[SR-8321] 4.2 regression with inout-to-pointer case expressions

[hamishknight]

Previous ID	SR-8321
Radar	None
Original Reporter	@hamishknight
Type	Bug
Status	Closed
Resolution	Invalid

Environment

Apple Swift version 4.1.2 (swiftlang-902.0.54 clang-902.0.39.2)
Target: x86_64-apple-darwin17.6.0

Apple Swift version 4.2-dev (LLVM da1c9a3ae4, Clang a0e59b03e6, Swift e325e32)
Target: x86_64-apple-darwin17.6.0

Additional Detail from JIRA

Votes	0
Component/s	Compiler
Labels	Bug, 4.2Regression, TypeChecker
Assignee	None
Priority	Medium

md5: 2fec481b892614e8c266431c0c02b81a

Issue Description:

The following compiles in Swift 4.1 and on master, but doesn't compile in the latest 4.2 snapshot:

var x = 0
func foo(_ ptr: UnsafeMutableRawPointer) {
  switch ptr {
  case &x: // error in 4.2: Use of extraneous '&'
    break
  default:
    break
  }
}

[hamishknight]

Huh, weird it's now working in the latest 4.2 snaphot.... never mind then!