Download fortran compiler for windows 10 for free. Development Tools downloads - GFortran by morgan.persson@ddg.lth.se and many more programs are available for instant and free download. Getting a Fortran compiler. In order to use Fortran, you have to have a Fortran compiler installed on your machine. While there are excellent commercial compilers from the Portland Group and from Intel, my own preference is for open source solutions, so I use gfortran, which is free and supports Fortran 90. There is another widely used free.

• Fortran 90 Compiler Online
• Fortran 90 Compiler For Mac

Next: Preprocessing Options, Previous: Option Summary, Up: Invoking GNU Fortran [Contents][Index]

2.2 Options controlling Fortran dialect

The following options control the details of the Fortran dialectaccepted by the compiler:

-ffree-form

-ffixed-form

Specify the layout used by the source file. The free form layoutwas introduced in Fortran 90. Fixed form was traditionally used inolder Fortran programs. When neither option is specified, the sourceform is determined by the file extension.

-fall-intrinsics

This option causes all intrinsic procedures (including the GNU-specificextensions) to be accepted. This can be useful with -std=f95 toforce standard-compliance but get access to the full range of intrinsicsavailable with gfortran. As a consequence, -Wintrinsics-stdwill be ignored and no user-defined procedure with the same name as anyintrinsic will be called except when it is explicitly declared EXTERNAL.

-fallow-argument-mismatch

Some code contains calls to external procedures with mismatchesbetween the calls and the procedure definition, or with mismatchesbetween different calls. Such code is non-conforming, and will usuallybe flagged with an error. This options degrades the error to awarning, which can only be disabled by disabling all warnings via-w. Only a single occurrence per argument is flagged by thiswarning. -fallow-argument-mismatch is implied by-std=legacy.

Using this option is strongly discouraged. It is possible toprovide standard-conforming code which allows different types ofarguments by using an explicit interface and TYPE(*).

Fortran 90 Compiler Online

-fallow-invalid-boz

A BOZ literal constant can occur in a limited number of contexts instandard conforming Fortran. This option degrades an error conditionto a warning, and allows a BOZ literal constant to appear where theFortran standard would otherwise prohibit its use.

-fd-lines-as-code

-fd-lines-as-comments

Enable special treatment for lines beginning with d or Din fixed form sources. If the -fd-lines-as-code option isgiven they are treated as if the first column contained a blank. If the-fd-lines-as-comments option is given, they are treated ascomment lines.

-fdec

DEC compatibility mode. Enables extensions and other features that mimicthe default behavior of older compilers (such as DEC).These features are non-standard and should be avoided at all costs.For details on GNU Fortran’s implementation of these extensions see thefull documentation.

Other flags enabled by this switch are:-fdollar-ok-fcray-pointer-fdec-char-conversions-fdec-structure-fdec-intrinsic-ints-fdec-static-fdec-math-fdec-include-fdec-blank-format-item-fdec-format-defaults

If -fd-lines-as-code/-fd-lines-as-comments are unset, then-fdec also sets -fd-lines-as-comments.

-fdec-char-conversions

Enable the use of character literals in assignments and DATA statementsfor non-character variables.

-fdec-structure

Enable DEC STRUCTURE and RECORD as well as UNION,MAP, and dot (’.’) as a member separator (in addition to ’%’). This isprovided for compatibility only; Fortran 90 derived types should be usedinstead where possible.

-fdec-intrinsic-ints

Enable B/I/J/K kind variants of existing integer functions (e.g. BIAND, IIAND,JIAND, etc...). For a complete list of intrinsics see the full documentation.

-fdec-math

Enable legacy math intrinsics such as COTAN and degree-valued trigonometricfunctions (e.g. TAND, ATAND, etc...) for compatability with older code.

-fdec-static

Enable DEC-style STATIC and AUTOMATIC attributes to explicitly specifythe storage of variables and other objects.

