[PATCH] D78655: [CUDA][HIP] Let non-caputuring lambda be host device

[Paul Fultz II via Phabricator via cfe-commits]

pfultz2 added a comment.

> Could you give an example to demonstrate current use and how it will break?

Here is place where it would break:

https://github.com/ROCmSoftwarePlatform/AMDMIGraphX/blob/develop/src/targets/gpu/device/include/migraphx/gpu/device/multi_index.hpp#L129

This change was already included in a fork of llvm in rocm 3.5 and 3.6 releases which is why this compiles. This also compiles using the hcc-based hip compilers which is what previous rocm versions used. It would be best if this can be upstreamed, so we dont have to hold on to these extra changes in a fork.

Part of the motivation for this change was that it wasn't always clear in code where the `__device__` attribute is needed with lambdas sometimes. It also makes it more consistent with `constexpr` lambdas and hcc-based hip compiler. Including this for capturing lambdas will make this simpler and easier to understand.

If there are concerns about making it default for capturing lambdas, then can we at least just have a flag to enable this for capturing lambdas?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D78655/new/

https://reviews.llvm.org/D78655