Lahey Computer Systems, Inc.Fujitsu Ltd.

Fortran 95 (Win32) Language System

Full Fortran 77, 90, and 95

Speed. Dependability. Great Tech Support. Lahey/Fujitsu Fortran 95.
The standard for Fortran programming from the leader in Fortran language systems.

We've combined our 40 years of producing award-winning Fortran language systems with Fujitsu's compiler expertise and high-performance code generator to deliver the most-productive, best-supported Fortran 95 language system for the PC. Whether you write new Fortran programs or downsize existing applications, you need speed, dependability, and great tech support. You need LF Fortran v7.2!

LF Fortran v7.2 Delivers!

LF95 v7.2 is available in two configurations: Express and Professional:

LF95 Express includes the powerful Lahey/Fujitsu Fortran 95 optimizing compiler, linker, command line debugger, librarian, support for creating DLLs and calling the Windows APIs, online documentation, and free e-mail support. LF95 PRO adds Microsoft's Visual Studio 2008 Shell with Lahey's exclusive Fortran Integration, the Winteracter Starter Kit, WiSK, for creating Windows GUIs and displaying graphics, Polyhedron's Automake utility, Fujitsu's WinFDB Windows debugger, the Coverage Analysis Tool that detects unexecuted code and performs range-of-operation checking, the Sampler Tool (an execution profiler) that helps tune program performance, Fujitsu's Visual Analyzer, the Fujitsu SSL2 math library (an extensive library and a proven performer on Fujitsu mainframes and workstations) and the Fujitsu C compiler.

LF Fortran 95 Performance.

LF Fortran 95 7.2 offers improved execution performance on most Fortran 77 and 90 codes. The new optimizations help performance on Pentium(R) 4 and Xeon(TM) chips. "We tested v7.2 Win32 optimizations on a 2.4GHz P4 with 512 MB of PC2100 RAM, running Windows XP, using Polyhedronís ( Fortran benchmarks. Specifying the new switches -tp4, -sse2, -zfm, -o2, and -inline the 90 benchmarks ran an average of 15.4% faster and the 77 benchmarks 4.4% faster than they did when built with LF Fortran v7.0." 

LF Fortran 95 Optimizations.

Basic Optimization
  • Constant folding
  • Common subexpression elimination
  • Copy propagation
  • Strength Reduction
  • Algebraic simplifications
  • Dead code elimination
  • Peephole optimization
  • Loop invariant code motion
  • Transform array element to simple variable
  • Local Instruction scheduling
  • Address calculation optimization
  • Array optimization
Program Reconstruction Optimizations
  • Loop unrolling
  • Loop interchange
Procedure Optimization
  • Inlining mathematical functions
  • Stack optimization
  • Inline user-defined
  • Pentium/Pentium PRO/Pentium 4 instruction
  • Using fast input/output libraries
  • Prefetch Pentium III / Athlon
  • SSE2 instruction optimizations
  • Enable flush-to-zero mode for SSE2

Statically Link Fujitsu C and Borland C++ Object Files.

LF Fortran 95 supports static linking with Fujitsu C and Borland C++ Object Files. Combine your Fortran and C/C++ code into one executable. For the routines you don't want to develop yourself, you can also link with C/C++ routines from commercially available libraries. 

DLL Interfaces to Visual Basic, VC++, Borland C++, Delphi, Microsoft .NET languages.

Create 32-bit Windows DLLs from your Fortran routines and call the Fortran routines from 32-bit Windows programs created with Microsoft Visual Basic, Microsoft Visual C++, Borland C++, Borland Delphi, and Microsoft .NET languages. 

Win32 API Access.

LF Fortran 95 supports direct calls from Fortran to functions in the Win32 API. For a narrow range of applications, this might be the last little bit of glue you need to pull off your project. Note that this is not for the faint-hearted! You'll need to be a Windows programmer to get all but the most basic functionality. That's because the API was written to be called from C. And consequently, arguments need to be passed as C expects them. Structures and callback routines pose additional problems. Clearly, this would be a difficult way to build a Windows application from scratch.

Legacy Fortran Support.

