Inline asm: *const [type error] does not implement the Copy trait

[Kyuuhachi]

Code

fn main() {
	let peb: *const PEB;
	unsafe { std::arch::asm!("mov {0}, fs:[0x30]", out(reg) peb); }
}

Current output

error[E0412]: cannot find type `PEB` in this scope
 --> src/main.rs:2:18
  |
2 |     let peb: *const PEB;
  |                     ^^^ not found in this scope

error: arguments for inline assembly must be copyable
 --> src/main.rs:3:49
  |
3 |     std::arch::asm!("mov {0}, fs:[0x30]", out(reg) peb);
  |                                                    ^^^
  |
  = note: `*const [type error]` does not implement the Copy trait

For more information about this error, try `rustc --explain E0412`.

Desired output

Probably just omit the second error; no `Copy` error is given when moving an unknown type normally.

Rationale and extra context

No response

Other cases

No response

Anything else?

Happens on 1.73.0-nightly (2023-07-16 0e8e857b11f60a785aea), as well as several earlier versions.

[compiler-errors]

Just needs someone to suppress this error if the type references_error, I think.

[RickleAndMortimer]

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[RickleAndMortimer]

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[ameya-deshmukh]

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[Rajveer100]

@Kyuuhachi @compiler-errors
Hi! I have given a brief introduction of myself in the new members zulip channel.

With that said, I have potentially setup the necessary pre-requisites and compiler infrastructure in my local machine, also re confirmed by using the ./x check and other build commands which seem to work. As per the docs, I have the all the toolchains command executed (for stages [0-2]).

Like any other contribution, I figured that in rust-lang repo, good-first-issues are tagged as E-Easy for new-comers, and to start, I have chosen this issue.

Until now, I have found the following snippet which I presume is targeting the output:

// Check that the type implements Copy. The only case where this can
// possibly fail is for SIMD types which don't #[derive(Copy)].
if !ty.is_copy_modulo_regions(self.tcx, self.param_env) {
    let msg = "arguments for inline assembly must be copyable";
    let mut err = self.tcx.sess.struct_span_err(expr.span, msg);
    err.note(format!("`{ty}` does not implement the Copy trait"));
    err.emit();
}

Would be great if one could point out any points I may have missed out!
A head start would be great!

[RickleAndMortimer]

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