title: Link error with "stack install hoogle" on a mac
body: <p>New to stack and haskell. I am on lts-7.8, trying to run "stack install hoogle" get the following link error.</p>
  
  <pre><code>  Preprocessing executable 'hoogle' for hoogle-5.0.1...
      [1 of 1] Compiling Main             ( src/Main.hs, .stack-work/dist/x86_64-osx/Cabal-1.24.0.0/build/hoogle/hoogle-tmp/Main.o )
      Linking .stack-work/dist/x86_64-osx/Cabal-1.24.0.0/build/hoogle/hoogle ...
      Undefined symbols for architecture x86_64:
        "_iconv", referenced from:
            _hs_iconv in libHSbase-4.9.0.0.a(iconv.o)
           (maybe you meant: _base_GHCziIOziEncodingziIconv_iconvEncodingzuloc_info, _base_GHCziIOziEncodingziIconv_iconvEncoding2_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding11_info , _base_GHCziIOziEncodingziIconv_iconvEncoding6_info , _base_GHCziIOziEncodingziIconv_iconvEncoding_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding1_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding1_info , _base_GHCziIOziEncodingziIconv_iconvEncoding4_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding4_info , _base_GHCziIOziEncodingziIconv_iconvEncoding7_info , _base_GHCziIOziEncodingziIconv_iconvEncoding6_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding8_info , _hs_iconv_open , _base_GHCziIOziEncodingziIconv_iconvEncodingzuloc1_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding9_info , _base_GHCziIOziEncodingziIconv_iconvEncoding10_info , _base_GHCziIOziEncodingziIconv_iconvEncodingzuloc1_info , _base_GHCziIOziEncodingziIconv_iconvEncodingzuloc_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding3_closure , _hs_iconv_close , _base_GHCziIOziEncodingziIconv_iconvEncoding8_closure , _hs_iconv , _base_GHCziIOziEncodingziIconv_iconvEncoding_info , _base_GHCziIOziEncodingziIconv_iconvEncoding7_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding11_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding2_info , _base_GHCziIOziEncodingziIconv_iconvEncoding9_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding10_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding5_closure )
        "_iconv_close", referenced from:
            _hs_iconv_close in libHSbase-4.9.0.0.a(iconv.o)
           (maybe you meant: _hs_iconv_close)
        "_iconv_open", referenced from:
            _hs_iconv_open in libHSbase-4.9.0.0.a(iconv.o)
           (maybe you meant: _hs_iconv_open)
        "_locale_charset", referenced from:
            _localeEncoding in libHSbase-4.9.0.0.a(PrelIOUtils.o)
      ld: symbol(s) not found for architecture x86_64
      clang: error: linker command failed with exit code 1 (use -v to see invocation)
      `gcc' failed in phase `Linker'. (Exit code: 1)
  </code></pre>
  
  <p>Thanks in advance.</p>