Ubuntu developer snapshot requires Foundation for print statement

Using Swift
,
1

I downloaded the latest developer snapshot (swift-DEVELOPMENT-SNAPSHOT-2018-05-26-a-ubuntu16.04.tar.gz) from Swift.org - Download Swift, verified the signature and extracted the archive. Then

# cd swift-DEVELOPMENT-SNAPSHOT-2018-05-26-a-ubuntu16.04
# usr/bin/swift
Welcome to Swift version 4.2-dev (LLVM 5913b477db, Clang 8c9b467e0e, Swift ec5b51ec7c). Type :help for assistance.
 1> print(1)
error: Couldn't lookup symbols:
 type metadata for Swift.Int
 Swift.print(_: Any..., separator: Swift.String, terminator: Swift.String) -> ()
 Swift._allocateUninitializedArray<A>(Builtin.Word) -> (Swift.Array<A>, Builtin.RawPointer)
 swift_bridgeObjectRelease
 default argument 1 of Swift.print(_: Any..., separator: Swift.String, terminator: Swift.String) -> ()
 default argument 2 of Swift.print(_: Any..., separator: Swift.String, terminator: Swift.String) -> ()
 swift_release
 type metadata for Any
 swift_retain

 1>

Importing Foundation first seems to solve the problem:

# cd swift-DEVELOPMENT-SNAPSHOT-2018-05-26-a-ubuntu16.04
# usr/bin/swift
Welcome to Swift version 4.2-dev (LLVM 5913b477db, Clang 8c9b467e0e, Swift ec5b51ec7c). Type :help for assistance.
  1> import Foundation
  2> print(1)
1
  3>

With swift-4.1.1-RELEASE-ubuntu16.04.tar.gz I can use print() without importing Foundation first:

# cd swift-4.1.1-RELEASE-ubuntu16.04
# usr/bin/swift
Welcome to Swift version 4.1.1 (swift-4.1.1-RELEASE). Type :help for assistance.
  1> print(1)
1
  2>

This looks like a bug to me. Or am I doing something wrong?

(All tests were done on Ubuntu 16.04, running under VirtualBox.)

2

The missing symbols all come from the standard library and runtime. Out of curiosity, what happens if you import Swift first? It may be failing to load anything implicitly.

3

import Swift does not help:

$ cd swift-DEVELOPMENT-SNAPSHOT-2018-05-26-a-ubuntu16.04/
$ usr/bin/swift
Welcome to Swift version 4.2-dev (LLVM 5913b477db, Clang 8c9b467e0e, Swift ec5b51ec7c). Type :help for assistance.
  1>  
  2> import Swift
  3>  
  4> print(1)
error: Couldn't lookup symbols:
  type metadata for Swift.Int
  Swift.print(_: Any..., separator: Swift.String, terminator: Swift.String) -> ()
  Swift._allocateUninitializedArray<A>(Builtin.Word) -> (Swift.Array<A>, Builtin.RawPointer)
  swift_bridgeObjectRelease
  default argument 1 of Swift.print(_: Any..., separator: Swift.String, terminator: Swift.String) -> ()
  default argument 2 of Swift.print(_: Any..., separator: Swift.String, terminator: Swift.String) -> ()
  swift_release
  type metadata for Any
  swift_retain

  4>  
  5> import Foundation
  6> print(1)
1
  7>

Another example:

$ usr/bin/swift
Welcome to Swift version 4.2-dev (LLVM 5913b477db, Clang 8c9b467e0e, Swift ec5b51ec7c). Type :help for assistance.
  1> import Swift 
  2> let a = min(1.0, 2.0)
a: Double = <extracting data from value failed>

error: Couldn't lookup symbols:
  protocol witness table for Swift.Double : Swift.Comparable in Swift
  type metadata for Swift.Double
  Swift.min<A where A: Swift.Comparable>(A, A) -> A

  2>  
  3> import Foundation
  4> let a = min(1.0, 2.0) 
a: Double = 1
  5>
4

The problem still exists in the May 29, 2018 snapshot. I filed a bug report:

5

Interestingly, it seems like all of the Swift 4.2 snapshots have this issue. I tried ones going back until May 8th and I still saw this occur.

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