fix https://github.com/fsharp/fsharp/issues/555 (#2950)
fix https://github.com/fsharp/fsharp/issues/555 (#2950)


brettfo/visualfsharp,brettfo/visualfsharp,fsharp/fsharp,syeerzy/visualfsharp,syeerzy/visualfsharp,fsharp/fsharp,dsyme/FSharp.Compiler.Service,ncave/FSharp.Compiler.Service,fsharp/fsharp,brettfo/visualfsharp,dsyme/fsharp,dsyme/FSharp.Compiler.Service,dsyme/FSharp.Compiler.Service,dsyme/fsharp,dsyme/fsharp,ncave/FSharp.Compiler.Service,brettfo/visualfsharp,Jand42/FSharp.Compiler.Service,ncave/FSharp.Compiler.Service,dsyme/fsharp,brettfo/visualfsharp,syeerzy/visualfsharp,Jand42/FSharp.Compiler.Service,syeerzy/visualfsharp,dsyme/fsharp,cloudRoutine/FSharp.Compiler.Service,dsyme/fsharp,sergey-tihon/FSharp.Compiler.Service,sergey-tihon/FSharp.Compiler.Service,brettfo/visualfsharp,dsyme/fsharp,cloudRoutine/FSharp.Compiler.Service,Jand42/FSharp.Compiler.Service,syeerzy/visualfsharp,sergey-tihon/FSharp.Compiler.Service,syeerzy/visualfsharp,cloudRoutine/FSharp.Compiler.Service