-fdec-include

Enable parsing of INCLUDE as a statement in addition to parsing it asINCLUDE line. When parsed as INCLUDE statement, INCLUDE does not have tobe on a single line and can use line continuations.

-fdec-format-defaults

Enable format specifiers F, G and I to be used without width specifiers,default widths will be used instead.

-fdec-blank-format-item

Enable a blank format item at the end of a format specification i.e. nothingfollowing the final comma.

-fdollar-ok

Allow ‘$’ as a valid non-first character in a symbol name. Symbols that start with ‘$’ are rejected since it is unclear which rules toapply to implicit typing as different vendors implement different rules.Using ‘$’ in IMPLICIT statements is also rejected.

-fbackslash

Change the interpretation of backslashes in string literals from a singlebackslash character to “C-style” escape characters. The followingcombinations are expanded a, b, f, n,r, t, v, , and 0 to the ASCIIcharacters alert, backspace, form feed, newline, carriage return,horizontal tab, vertical tab, backslash, and NUL, respectively.Additionally, xnn, unnnn andUnnnnnnnn (where each n is a hexadecimal digit) aretranslated into the Unicode characters corresponding to the specified codepoints. All other combinations of a character preceded by areunexpanded.

-fmodule-private

Set the default accessibility of module entities to PRIVATE.Use-associated entities will not be accessible unless they are explicitlydeclared as PUBLIC.

-ffixed-line-length-n

Set column after which characters are ignored in typical fixed-formlines in the source file, and, unless -fno-pad-source, through whichspaces are assumed (as if padded to that length) after the ends of shortfixed-form lines.

Popular values for n include 72 (thestandard and the default), 80 (card image), and 132 (correspondingto “extended-source” options in some popular compilers).n may also be ‘none’, meaning that the entire line is meaningfuland that continued character constants never have implicit spaces appendedto them to fill out the line.-ffixed-line-length-0 means the same thing as-ffixed-line-length-none.

-fno-pad-source

By default fixed-form lines have spaces assumed (as if padded to that length)after the ends of short fixed-form lines. This is not done either if-ffixed-line-length-0, -ffixed-line-length-none orif -fno-pad-source option is used. With any of those optionscontinued character constants never have implicit spaces appendedto them to fill out the line.

-ffree-line-length-n

Set column after which characters are ignored in typical free-formlines in the source file. The default value is 132.n may be ‘none’, meaning that the entire line is meaningful.-ffree-line-length-0 means the same thing as-ffree-line-length-none.

-fmax-identifier-length=n

Specify the maximum allowed identifier length. Typical values are31 (Fortran 95) and 63 (Fortran 2003 and Fortran 2008).

-fimplicit-none

Specify that no implicit typing is allowed, unless overridden by explicitIMPLICIT statements. This is the equivalent of addingimplicit none to the start of every procedure.

-fcray-pointer

Enable the Cray pointer extension, which provides C-like pointerfunctionality.

-fopenacc

Enable the OpenACC extensions. This includes OpenACC !$accdirectives in free form and c$acc, *$acc and!$acc directives in fixed form, !$ conditionalcompilation sentinels in free form and c$, *$ and!$ sentinels in fixed form, and when linking arranges for theOpenACC runtime library to be linked in.

-fopenmp

Enable the OpenMP extensions. This includes OpenMP !$omp directivesin free formand c$omp, *$omp and !$omp directives in fixed form,!$ conditional compilation sentinels in free formand c$, *$ and !$ sentinels in fixed form, and when linking arranges for the OpenMP runtime library to be linkedin. The option -fopenmp implies -frecursive.

-fno-range-check

Disable range checking on results of simplification of constantexpressions during compilation. For example, GNU Fortran will givean error at compile time when simplifying a = 1. / 0.With this option, no error will be given and a will be assignedthe value +Infinity. If an expression evaluates to a valueoutside of the relevant range of [-HUGE():HUGE()],then the expression will be replaced by -Inf or +Infas appropriate.Similarly, DATA i/Z'FFFFFFFF'/ will result in an integer overflowon most systems, but with -fno-range-check the value will“wrap around” and i will be initialized to -1 instead.

