Compatibility Options

The compatibility options let you specify how to make your source files and data files compatible with older Fortran versions or other operating systems, such as big endian unformatted data files, OpenVMS* systems run-time behavior, and Microsoft* Fortran PowerStation.

See Also

Data Options

Language Options

Descriptions of Compatibility Options

-1

Default: Off

Alternate syntax: -onetrip

Specifies that the compiler should execute DO loops at least once. See also -[no]f66.

-assume [no]bscc

Default: -assume nobscc

Alternate syntax: -nbs is the same as -assume bscc

Tells the compiler to treat the backslash character (\) as a C-style control (escape) character in character literals. The default, -assume nobscc ("assume no BackSlashControlCharacters"), tells the compiler to treat the backslash character as a normal character instead of a control character in character literals.

This option is useful when transferring programs from non-UNIX* environments, such as OpenVMS*.

-convert

Default: None.

Specifies the format of unformatted files containing numeric data. Possible values are:

• -convert big_endian

• -convert cray

• -convert ibm

• -convert little_endian

• -convert native

• -convert vaxg

• -convert vaxd

See Supported Native and Nonnative Numeric Formats.

-[no]f77rtl

Default: -nof77rtl

Specifies the use of FORTRAN 77 run-time behavior. If you use the default value (-nof77rtl), Intel Fortran run-time behavior is used.

Specifying this option controls control the following run-time behavior:

• When the unit is not connected to a file, some INQUIRE specifiers will return different values:
  NUMBER returns 0
  ACCESS returns 'UNKNOWN'
  BLANK returns 'UNKNOWN'
  FORM returns 'UNKNOWN'

• List-directed input for character strings must be delimited by apostrophes or quotation marks, or an error will result.

• When processing NAMELIST input:
  Column 1 of each record is skipped
  The '$' or '&' that appears prior to the group-name must appear in column 2 of the input record

-fpscomp all and -fpscomp none

Default: -fpscomp libs

Specifies that all the -fpscomp options for compatibility with Microsoft* Fortran PowerStation should be used. The default value specifies that the PowerStation portability library should be passed to the linker.

-fpscomp none specifies that no options for Fortran PowerStation compatibility should be used.

-fpscomp [no]filesfromcmd

Default: -fpscomp nofilesfromcmd

Specifies Microsoft* Fortran PowerStation behavior when the OPEN statement file specifier is blank. This option looks in the command-line arguments for unspecified filenames on an OPEN(. . . FILE=' ', . . .) and prompts for filenames at the terminal console.

-fpscomp [no]general

Default: -fpscomp nogeneral

Specifies that Microsoft* Fortran PowerStation semantics should be used where differences exist between Intel Fortran and PowerStation.

-fpscomp [no]ioformat

Default: -fpscomp noioformat

Specifies Microsoft* Fortran PowerStation semantic conventions and record formats for list-directed formatted I/O and unformatted I/O.

-fpscomp [no]libs

Default: -fpscomp libs

Specifies that the PowerStation portability library should be passed to the linker.

-fpscomp [no]logicals

Default: -fpscomp nologicals

Specifies that Microsoft* Fortran PowerStation representation of LOGICAL values will be used.

-prof_format_32

Default: Off

Produces profile data with 32-bit counters. The default is to produce profile data with 64-bit counters to handle large numbers of events.

This option allows compatibility with earlier compilers.

-vms

Default: Off

Causes the run-time system to behave like HP Fortran on OpenVMS Alpha systems and VAX* systems (VAX FORTRAN*) in the following ways:

• Certain defaults
  In the absence of other options, -vms sets the defaults as -check format and -check output_conversion.

• Alignment
  The -vms option does not affect the alignment of fields in records or items in common blocks. Use -align norecords to pack fields of records on the next byte boundary for compatibility with HP Fortran on OpenVMS systems.

• Carriage control default
  If -vms -ccdefault default is specified, carriage control defaults to FORTRAN if the file is formatted and the unit is connected to a terminal.

• INCLUDE qualifiers
  /LIST and /NOLIST are recognized at the end of the file name in an INCLUDE statement at compile time.
  If the file name in the INCLUDE statement does not specify the complete path, the path used is the current directory.
  Note that if -vms is not specified, the path used is the directory where the file that contains the INCLUDE statement resides.

• Quotation mark character
  A quotation mark (") character is recognized as starting an octal constant ("0..7) instead of a character literal ("...").

• Deleted records in relative files
  When a record in a relative file is deleted, the first byte of that record is set to a known character (currently ' @ ' ). Attempts to read that record later result in ATTACCNON errors. The rest of the record (the whole record, if -vms is not specified) is set to nulls for unformatted files and spaces for formatted files.

• ENDFILE records
  When an ENDFILE is performed on a sequential unit, an actual 1-byte record containing a Ctrl/Z is written to the file. If -vms is not specified, an internal ENDFILE flag is set and the file is truncated.
  The -vms option does not affect ENDFILE on relative files: these files are truncated.

• Implied logical unit numbers
  The -vms option enables Intel Fortran to recognize certain environment variables at run time for ACCEPT, PRINT, and TYPE statements and for READ and WRITE statements that do not specify a unit number (such as READ (*,1000)).

• Treatment of blanks in input
  The -vms option causes the defaults for the keyword BLANK in OPEN statements to become ' NULL ' for an explicit OPEN and ' ZERO ' for an implicit OPEN of an external or internal file. For more information, see the description of the OPEN statement.

• OPEN statement effects
  Carriage control defaults to FORTRAN if the file is formatted, and the unit is connected to a terminal (checked by means of isatty(3) ). Otherwise, carriage control defaults to LIST.
  The -vms option affects the record length for direct access and relative organization files. The buffer size is increased by 1 to accommodate the deleted record character.

• Reading deleted records and ENDFILE records
  The run-time direct access READ routine checks the first byte of the retrieved record. If this byte is ' @ ' or NULL ("\0"), then an ATTACCNON error is returned.
  The run-time sequential access READ routine checks to see if the record it just read is one byte long and contains a Ctrl/Z. If this is true, it returns EOF.