This topic is written for developers who are familiar with Intel Fortran Version 7.1 or earlier versions are now using Intel Fortran Version 8.0 and later releases.
Intel® Fortran supports extensions to the ISO and ANSI standards, including a number of extensions defined by:
Intel Fortran for various platforms
Microsoft* Fortran PowerStation 4.0
Many language extensions associated with Microsoft* Fortran PowerStation Version 4 have been added to Intel Fortran.
Some differences are:
The command name for command-line use is now ifort. Earlier versions of Intel Fortran used a command name of ifc or efc. For Intel Fortran, these command names will still be accepted, but in some future Intel Fortran release, only the ifort command name will be accepted.
The default configuration file name is now ifort.cfg instead of ifc.cfg or efc.cfg.
The predefined symbol name for the Intel Fortran compiler is __INTEL_COMPILER and it has a value of 800 for Intel Fortran Version 8.0, 810 for Intel Fortran Version 8.1 and 900 for Intel Fortran Version 9.0.
The record length (RECL specifier) for unformatted files is now 32-bit words. To get the record length in bytes, use the -assume byterecl option.
The backslash character (\) is not treated as an escape character for control sequences in character literals. To force the backslash to start escape sequences, use the -assume bscc option.
Intel Fortran Version 8.x
and later releases by default uses the integer -1 for the value
of .TRUE. whereas Version 7 uses the integer 1 for the value of .TRUE..
If you use the -fpscomp logicals option with Version
8.x and later releases, the compiler will use the integer 1 for the value
of .TRUE..
Version 8.x and later releases always use the integer 0 as the value
of .FALSE., as did Version 7.
User-written routines in Fortran or other languages (for example, C)
need to insure that they use values for .TRUE. and .FALSE. consistent
with the compiler's choice.
The random number generator used in Version 8.x
and later releases is different from the random number generator used
in Version 7.
Version 8 and later releases use the random number generator based
on the algorithm of Park and Miller, which is the generator used by Compaq
Fortran. Version 7 used the Marsaglia random number generator.
Both of these random number generators are compatible with the Fortran
90 standard.
In addition, Version 8.x and later releases use different algorithms
for the RANDOM_NUMBER and RANDOM_SEED intrinsics (compared to Version
7) and different algorithms are used for these intrinsics on IA32 and
Itanium-based systems.
Some documentation has been moved or changed. In particular:
The Intel® Fortran User’s Guide, Volumes I and II have been renamed to Building Applications and Optimizing Applications, respectively.
Intel Fortran language information previously described in the Intel Fortran Programmer’s Reference, including intrinsics procedures and directives, is now described in the online Language Reference.
All Intel Fortran language elements and library routines are described in this online help file, allowing easy lookup of reference information.
The following Intel Fortran Version 7.1 features are not available in Intel Fortran Version 8.x or later releases:
IMPLICIT AUTOMATIC | STATIC statements
The Intel Fortran run-time library system's ability to work with the Itanium® processor simulator