-fdefault-integer-8

Set the default integer and logical types to an 8 byte wide type. This optionalso affects the kind of integer constants like 42. Unlike-finteger-4-integer-8, it does not promote variables with explicitkind declaration.

-fdefault-real-8

Set the default real type to an 8 byte wide type. This option also affectsthe kind of non-double real constants like 1.0. This option promotesthe default width of DOUBLE PRECISION and double real constantslike 1.d0 to 16 bytes if possible. If -fdefault-double-8is given along with fdefault-real-8, DOUBLE PRECISIONand double real constants are not promoted. Unlike -freal-4-real-8,fdefault-real-8 does not promote variables with explicit kinddeclarations.

-fdefault-real-10

Set the default real type to an 10 byte wide type. This option also affectsthe kind of non-double real constants like 1.0. This option promotesthe default width of DOUBLE PRECISION and double real constantslike 1.d0 to 16 bytes if possible. If -fdefault-double-8is given along with fdefault-real-10, DOUBLE PRECISIONand double real constants are not promoted. Unlike -freal-4-real-10,fdefault-real-10 does not promote variables with explicit kinddeclarations.

-fdefault-real-16

Set the default real type to an 16 byte wide type. This option also affectsthe kind of non-double real constants like 1.0. This option promotesthe default width of DOUBLE PRECISION and double real constantslike 1.d0 to 16 bytes if possible. If -fdefault-double-8is given along with fdefault-real-16, DOUBLE PRECISIONand double real constants are not promoted. Unlike -freal-4-real-16,fdefault-real-16 does not promote variables with explicit kinddeclarations.

-fdefault-double-8

Set the DOUBLE PRECISION type and double real constantslike 1.d0 to an 8 byte wide type. Do nothing if thisis already the default. This option prevents -fdefault-real-8,-fdefault-real-10, and -fdefault-real-16,from promoting DOUBLE PRECISION and double real constants like1.d0 to 16 bytes.

-finteger-4-integer-8

Promote all INTEGER(KIND=4) entities to an INTEGER(KIND=8)entities. If KIND=8 is unavailable, then an error will be issued.This option should be used with care and may not be suitable for your codes.Areas of possible concern include calls to external procedures,alignment in EQUIVALENCE and/or COMMON, generic interfaces,BOZ literal constant conversion, and I/O. Inspection of the intermediaterepresentation of the translated Fortran code, produced by-fdump-tree-original, is suggested.

-freal-4-real-8

-freal-4-real-10

Fortran 90 Compiler For Mac

-freal-4-real-16

-freal-8-real-4

-freal-8-real-10

-freal-8-real-16

Promote all REAL(KIND=M) entities to REAL(KIND=N) entities.If REAL(KIND=N) is unavailable, then an error will be issued.The -freal-4- flags also affect the default real kind and the-freal-8- flags also the double-precision real kind. All otherreal-kind types are unaffected by this option. The promotion is alsoapplied to real literal constants of default and double-precision kindand a specified kind number of 4 or 8, respectively.However, -fdefault-real-8, -fdefault-real-10,-fdefault-real-10, and -fdefault-double-8 take precedencefor the default and double-precision real kinds, both for real literalconstants and for declarations without a kind number.Note that for REAL(KIND=KIND(1.0)) the literal may get promoted andthen the result may get promoted again.These options should be used with care and may not be suitable for yourcodes. Areas of possible concern include calls to external procedures,alignment in EQUIVALENCE and/or COMMON, generic interfaces,BOZ literal constant conversion, and I/O and calls to intrinsic procedureswhen passing a value to the kind= dummy argument. Inspection of theintermediate representation of the translated Fortran code, produced by-fdump-fortran-original or -fdump-tree-original, is suggested.

