Can't build FFTW.jl

I’m having trouble building FFTW.jl

julia> Pkg.build("FFTW")
[ Info: Building FFTW
┌ Warning: `replace(s::AbstractString, pat, f)` is deprecated, use `replace(s, pat => f)` instead.
│   caller = makealiases(::String) at build_fftw.jl:26
└ @ Main.__anon__ build_fftw.jl:26
┌ Error: ------------------------------------------------------------
│ # Build failed for FFTW
│   exception =
│    LoadError: LoadError: UndefVarError: Libdl not defined
│    Stacktrace:
│     [1] makealiases(::String) at /Users/navid/.julia/v0.7/FFTW/deps/build_fftw.jl:27
│     [2] top-level scope
│     [3] include at ./boot.jl:292 [inlined]
│     [4] include_relative(::Module, ::String) at ./loading.jl:521
│     [5] include at ./sysimg.jl:26 [inlined]
│     [6] include(::String) at ./loading.jl:555
│     [7] top-level scope at /Users/navid/.julia/v0.7/FFTW/deps/build.jl:34
│     [8] include at ./boot.jl:292 [inlined]
│     [9] include_relative(::Module, ::String) at ./loading.jl:521
│     [10] include at ./sysimg.jl:26 [inlined]
│     [11] include(::String) at ./loading.jl:555
│     [12] top-level scope
│     [13] eval at ./boot.jl:295 [inlined]
│     [14] eval at ./sysimg.jl:71 [inlined]
│     [15] evalfile(::String, ::Array{String,1}) at ./loading.jl:550 (repeats 2 times)
│     [16] #2 at ./none:12 [inlined]
│     [17] cd(::getfield(, Symbol("##2#5")){String}, ::String) at ./file.jl:70
│     [18] (::getfield(, Symbol("##1#3")))(::IOStream) at ./none:11
│     [19] open(::getfield(, Symbol("##1#3")), ::String, ::String) at ./iostream.jl:310
│     [20] top-level scope
│     [21] eval at ./boot.jl:295 [inlined]
│     [22] eval(::Module, ::Expr) at ./sysimg.jl:71
│     [23] process_options(::Base.JLOptions) at ./client.jl:301
│     [24] _start() at ./client.jl:375
│    in expression starting at /Users/navid/.julia/v0.7/FFTW/deps/build_fftw.jl:36
│    in expression starting at /Users/navid/.julia/v0.7/FFTW/deps/build.jl:34
└ @ Main none:15
┌ Warning: ------------------------------------------------------------
│ # Build error summary
│
│ FFTW had build errors.
│
│  - packages with build errors remain installed in /Users/navid/.julia/v0.7
│  - build the package(s) and all dependencies with `Pkg.build("FFTW")`
│  - build a single package by running its `deps/build.jl` script
└ @ Base.Pkg.Entry entry.jl:650

Any thoughts?

julia> versioninfo()
Julia Version 0.7.0-DEV.3424
Commit 6afcb045b5 (2018-01-17 03:46 UTC)
Platform Info:
  OS: macOS (x86_64-apple-darwin14.5.0)
  CPU: Intel(R) Core(TM) i7-7820HQ CPU @ 2.90GHz
  WORD_SIZE: 64
  BLAS: libopenblas (USE64BITINT DYNAMIC_ARCH NO_AFFINITY Haswell)
  LAPACK: libopenblas64_
  LIBM: libopenlibm
  LLVM: libLLVM-3.9.1 (ORCJIT, skylake)
Environment: