Anastasia added a comment. Just to move the discussion from https://reviews.llvm.org/D101519 here. First of all I think this change should not be OpenCL specific i.e. there is not reason to do something different from C++ in general.
Embedded C doesn't regulate the conversions between non-pointer types with different address spaces but in OpenCL C we have allowed them apparently https://godbolt.org/z/9f75zxj7v. I am not sure whether this was done intentionally or not. However, in C there are no references and other features that might create problems. At the same time it seems C++ allows casting away const https://godbolt.org/z/fo3axbq3e But it contradicts the comment in the code: > // C++ 5.2.10p2 has a note that mentions that, subject to all other > // restrictions, a cast to the same type is allowed so long as it does not > // cast away constness. In C++98, the intent was not entirely clear here, > // since all other paragraphs explicitly forbid casts to the same type. > // C++11 clarifies this case with p2. I would like to see if @rjmccall has any opinion on whether reinterpreting between non-pointer types with different address spaces is reasonable? In general it makes sense to follow logic for other type qualifier here but I was thinking of whether we can allow something weird to be written by relaxing this for address spaces local int i; const global int & ii = reinterpret_cast<global int>(i); I think this code is completely meaningless as it requires creating a temporary in global address space? I am not sure what we will even emit in IR? Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D102689/new/ https://reviews.llvm.org/D102689 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