LF Fortran 95 extends its language support in other directions adding many legacy Fortran features, including VAX structures and the various UNIX service routines. These features further facilitate your move to cost/performance efficiency on the PC platform:
  • Unlimited number of continuation lines in free or fixed source form 
  • DO UNTIL statement 
  • FIND statement 
  • STRUCTURE and END STRUCTURE statements 
  • UNION and END UNION statements 
  • MAP and END MAP statements 
  • RECORD statement 
  • Non-standard POINTER statement 
  • AUTOMATIC statement 
  • STATIC statement 
  • VALUE statement 
  • BYTE statement 
  • Hollerith constants 
  • Alternative forms of binary, octal, and hexadecimal constants 
  • Binary, octal, or hexadecimal constants in a DATA, declaration statement 
  • Period structure component separator 
  • Namelist input/output on internal file 
  • FORM = 'BINARY' 
  • TOTALREC specifier 
  • STATUS = 'SHR' 
  • Gw, $, \, and R edit descriptors 
  • LOC intrinsic function 

ANSI/ISO-Compliant Fortran 95.

LF Fortran 95 is a complete implementation of the ANSI/ISO Fortran 95 standard. Fortran 95 offers some small but important improvements over Fortran 90, including the ability to create your own elemental procedures, default initialization for structure components, the NULL intrinsic for initializing pointers, the FORALL construct, and a standard CPU_TIME intrinsic procedure. 

IEEE Standard 754 support
IEEE Standard 754 defines the representation and behavior of 32- and 64-bit floating point numbers. IEEE 754 support provides for consistency of basic computational results among platforms that use IEEE 754. An excellent overview of the standard is presented online by Steve Hollasch at A heavy-duty online discussion of floating point numbers and the standard is provided by David Goldberg at

Visual Studio 2008 Shell with Lahey's exclusive Fortran Integration.


Project system

The project is a basic building block that Visual Studio uses to create applications. A project will normally take a set of one or more source files and produce a compiled executable, but a project can also produce things like DLLs or static libraries, or do other sorts of processing. All the source files within a project are usually written in one programming language, and are compiled with one compiler. The LF95 integration package provides several type of projects, and allows users of VS2003 to automatically upgrade their native Fortran projects to VS2008. The LF95 project facility automatically scans all source files at build time and ensures all files are built in the proper order to satisfy module dependencies.

Win32 project and project item templates

On-line integrated help

The VS2008 integration package provides documentation that is integrated into Visual Studio help system. The comprehensive documentation covers the Fortran language, LF95 compiler usage, and Fortran-smart Visual Studio editing features:

Syntax coloring

Syntax coloring provides the ability to differentiate code elements based on color. For example, a keyword may appear in blue, comments may appear in green, while character strings might be maroon. The Fortran language allows variables and procedures to have the same names as keywords, and this can pose a problem for colorizers that do not have a strong parsing ability. Since the parser used in the Lahey colorizer is derived from a Fortran compiler, it is unlikely that is would be confused by an identifier with the same name as a keyword. The integration package allows the user to customize the colorizing scheme.

Expandable code

Expandable code can make the chore of navigating through sections of code easier by allowing you to collapse a region of code into a single line. This feature works at the module and procedure levels by default, but the user has the ability to add new outlining regions, or to remove existing outlining regions.

A portion of the collapsed code can be viewed by hovering the mouse over the box containing the "...":

Method tips for intrinsic functions

Parameter Info is a feature that helps the user write code by displaying information about intrinsic procedures as the user is typing. Parameter Info is currently implemented for all Fortran 95 intrinsic procedures, and Lahey extensions supported by LF95.
As a procedure invocation is typed, the open parenthesis character triggers the Parameter Info tooltip for the first argument:

As typing continues, each succeeding comma character that is typed will trigger a tooltip for the next parameter:

When a close parenthesis character is typed, the tooltip window is dismissed. The tooltip window is also dismissed whenever the cursor is moved outside of the area of the argument list.

Quick info for local and global variables

Quick Info provides the user with information about variables and intrinsic procedures by displaying an informational tooltip window when the mouse is hovered over a name. Quick Info is currently implemented for all Fortran 95 intrinsic procedures, Lahey extensions supported by LF95, and variables that are defined within the same file.

Block commenting and indenting

Block commenting is a feature that allows the user to quickly comment or uncomment selected blocks of code. Block indenting allows the user to change the indentation of a selected block of code. Both of these features work for code that is highlighted. If any portion of a line is highlighted, the feature works on the entire line. If there is no highlighted code, commenting or indenting will work on the single line where the cursor resides.

Brace matching

Parenthesis matching is a feature that locates a matching parenthesis and highlights the parenthesis pair. This feature can be quite useful when examining a complex statement. The following diagram shows a single multiline code statement with the matching braces highlighted with a light gray box:

Automation support

Automation is the ability to control Visual Studio, solutions and projects with software. It allows the user to programmatically control project creation and modification, to set project and file compilation options, and to build and execute projects.

