Value-initialize marray to avoid undefined behavior. #1161
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sycl::marray default constructor check has undefined behavior. marray is default-initialized, which means that elements of marray is also default-initialized. For element data type like `int` default-initialized value with automatic storage produces indeterminate value. The check compares marray elements with value-initialized object (i.e. with `0` for `int` data type). Using indetermiate values in compare operation causes undefined behavior. The issue is exposed by recent change in DPC++ implementation, which switched marray elements initialization in default constructor from value-initialization to default-initialization. intel/llvm@ba4f090 See https://en.cppreference.com/w/cpp/language/default_initialization.html for more details.
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sycl::marray default constructor check has undefined behavior.
marray is default-initialized, which means that elements of marray is
also default-initialized. For element data type like
intdefault-initialized value with automatic storage produces indeterminate
value. The check compares marray elements with value-initialized object
(i.e. with
0forintdata type). Using indetermiate values incompare operation causes undefined behavior.
The issue is exposed by recent change in DPC++ implementation, which
switched marray elements initialization in default constructor from
value-initialization to default-initialization.
intel/llvm@ba4f090
See
https://en.cppreference.com/w/cpp/language/default_initialization.html
for more details.