... 24
                2.3.3. /ALIGNMENT — Data Alignment ................................................................... 32
                2.3.4. /ANALYSIS_DATA – Create Analysis Data File ............................................... 35
                2.3.5. /ANNOTATIONS — Code Descriptions ...........................................................  35
                2.3.6. /ARCHITECTURE — Architecture Code Instructions (Alpha only) .................... 37
                2.3.7. /ASSUME — Compiler Assumptions ...............................................................  38
                2.3.8. /AUTOMATIC — Data Storage .......................................................................  42
                2.3.9. /BY_REF_CALL — Character Literal Argument Passing ..................................  42
                2.3.10. /CCDEFAULT — Carriage Control for Terminals ............................................ 42
                2.3.11. /CHECK — Generate Code for Run-Time Checking ........................................ 43
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                       VSI Fortran for OpenVMS User Manual
            2.3.12. /CONVERT — Unformatted Numeric Data Conversion ...................................  46
            2.3.13. /D_LINES — Debugging Statement Indicator, Column 1 .................................  48
            2.3.14. /DEBUG — Object File Traceback and Symbol Table .....................................  48
            2.3.15. /DIAGNOSTICS — Create Diagnostics File ...................................................  49
            2.3.16. /DML — Invoke Fortran DML Preprocessor ...................................................  50
            2.3.17. /DOUBLE_SIZE — DOUBLE PRECISION Data Size .................................... 50
            2.3.18. /ERROR_LIMIT — Limit Compiler Messages ................................................ 51
            2.3.19. /EXTEND_SOURCE — Line Length for Fixed-Form Source ........................... 51
            2.3.20. /F77 — FORTRAN IV or FORTRAN-77 Compatibility ................................... 52
            2.3.21. /FAST — Request Fast Run-Time Performance ...............................................  52
            2.3.22. /FLOAT — Specify Floating-Point Format in Memory ..................................... 52
            2.3.23. /GRANULARITY — Control Shared Memory Access to Data ......................... 55
            2.3.24. /IEEE_MODE — Control IEEE Arithmetic Exception Handling ....................... 55
            2.3.25. /INCLUDE — Add Directory for INCLUDE and Module File Search ............... 57
            2.3.26. /INTEGER_SIZE — Integer and Logical Data Size .........................................  59
            2.3.27. /LIBRARY — Specify File as Text Library ..................................................... 59
            2.3.28. /LIST — Request Listing File ........................................................................  60
            2.3.29. /MACHINE_CODE — Request Machine Code in Listing File .......................... 61
            2.3.30. /MATH_LIBRARY — Fast or Accurate Math Library Routines (Alpha
            only) ......................................................................................................................... 61
            2.3.31. /MODULE — Placement of Module Files ....................................................... 62
            2.3.32. /NAMES — Control Case of External Names .................................................  62
            2.3.33. /OBJECT — Specify Name or Prevent Object File Creation ............................. 63
            2.3.34. /OLD_F77 — Use Old FORTRAN 77 Compiler (Alpha only) ..........................  63
            2.3.35. /OPTIMIZE — Specify Compiler Optimizations .............................................. 63
            2.3.36. /PAD_SOURCE — Pad Source Lines with Spaces ........................................... 69
            2.3.37. /REAL_SIZE — Floating-Point Data Size ....................................................... 69
            2.3.38. /RECURSIVE — Data Storage and Recursion ................................................. 70
            2.3.39. /REENTRANCY — Specify Threaded or Asynchronous Reentrancy ................  71
            2.3.40. /ROUNDING_MODE — Specify IEEE Floating-Point Rounding Mode ............ 71
            2.3.41. /SEPARATE_COMPILATION — Control Compilation Unit Use in Object
            Files .........................................................................................................................  73
            2.3.42. /SEVERITY — Specify Compiler Diagnostic Severity ..................................... 73
            2.3.43. /SHOW — Control Source Content in Listing File ........................................... 74
            2.3.44. /SOURCE_FORM — Fortran 90/95 Source Form ...........................................  75
            2.3.45. /STANDARD — Perform Fortran 90/95 Standards Checking ...........................  75
            2.3.46. /SYNCHRONOUS_EXCEPTIONS — Report Exceptions More Precisely
            (Alpha only) .............................................................................................................  77
            2.3.47. /SYNTAX_ONLY — Do Not Create Object File .............................................  77
            2.3.48. /VERSION — Display the VSI Fortran Version Number .................................. 78
            2.3.49. /TIE — Enable Code for Shared Translated Images .........................................  78
            2.3.50. /VMS — Request Compaq Fortran 77 for OpenVMS VAX Compatibility .......... 78
            2.3.51. /WARNINGS — Warning Messages and Compiler Checking ...........................  79
         2.4. Creating and Maintaining Text Libraries ...................................................................... 81
            2.4.1. Using the LIBRARY Commands ...................................................................... 83
            2.4.2. Naming Text Library Modules .........................................................................  83
         2.5. Using CDD/Repository ............................................................................................... 84
            2.5.1. Accessing CDD/Repository from VSI Fortran Programs ....................................  85
            2.5.2. VSI Fortran and CDD/Repository Data Types ...................................................  86
         2.6. Compiler Limits, Diagnostic Messages, and Error Conditions .......................................  87
            2.6.1. Compiler Limits ..............................................................................................  87
            2.6.2. Compiler Diagnostic Messages and Error Conditions ......................................... 88
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