[clang] [Clang][HIP] Suppress availability diagnostics for mismatched host/device overloads (PR #93546)

[Artem Belevich via cfe-commits]

Artem-B wrote:

> Therefore, the following code would cause a deprecation warning during host compilation, even though val is only used as part of a device function:

This is where we may need help from @zygoloid.

> __attribute__((device)) std::enable_if<(val() > 0), int>::type fun(void)

Here `val()` is evaluated in global context as it does not have a caller function. As such, overload resolution picking a host function during host compilation is a WAI, even if it happens to be part of a GPU-side function declaration.

In this case, function overload fails, and the patch tries to suppress such an error.

If we are adding a special case for handling overloads, perhaps a better approach would be to consider inferring the caller context from the enveloping function declaration attributes, and allow overload resolution to pick a device function instead. It would avoid the errors you're trying to suppress, and it will arguably make things more consistent -- the function declaration will have the same signature in both host and device compilations.

@zygoloid -- do you think such a change will create other issues?




https://github.com/llvm/llvm-project/pull/93546