Tutorial: Debugging with Intel® Distribution for GDB*

Limitations

Explicit Template Instantiations

The compiler omits the code of the method of a template class if that method is not used in the code. This causes an issue when you want to invoke the omitted function. This is a C++ issue. This issue is seen in DPC++ because the basic classes (range, id, nd_range, accessor, and others) are templates, which have many overloaded operators. Examples:

As a solution to this, you can explicitly instantiate a template class in your source. Then the methods of the template instance are available in the binary. The instantiations can be surrounded with #ifndef NDEBUG and #endif to avoid code bloat in release builds. Example:

#ifndef NDEBUG

template class cl::sycl::id<1>;
template class cl::sycl::id<2>;
template class cl::sycl::id<3>;
template class cl::sycl::range<1>;
template class cl::sycl::nd_range<1>;

#endif // #ifndef NDEBUG

Accessor's Operator []

Elements of an accessor object cannot be accessed using the multi-dimensional access syntax during expression evaluation. See example below:

print anAccessor[5][3][4]
Example output:
Cannot resolve function operator[] to any overloaded instance

Instead, use an id object: