Radar #?

Bug.txt

Here's some sample code that works fine in Xcode 10.1, but fails to compile in 10.2 even though it's valid code.

The #if/#else/#endif code seems to be confusing the compiler and thus it is mixing up scope.

Xcode Version 10.2 (10E125) -> Broken
Xcode Version 10.1 (10B61) -> Works correctly

sample.swift

// This variable uses #if to create two possible code paths, in this example, it's just using `true`, but
// in my real project it uses a variable defined in the Scheme. The result is the same.
// The error here is that Xcode is disallowing the use of the variable name `firstVar` inside the braces
// which is perfectly valid code. You can see it work correctly below in `secondVar`.
let firstVar: String = {
    #if true
        let firstVar: String = "One"
    #else
        let firstVar: String = "Two"
    #endif
    return firstVar // Variable used within its own initial value
}()

// This variable breaks down to the exact same code, but without the #if and it works correctly.
let secondVar: String = {
    let secondVar: String = "Three"
    return secondVar // Essentially the same code, but with no error
}()