fix called-argument analysis for calls with splat

[JeffBezanson]

No description provided.

[mlechu]

julia> function sprint2(f::Function, args...)
           s = IOBuffer()
           f(s, args...)
           String(Base._unsafe_take!(s))
       end
sprint2 (generic function with 1 method)

julia> sprint2(Base.showerror, MethodError("hi", (Int,)))
""

inference bug? nevermind...

julia> function sprint2(f::Function, args...)
           s = IOBuffer()
           f(s, args...); sleep(1)
           String(Base._unsafe_take!(s))
       end
sprint2 (generic function with 1 method)

julia> sprint2(Base.showerror, MethodError("hi", (Int,)))
"MethodError: objects of type String are not callable.\nIn case you did not try calling it explicitly, check if a String has been passed as an argument to a method that expects a callable instead.\nThis error has been manually thrown, explicitly, so the method may exist but be intentionally marked as unimplemented."

[vtjnash]

It is an llvm bug (or rather, our bug in what we codegen for llvm). I'm looking into why we did what we did