Developer Guide and Reference

Contents

qopenmp, Qopenmp

Enables the parallelizer to generate multi-threaded code based on OpenMP* directives.

Syntax

Linux and macOS:
-qopenmp
-qno-openmp
Windows:
/Qopenmp
/Qopenmp-
Arguments
None
Default
-qno-openmp
or
/Qopenmp-
No OpenMP* multi-threaded code is generated by the compiler.
Description
This option enables the parallelizer to generate multi-threaded code based on OpenMP* directives. The code can be executed in parallel on both uniprocessor and multiprocessor systems.
This option works with any optimization level. Specifying no optimization (
-O0
on Linux* or
/Od
on Windows*) helps to debug OpenMP applications.
On
macOS*
systems, when you enable OpenMP* API, you must also set the DYLD_LIBRARY_PATH environment variable within Xcode* or an error will be displayed.
Options that use OpenMP* API are available for both Intel® microprocessors and non-Intel microprocessors, but these options may perform additional optimizations on Intel® microprocessors than they perform on non-Intel microprocessors. The list of major, user-visible OpenMP constructs and features that may perform differently on Intel® microprocessors versus non-Intel microprocessors include: locks (internal and user visible), the SINGLE construct, barriers (explicit and implicit), parallel loop scheduling, reductions, memory allocation, thread affinity, and binding.
Optimization Notice
Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.
Notice revision #20110804
Alternate Options
Linux
and
macOS*
:
-fopenmp
Windows:
/openmp

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804