MSBuild support

MSBuild is Microsoft's XML-based build system. It is integrated with Visual Studio, but it can also be used on the command line. The LF95 Project facility uses MSbuild when building projects. For a comprehensive description of MSBuild, see the MSDN documentation for msbuild.exe.

Visual SourceSafe support

The Fortran integration package supports the Visual SourceSafe VCS. From Visual Studio 2008, the user with Visual SourceSafe installed will be able to easily place entire Fortran solutions under version control. The user can check Fortran files and projects in and out with Visual Studio. Note that because the Fortran project system modifies the project file in order to update dependency information, it is necessary to check out the project file before building the project.

Fortran-Smart Windows Debugger

The WinFDB debugger provides a Windows graphical interface for debugging your Fortran code. 
Incrementally execute your program - Single step through your program. Step into or over calls to other routines. 
Stop on Break Points - Click in the margin of your source code to set break points. 
Examine Registers - Open the registers window to examine processor registers and flags. 
Visual Step - Visual Step mode allows the user to automatically step through the program at a comprehensible pace. 
Watch Variables - Open a watch window to show selected variable values in any active program unit.
Mixed-Language Programs - Debug programs created from LF Fortran 95 and Fujitsu C objects.

Other Development Tools

Complementing the Windows Development Environment, LF Fortran 95 includes the Microsoft's make utility (nmake), Automake make utility; Microsoft's library manager (lib) and Lahey's Library Manager (LM) for building and working with library files; and Microsoft's linker (link). 

Winteracter Starter Kit.

Use the Winteracter Starter Kit - WiSK - for creating true Windows programs with Fortran. WiSK is a subset of the Winteracter Library created by Interactive Software Services, Ltd. (Winteracter is available from Lahey.) Winteracter is a Fortran 95-callable, 32-bit, Windows, user-interface and graphics development kit. Derived from Winteracter, WiSK provides a library of subroutines for window management, input handling, dialog management, and high resolution graphics, plus custom versions of the visual menu and dialog designers. 

Click here to view/download WiSK examples.

Fujitsu Visual Analyzer. 

Fujitsu Visual Analyzer

Visually analyze the call structure and logic flow of your Fortran and C source code. Display a detailed cross reference of all the variables in the program and where modules and commons are defined and referenced. Show C global variable definitions and references as well. VA can help you understand someone else's code, detect subtle programming errors across multiple files, and verify compliance with the Fortran 95 standard. 

LF Fortran 95 beta tester Barry Santana says, "Fujitsu Visual Analyzer has been a great help in avoiding conflicts in the modifications. The help that Lahey Technical Support has provided quickly and without hassle has provided this project with a much needed shot in the arm! It has confirmed that my decision to switch to the Lahey compiler was correct. Thanks for all the help." 

Fujitsu Scientific Subroutine Library 2. 

The Fujitsu Scientific Subroutine Library 2 (SSL2) has been in use for years in Japan on Fujitsu mainframe and workstation hardware. SSL2 offers over 250 optimized routines in the following areas:

Linear Algebra
Matrix Storage Mode Conversion
Matrix Manipulation
Linear Equations and Matrix Inversion (Direct Method)
Least Squares Solution

Eigenvalues and Eigenvectors
Eigenvalues and Eigenvectors of a Real Matrix
Eigenvalues and Eigenvectors of a Complex Matrix
Eigenvalues and Eigenvectors of a Real Symmetric Matrix
Eigenvalues and Eigenvectors of a Hermitian Matrix
Eigenvalues and Eigenvectors of a Real Symmetric Band Matrix
Eigenvalues and Eigenvectors of a Real Symmetric Generalized Eigenproblem
Eigenvalues and Eigenvectors of a Real Symmetric Band Generalized Eigenproblem

Nonlinear Equations
Polynomial Equations
Transcendental Equations
Nonlinear Simultaneous Equations

Minimization of Function with a Variable
Unconstrained Minimization of Multivariable Function
Unconstrained Minimization of Sum of Squares of Functions (Nonlinear Least Squares Solution)
Linear Programming
Nonlinear Programming (Constrained Minimization of Multivariable Function)

Interpolation and Approximation

Discrete Real Fourier Transforms
Discrete Cosine Transforms
Discrete Sine Transforms
Discrete Complex Fourier Transforms 
Laplace Transform

Numerical Differentiation and Quadrature

Differential Equations

Special Functions
Elliptic Integrals
Exponential Integral
Sine and Cosine Integrals
Fresnel Integrals
Gamma Functions
Error Functions
Bessel Functions 
Normal Distribution Functions

Pseudo Random Numbers
Pseudo Random Generation
Pseudo Random Testing

Free Email Support.
Free e-mail, fax, and postal mail technical support available with LF Fortran 95. 

