@preconcurrency attribute on conformance to empty-but-not-really protocol has no effect

[an0]

Description

See details here:
https://forums.swift.org/t/preconcurrency-attribute-on-conformance-to-aprotocol-has-no-effect/75313

Reproduction

See details here:
https://forums.swift.org/t/preconcurrency-attribute-on-conformance-to-aprotocol-has-no-effect/75313

Expected behavior

When a protocol inherits from other non-empty protocols it should be treated as non-empty protocol and compiler should allow @preconcurrency attribute on its conformance.

Environment

swift-driver version: 1.115.1 Apple Swift version 6.0.3 (swiftlang-6.0.3.1.10 clang-1600.0.30.1)

Additional information

No response