architecture x86_64 while running Haskell code, Haskell OSX iconv

Question

When I was compiling a working Haskell code on my computer, It's throwing this error of architecture x86_64. It was working fine on my friend's computer which is of the same architecture.

  $ ghc --make BoardMain.hs
    Linking BoardMain ...
    Undefined symbols for architecture x86_64:
      "_iconv", referenced from:
          _hs_iconv in libHSbase-4.9.1.0.a(iconv.o)
         (maybe you meant: _hs_iconv, _base_GHCziIOziEncodingziIconv_iconvEncoding5_closure , _base_GHCziIOziEncodingziIconv_iconvEncodingzuloc_info , _base_GHCziIOziEncodingziIconv_iconvEncoding9_info , _hs_iconv_open , _base_GHCziIOziEncodingziIconv_iconvEncoding10_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding11_info , _base_GHCziIOziEncodingziIconv_iconvEncoding7_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding8_info , _base_GHCziIOziEncodingziIconv_iconvEncoding11_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding8_closure , _base_GHCziIOziEncodingziIconv_iconvEncodingzuloc_closure , _hs_iconv_close , _base_GHCziIOziEncodingziIconv_iconvEncoding4_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding10_info , _base_GHCziIOziEncodingziIconv_iconvEncoding3_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding9_closure , _base_GHCziIOziEncodingziIconv_iconvEncoding2_closure , _base_GHCziIOziEncodingziIconv_iconvEncodingzuloc1_info , _base_GHCziIOziEncodingziIconv_iconvEncoding7_info , _base_GHCziIOziEncodingziIconv_iconvEncoding2_info , _base_GHCziIOziEncodingziIconv_iconvEncoding4_info , _base_GHCziIOziEncodingziIconv_iconvEncodingzuloc1_closure )
      "_iconv_close", referenced from:
          _hs_iconv_close in libHSbase-4.9.1.0.a(iconv.o)
         (maybe you meant: _hs_iconv_close)
      "_iconv_open", referenced from:
          _hs_iconv_open in libHSbase-4.9.1.0.a(iconv.o)
         (maybe you meant: _hs_iconv_open)
      "_locale_charset", referenced from:
          _localeEncoding in libHSbase-4.9.1.0.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)

Answer 1

The error isn't due to the architecture. The error is because of the another libiconv probably installed with MacPorts is at

/opt/local/lib as /opt/local/lib/libiconv.*

While compiling the code, it refers to Macports libiconv which is somehow different from OS X libiconv. We need the machine to use OS X libiconv so to make sure it uses the OS X libconv which is at

/usr/lib as /usr/lib/libiconv.*

we need to pass the extra library direction command to cabal or ghc .. while compiling by adding -L/usr/lib i.e.,

ghc -L/usr/lib --make file.hs
cabal exec -- ghc -L/usr/lib --make BoardMain.hs

You can even try adding extra-lib-dir: - /usr/lib to our stack.yaml. refer this for more information on this.

Or by deactivating libconv at /opt/local/lib If you are sure that they aren't going to break some link in some other file.