LF Fortran 95 Specifications

Compiler Switches  
-[n]ap Guarantee consistency of REAL and COMPLEX calculations
-[n]blas Link with optimized BLAS library
-block <value> Set default block size for OPEN statements
-[n]c Create object and/or module files without an executable
-[n]chk [<args>] Check substrings and array subscripts, non-common variables accessed before initialization, and mismatched procedure arguments
-[n]chkglobal Generate compiler error messages, and perform full compile and runtime checking
-[n]co Display compiler options
-[n]concc Support carriage control characters in console I/O
-[n]cover Generate information for use by the coverage tool
-[n]dal Deallocate allocatable arrays
-[n]dbl Extend REAL and COMPLEX variables, arrays, constants, and functions to KIND=8
-[n]dll Generate a dynamic link library
-[n]f95 Generate warnings for non-standard Fortran 95
-file <name> Ensure driver interprets file name as name of file and not a switch argument
-[n]fix Interpret source files as Fortran 95 fixed source form
-[n]g Generate debugger information
-i <path> Specify search path for Fortran INCLUDE files
-[n]in Equivalent to including an IMPLICIT NONE statement in each program unit
-[n]info Display informational messages at compile time
-[n]inline [<value>] Inline user-defined procedures
-[n]lapack Link with optimized LAPACK library
-[n]li Avoid recognizing non-standard Lahey intrinsic procedures
-[n]long Extend all default INTEGER variables, arrays, constants, and functions to KIND=8
-[n]lst [<args>] Create source listings
-[n]maxfatals <value> Specify maximum number of fatal errors allowed before stopping compilation
-ml <arg> Generate code compatible with other languages
-mldefault <arg> Specify default mixed language target
-mod <path> Specify search path for module files
-o <name> Override default object file name
-o0 Optimization level 0 - perform no optimization
-o1 Optimization level 1 - perform full optimization
-o2 -o1 plus loop and array optimizations
-out Specify output file name
-[n]pause Create pause after program completion
-[n]pca Prevent invoked subprograms from storing into constants
-[n]prefetch <value> Generate prefetch optimizations
-[n]private Set default block size for OPEN statements
-[n]quad Extend all double-precision REAL and COMPLEX variables, arrays, rays, constants, and functions to KIND=16
-[n]sav Allocate local variables in a compiler-generated SAVE area
-[n]ssl2 Link with optimized SSL II library
-[n]sse2 Optimize using SSE2 instructions
-[n]staticlib Static or dynamic linkinf of Fortran runtime libraries
-[n]staticlink Statically link with code produced by another supported language system
-[n]stchk Check for stack overflows
-[n]swm <args> Suppress warning messages
-t4 Generate code optimized for Intel 80386 or 80486 processor
-tpp Generate code optimized for Intel Pentium Pro, Pentium II, Pentium III, or Celeron processors, or generic counterparts
-tp4 Generate code optimized for Intel Pentium 4, Xeon, or generic counterparts
-[n]trace Include procedure traceback and line numbers in runtime error messages
-[n]trap <args> Trap numeric data processor (NDP) exceptions at runtime
-[n]unroll [<value>] Control loop unrolling
-[n]varheap [<value>] Allocate local variables on heap
-version Display version and owner information only
-[n]vsw Create a simple console-like Windows GUI application
-[n]w Generate warning messages
-wide Wide fixed form line length
-win Create Windows application
-winconsole Create Windows Console application
-[n]wisk Create application that uses the Winteracter Starter Kit (WiSK)
-[n]wo Generate warning messages for obsolescent Fortran 90 code
-[n]xref [<args>] Create cross-reference listings
-[n]zero Include variables initialized to zero
-[n]zfm Enable flush-to-zero mode for SSE2 instructions

LF Fortran 95 System Requirements


  • 1 GHz or higher, Intel or AMD processor (Pentium III or better)
  • 1 GB or more RAM
  • 1024x600 display (Recommended Minimum for Visual Studio)

Operating System

LF Fortran v7.2 and Visual Studio 2008 can be installed onto any of the following systems:
  • Windows 7 (32 and 64 bit)
  • Windows Vista (32 and 64 bit)
  • Windows Server 2008
  • Windows XP Service Pack 2 (SP2) or later
  • Windows Server 2003 w/SP1
  • Windows 2000 (command-line only)

Target Operating System

LF Fortran 95 applications are compatible with Microsoft Windows 7, Vista, XP, 2000, NT 4.0, Me, 98, and 95.