Compiler crash when pointers to generics from template

[lucian]

I have stumbled this error: "nim c main" gives "SIGSEGV: Illegal storage 
access. (Attempt to read from nil?)" on machine setup: Nim Compiler Version 
0.18.0 [Windows: amd64], "uname -a" -> MINGW64_NT-10.0 <name> 2.9.0(0.318/5/3) 
2017-09-13 23:16 x86_64 Msys

Simple sources are as:
    
    
    # lib1.nim
    proc PresentModeA*[T:string|seq[byte]](d: T) =
        echo "A Presenting: ", $d[0]
    
    
    
    #lib2.nim
    
    proc PresentModeB*[T:string|seq[byte]](d: T) =
        echo "B Presenting: ", $d[0]
    
    
    
    #main app
    import
        os, sequtils, strutils,
        lib1, lib2
    
    type
        modes = enum
            typeA, tyepB
    var
        mode = typeA
    
    template PresentGeneric(s: typed) =
        var dispatcher = @[PresentModeA, PresentModeB]
        dispatcher[mode.ord](s)
    
    proc main() =
        # 'mode' is really dependant on optargs
        
        let data = @[0x00.byte, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07]
        PresentGeneric(data)
        
        let text = "Something to shout about."
        PresentGeneric(text)
    
    main()
    

Is this design supported or should avoid generics pointers?

Thank you.