-std=std

Specify the standard to which the program is expected to conform,which may be one of ‘f95’, ‘f2003’, ‘f2008’,‘f2018’, ‘gnu’, or ‘legacy’. The default value forstd is ‘gnu’, which specifies a superset of the latestFortran standard that includes all of the extensions supported by GNUFortran, although warnings will be given for obsolete extensions notrecommended for use in new code. The ‘legacy’ value isequivalent but without the warnings for obsolete extensions, and maybe useful for old non-standard programs. The ‘f95’,‘f2003’, ‘f2008’, and ‘f2018’ values specify strictconformance to the Fortran 95, Fortran 2003, Fortran 2008 and Fortran2018 standards, respectively; errors are given for all extensionsbeyond the relevant language standard, and warnings are given for theFortran 77 features that are permitted but obsolescent in laterstandards. The deprecated option ‘-std=f2008ts’ acts as an alias for‘-std=f2018’. It is only present for backwards compatibility withearlier gfortran versions and should not be used any more.

-ftest-forall-temp

Enhance test coverage by forcing most forall assignments to use temporary.

Next: Preprocessing Options, Previous: Option Summary, Up: Invoking GNU Fortran [Contents][Index]

Free Fortran Compilers

There are a number of free Fortran 77 and 90 compilers available on thenet.The one I have been using in my Fortran courses at York isGNU, which implements Fortran 77 and adds several Fortran 90 features. Thanks to Prof. Clive Page (Dept of Physics & Astronomy, University of Leicester, UK)for providing the compiler and for valuable advice on Fortran in general.

You can download the 1999 version of this compiler (version 2.95 of gcc) along with the SLATEC library (Version 4.1, July 1993), from this page. Thepackage should run under all versions ofWindows.All the needed files are packed in one zipped file(Fort99.zip) of about 6MB.

(If for some reason you need the older DOS/EMX version,which does not include a library and does not run under Windows XP, then youcan download it from my old page.)

DOWNLOAD

• Create the directory F
  The new folder must be immediately under the root of your hard disk. You can do this by double-clicking MyComputer, then double-clicking your hard drive (usually C:), and then selecting New Folder from the File menu and calling the folder F.
  
• Download the file Fort99.zip (5,820,239 bytes).
  You can do this by right-clicking the mouse on the above link, and choosing Save Target As.... In the Save As window that appears, locate the F folder, and save the file in it.
  
• Unzip the downloaded file into F.
  Yon can do this by locating the file (starting from MyComputer) and simply double-clicking it to launch the zip/unzip program. Make sure to specify that all files should be extracted immediately under the F folder.
  Note: If the unzip program does not give you the option to specify the extraction location, let it extract the content to anywhere and then move the extracted folders (using cut and paste) to F. When done, you should see the four folders G77, SLATEC, MINE, and YORK appearing in F.
  

That's it! You use the compiler through CLI, the command-line interface (akaterminal, command prompt, or DOS) after setting two environmentvariables, PATH and LIBRARY_PATH, as shown below.

USAGE

You store your programs in the FYork directory, compile themusing: f2exe, and create library object files using f2lib.Here is a very short program to test the compiler and the configuration: Use any editor to create this program (simply copy and paste) and save it as a text file in the FYork directory under the name test.for. Youcan, of course, use any editor you like as long as you can save the filein text format and with the extension you want. Notepad, for example, uses text but insists on using the txt extension (unless you override by double-quoting) while MS-Word insists on its propriety format (unless you explicitly override). I highly recommend using the Crimsoneditor, which can be downloaded from the on-line Lab-1 (see below).

