Executable target depending on executable product backed by a binary target fails to build

[FranzBusch]

Is it reproducible with SwiftPM command-line tools: swift build, swift test, swift package etc?

• Confirmed reproduction steps with SwiftPM CLI. The description text must include reproduction steps with either of command-line SwiftPM commands, swift build, swift test, swift package etc.

Description

Related to: apple/swift-protobuf#1854 (comment)

A package with the following setup

import PackageDescription

let package = Package(
    name: "swift-proto-repro",
    products: [
        .executable(
            name: "repro",
            targets: ["repro"]),
    ],
    dependencies: [
        .package(url: "https://github.com/apple/swift-protobuf", from: "1.31.1"),
    ],
    targets: [
        .executableTarget(
            name: "repro",
            dependencies: [
                .product(name: "protoc", package: "swift-protobuf"),
            ]
        ),
    ],
)

Fails to build running swift build with the following error

error: InternalError(description: "Internal error. Please file a bug at https://github.com/swiftlang/swift-package-manager/issues with this info. No description for product: <ResolvedProduct: protoc, executable>")

Expected behavior

No response

Actual behavior

No response

Steps to reproduce

No response

Swift Package Manager version/commit hash

No response

Swift & OS version (output of swift --version ; uname -a)

No response

[dschaefer2]

Yes, this is an unsupported operation. When executable targets depend on other executable target, SwiftPM takes the modules from the first and links them into the executable in the second. You can't do that with binary targets since we have no idea how they were built.

We should be producing a proper error message here.