A compiler option (also known as a switch) is an optional string of one or more alphanumeric characters preceded by a dash (-). Options to the ifort command affect how the compiler processes a file in conjunction with the file name suffix. The simplest form of the ifort command is often sufficient.
Some options are on by default when you invoke the compiler.
For help, enter -help on the command line, which displays brief information about all the command-line options.
The Compiler Options reference provides a complete description of each compiler option.
Note
If there are enabling and disabling versions of options on the command line, or two versions of the same option, the last one takes precedence.
If you compile parts of your program by using multiple ifort commands, options that affect the execution of the program should be used consistently for all compilations, especially if data is shared or passed between procedures. For example:
The same data alignment needs to be used for data passed or shared by module definition (such as user-defined structures) or common block. Use the same version of the -align option for all compilations.
The program might contain INTEGER, LOGICAL, REAL, COMPLEX, or DOUBLE PRECISION declarations without a kind parameter or size specifier that is passed or shared by module definition or common block. You must consistently use the options that control the size of such numeric data declarations.
You can override some options specified on the command line by using the OPTIONS statement in your Fortran source program. The options specified by the OPTIONS statement affect only the program unit where the statement occurs.