To compile your program, start a CLI session (by launching the command promptprogram, usually in the Accessories group) and issue these two commands:These set the environment so that your computer would know where the compilerand its libraries are located.
Note: these two commands must be issued every time you start a CLI session. Youcan optionally automate this step by adding these two variables to the system-wideenvironment using the Control Panel.
You can now compile and run your program by typing:If the first command returned an error then the directory was not created (ornamed) correctly. If the second command was not recognized, or complained that a library is missing, then the environmentvariables were not set correctly (you can issue the set command without any arguments to inspect all environment variables).

More information on using the compiler can be found in theon-line Labs at theFortran@York site.

LANGUAGE

The FG77doc directory has a detailed reference to the language, which is largly ANSI Fortran-77but with some Fortran-90 features added (see below).

The above Fortran@York sitecontains a quick reference guide, lab, and SLATEC usage examples.If you are already familiar with Fortran then the following points may beall you need to know about this compiler:

1. Control Structures
   You can use either the old (goto-based) or the new (structured) control flow (or mix them in the same program). Support of the 'ugly goto' is meant for existing code only, and any new development should avoid it.
2. Style
   You can write your source using either the old style code (column 7) or the newer free-form.
3. Compilation Command
   The above f2exe command is just a batch file that invokes g77, the 'real' compilation command. The command: directs the compiler to compile the file prog.for and stores the output in the file prog.exe. The -ffree-form switch indicates free-form style (remove it if you are using the old style).
4. Comments
   In free-form style, use ! for both full-line and in-line comments. In the old style, use a 'C' in column-1.
5. Statement Continuation
   In free-form style, you can continue a statement on the next line by ending it with an ampersand '&'. In the old style, put a character in column-6.
6. Path Separator
   When referring to files (e.g. in the file=' ' parameter of the OPEN statement) use a forward slash '/' or two consecutive backslashes ' rather than a backslash to delimit directories. This is because the backslash ' denotes an escape sequence in strings.
7. I/O Unit Numbers
   Not all unit numbers are allowed in the OPEN statement. In particular, unit 5 is 'pre-connected' to the keyboard. Units 10 through 99 seem to work well with disk files.
8. Fortran-90 Features
   These include: Automatic arrays in subprograms, zero length strings, character constants may be enclosed in double quotes (') as well as single quotes, cycle and exit, the DOUBLE COMPLEX type, DO WHILE, the END decoration, KIND, IMPLICIT NONE, INCLUDE statements, list-directed and namelist I/O on internal files, binary, octal, and hex constants, `O' and `Z' edit descriptors, NAMELIST, OPEN specifiers STATUS='REPLACE', the FILE= specifier may be omitted in an OPEN statement if STATUS='SCRATCH' is supplied, relational operators <, <=, , /=, > and >= may be used instead of .LT., .LE., .EQ., .NE., .GT. and .GE. respectively, SELECT CASE (but not for character types).
9. Separate Compilation of Subprograms
   Your main program is recognized by the program statement, as in the Convert program above. The subprograms (functions and subroutines) can be included in the same file as the main program (in which case you can compile everything in one shot) or can be stored in separate file(s). It is recommended that you store general reusable subprograms in separate files so that you can reuse them (without recompiling them) in future projects. To compile a file that contains only subprograms (no program statement), use the f2lib command, which generates object files, one per sub, in the mine directory, e.g. will compile (without linking) the subprogram in util.for and store the output (an object file) in the file util.o. f2lib is just a batch file that invokes the g77 command with the -c (compile-only) switch, viz.A program that uses pre-compiled object files can be compiled (and linked to them) by simply referring to them in the compilation command: The above command searches all object files in mine to resolve any missing reference in prog.for.
10. Separate Compilation of Subprograms, automated
    The supplied f2exe and f2lib batch files take care of separate compilation and delayed linking with object files and with the SLATEC subprograms. You don't have to directly issue the g77 command unless you use the old columnar style or you want to change one of the switches or directories.
11. Assembly Listing
    The -S (capital S) switch allows you to see a listing of the generated assembly code.

F@Y/HR/S03URL