Overview: Parallel Programming

For parallel programming, the Intel® C++ Compiler supports both the OpenMP* 2.0 API and an automatic parallelization capability. The following table lists the options that perform OpenMP and auto-parallelization support.

Option Description
-openmp Enables the parallelizer to generate multithreaded code based on the OpenMP directives. Default: OFF.
-openmp_report{0|1|2} Controls the OpenMP parallelizer's diagnostic levels. Default: -openmp_report1.
-openmp_stubs Enables compilation of OpenMP programs in sequential mode. The OpenMP directives are ignored and a stub OpenMP library is linked. Default: OFF.
-parallel Enables the auto-parallelizer to generate multithreaded code for loops that can be safely executed in parallel. Default: OFF.
-par_threshold{n} Sets a threshold for the auto-parallelization of loops based on the probability of profitable execution of the loop in parallel, n=0 to 100. n=0 implies "always." Default: n=100.
-par_report{0|1|2|3} Controls the auto-parallelizer's diagnostic levels.
Default: -par_report1


When both -openmp and -parallel are specified on the command line,  the -parallel option is honored only in routines that do not contain OpenMP directives. For routines that contain OpenMP directives, only the -openmp option is honored.