The options that enable the compiler to process a source program in a beneficial way for or required by the application, can be divided in two groups described in the two sections below. See a summary of these options.
DO loops
The -onetrip option directs the compiler to compile DO loops at least once. By default Fortran DO loops are not performed at all if the upper limit is smaller than the lower limit. The option -1 has the same effect. This supports old programs from the Fortran–66 standard, when all DO loops executed at least once.
Fixed Format Source
The -FI option specifies that all the source code is in fixed format; this is the default except for files ending with the extension.f, .for, .ftn.
-132 permits fixed form source lines to contain up to 132 characters. The -extend_source, option has the same effect as -132.
Free Format Source
-FR options Specifies that all the source code is in Fortran free format; this is the default for files ending with the suffix .f90.
Character Definitions
The -pad_source option enforces the acknowledgment of blanks at the end of a line.
The -us option appends an underscore to external subroutine names. -nus disables appending an underscore to an external subroutine name.
The -nus[file] option directs to not append an underscore to subroutine names listed in file. Useful when linking with C routines.
The -nbs option directs the compiler to treat backslash (\) as a normal graphic character, not an escape character. This may be necessary when transferring programs from non-UNIX environments, for example from VAX-VMS. See Escape Characters.
This group discusses options that enable compatibility with other compilers.
Cross-platform
The -ansi[-] enables (default) or disables assumption of the program’s ANSI conformance. Provides cross-platform compatibility. This option is used to make assumptions about out-of-bound array references and pointer references.
DEC*, VMS
The -dps, option enables (default) or disables DEC* parameter statement recognition.
The -vms option enables support for extensions to Fortran that were introduced by Digital VMS Fortran compilers. The extensions are as follows:
The compiler permits shortened, apostrophe-separated syntax for parameters in I/O statements. For example, a statement of the form: WRITE(4'7) FOO is permitted and is equivalent to WRITE(UNIT=4, REC= 7) FOO.
The compiler assumes that the value specified for RECL in an OPEN statement is given in words rather than bytes. This option also implies -dps, though -dps is on by default.
C Language
The -lowercase maps external routine names and symbol names (linker) to lowercase alphabetic characters. This option is useful when mixing Fortran with C programs.
The -uppercase maps external names to uppercase alphabetic characters.
Note
Do not use the -uppercase option in combination
with -Vaxlib or -posixlib.
For compatibility with C usage, the backslash (\) is normally used in Intel® Fortran Compiler as an escape character. It denotes that the following character in the string has a significance which is not normally associated with the character. The effect is to ignore the backslash character, and either substitute an alternative value for the following character or to interpret the character as a quoted value.
The escape characters recognized, and their effects, are described in the table below. Thus, 'ISN\'T' is a valid string. The backslash (\) is not counted in the length of the string.
Escape Characters and Their Effect
Escape Character |
Effect |
|
\n |
new line |
|
\t |
horizontal tab |
|
\v |
vertical tab |
|
\b |
backspace |
|
\f |
form feed |
|
\0 |
null |
|
\' |
apostrophe (does not terminate a string) |
|
\" |
double quote (does not terminate a string) |
|
\\ |
\ (a single backslash) |
|
\x |
x, where x is any other character |
This information is useful for recent Linux users after working with Windows. The line terminators are different between Linux and Windows. On Windows, line terminators are \r\n while on Linux they are just \n. Typically, a file transfer program will take care of this issue for you if you transfer the file in text mode. If the file is transferred in binary mode (but the file is really text file), the problem will not be resolved by FTP.