OMP_DEFAULT_DEVICE (GNU libgomp)

### 4.6 `OMP_DEFAULT_DEVICE` – Set the device used in target regions ¶

ICV: default-device-var
Scope: data environment
Description:

  Set to choose the device which is used in a `target` region, unless the value is overridden by `omp_set_default_device` or by a `device` clause. The value shall be the nonnegative device number. If no device with the given device number exists, the code is executed on the host. If unset, `OMP_TARGET_OFFLOAD` is `mandatory` and no non-host devices are available, it is set to `omp_invalid_device`. Otherwise, if unset, device number 0 is used.

See also:

  `omp_get_default_device` – Get the default device for target regions, `omp_set_default_device` – Set the default device for target regions, `OMP_TARGET_OFFLOAD` – Controls offloading behavior

Reference:

  OpenMP specification v5.2, Section 21.2.7