Open Radar

 
Summary:
The generic function defined with curried function notation doesn’t capture the first parameter and appears to use some uninitialized(?) value, when invoked with arguments of type Double.

Steps to Reproduce:
Execute in playground or REPL: 

func curry<A, B, Z>(f: (A, B) -> Z)(_ a: A)(_ b: B) -> Z {
    println("a:\(a) b:\(b)")
    return f(a, b)
}

func quadratic(c: Double, z: Double) -> Double { return z * z + c }

quadratic(1, 2)

let q = curry(quadratic)
q(a: 1)(b: 2) // Should be 5!

let qc = q(a: 1)
qc(b: 2)  // Should be 5!

curry(quadratic)(a: 1)(b: 2) // correct

Expected Results:
Console output should be
a:1.0 b:2.0
a:1.0 b:2.0
a:1.0 b:2.0

Actual Results:
a:6.95075740882923e-310 b:2.0
a:6.95075741238967e-310 b:2.0
a:1.0 b:2.0

Version:
Version 6.2 (6C101) Beta 3

Notes:
Specialized definition of the curry function works correctly:

func curry(f: (Double, Double) -> Double)(_ a: Double)(_ b: Double) -> Double {
    println("a:\(a) b:\(b)")
    return f(a, b)
}