Preprocessor Macros

This file describes macros that have effect on SYCL compiler and run-time.

• RESTRICT_WRITE_ACCESS_TO_CONSTANT_PTR

  The spec assumes that the SYCL implementation does address space deduction. However, for our implementation, the deduction is performed in the middle end, where it’s hard to provide user friendly diagnositcs. Due to these problems writing to raw pointers obtained from constant_ptr is not diagnosed now. The user can enable diagnostics upon writing to such pointers via enabling the RESTRICT_WRITE_ACCESS_TO_CONSTANT_PTR macro. This allows constant_ptr to use constant pointers as underlying pointer types. Thus, conversions from constant_ptr to raw pointers will return constant pointers and writing to const pointers will be diagnosed by the front-end. This behavior is not following the SYCL spec since constant_ptr conversions to the underlying pointer types return pointers without any additional qualifiers so it’s disabled by default.

• SYCL2020_DISABLE_DEPRECATION_WARNINGS

  Disables warnings coming from usage of SYCL 1.2.1 APIs, that are deprecated in SYCL 2020.

• SYCL_DISABLE_DEPRECATION_WARNINGS

  Disables all deprecation warnings in SYCL runtime headers, including SYCL 1.2.1 deprecations.

• SYCL_DISABLE_IMAGE_ASPECT_WARNING

  Disables warning diagnostic issued when calling device::has(aspect::image) and platform::has(aspect::image).

• SYCL_FALLBACK_ASSERT

  Defining as non-zero enables the fallback assert feature even on devices without native support. Be aware that this will add some overhead that is associated with submitting kernels that call assert(). When this macro is defined as 0 or is not defined, the logic for detecting assertion failures in kernels is disabled, so a failed assert will not cause a message to be printed and will not cause the program to abort. Some devices have native support for assertions. The logic for detecting assertion failures is always enabled on these devices regardless of whether this macro is defined because that logic does not add any extra overhead. One can check to see if a device has native support for assert() via aspect::ext_oneapi_native_assert. This macro is undefined by default.

• SYCL2020_CONFORMANT_APIS (deprecated) This macro is used to comply with the SYCL 2020 specification, as some of the current implementations may be widespread and not conform to it. Defining this macro currently has no effect on the API. This preprocessor macro has been deprecated in favor of the -fpreview-breaking-changes compiler option.

Version macros

• __LIBSYCL_MAJOR_VERSION is set to SYCL runtime library major version.

• __LIBSYCL_MINOR_VERSION is set to SYCL runtime library minor version.

• __LIBSYCL_PATCH_VERSION is set to SYCL runtime library patch version.