title: Failed building wheel for readline - when installing Rekall on OSX
body: <p>When installing Rekal on OSX I do the following steps: </p>
  
  <pre><code>virtualenv MyEnv
  source MyEnv/bin/activate
  pip install --upgrade setuptools pip wheel
  pip install rekall
  </code></pre>
  
  <p>The installation fails with the following error: </p>
  
  <pre><code>&gt;   Building wheel for readline (setup.py) ... error   ERROR: Command
  &gt; errored out with exit status 1:    command:
  &gt; /Users/mg/Documents/Rekall/MyEnv/bin/python -u -c 'import sys,
  &gt; setuptools, tokenize; sys.argv[0] =
  &gt; '"'"'/private/var/folders/xh/1xkfq26532j97q23qw5pdhs40000gn/T/pip-install-wojwzd/readline/setup.py'"'"';
  &gt; __file__='"'"'/private/var/folders/xh/1xkfq26532j97q23qw5pdhs40000gn/T/pip-install-wojwzd/readline/setup.py'"'"';f=getattr(tokenize,
  &gt; '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"',
  &gt; '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))'
  &gt; bdist_wheel -d
  &gt; /private/var/folders/xh/1xkfq26532j97q23qw5pdhs40000gn/T/pip-wheel-l11bWR
  &gt; --python-tag cp27
  &gt;        cwd: /private/var/folders/xh/1xkfq26532j97q23qw5pdhs40000gn/T/pip-install-wojwzd/readline/
  &gt; Complete output (195 lines):
  &gt;      ============ Building the readline library ============
  &gt;      x readline-6.2/   x readline-6.2/doc/   x readline-6.2/doc/Makefile.in   x readline-6.2/doc/texinfo.tex   x
  &gt; readline-6.2/doc/version.texi   x readline-6.2/doc/fdl.texi   x
  &gt; readline-6.2/doc/rlman.texi   x readline-6.2/doc/rltech.texi   x
  &gt; readline-6.2/doc/rluser.texi   x readline-6.2/doc/rluserman.texi   x
  &gt; readline-6.2/doc/history.texi   x readline-6.2/doc/hstech.texi   x
  &gt; readline-6.2/doc/hsuser.texi   x readline-6.2/doc/readline.3   x
  &gt; readline-6.2/doc/history.3   x readline-6.2/doc/texi2dvi   x
  &gt; readline-6.2/doc/texi2html   x readline-6.2/doc/readline.ps   x
  &gt; readline-6.2/doc/history.ps   x readline-6.2/doc/rluserman.ps   x
  &gt; readline-6.2/doc/readline.dvi   x readline-6.2/doc/history.dvi   x
  &gt; readline-6.2/doc/rluserman.dvi   x readline-6.2/doc/readline.info   x
  &gt; readline-6.2/doc/history.info   x readline-6.2/doc/rluserman.info   x
  &gt; readline-6.2/doc/readline.html   x readline-6.2/doc/history.html   x
  &gt; readline-6.2/doc/rluserman.html   x readline-6.2/doc/readline.0   x
  &gt; readline-6.2/doc/history.0   x readline-6.2/doc/readline_3.ps   x
  &gt; readline-6.2/doc/history_3.ps   x readline-6.2/doc/history.pdf   x
  &gt; readline-6.2/doc/readline.pdf   x readline-6.2/doc/rluserman.pdf   x
  &gt; readline-6.2/examples/   x readline-6.2/examples/autoconf/   x
  &gt; readline-6.2/examples/autoconf/BASH_CHECK_LIB_TERMCAP   x
  &gt; readline-6.2/examples/autoconf/RL_LIB_READLINE_VERSION   x
  &gt; readline-6.2/examples/autoconf/wi_LIB_READLINE   x
  &gt; readline-6.2/examples/rlfe/   x readline-6.2/examples/rlfe/ChangeLog  
  &gt; x readline-6.2/examples/rlfe/Makefile.in   x
  &gt; readline-6.2/examples/rlfe/README   x
  &gt; readline-6.2/examples/rlfe/config.h.in   x
  &gt; readline-6.2/examples/rlfe/configure   x
  &gt; readline-6.2/examples/rlfe/configure.in   x
  &gt; readline-6.2/examples/rlfe/extern.h   x
  &gt; readline-6.2/examples/rlfe/os.h   x readline-6.2/examples/rlfe/pty.c  
  &gt; x readline-6.2/examples/rlfe/rlfe.c   x
  &gt; readline-6.2/examples/rlfe/screen.h   x
  &gt; readline-6.2/examples/Makefile.in   x
  &gt; readline-6.2/examples/excallback.c   x readline-6.2/examples/fileman.c
  &gt; x readline-6.2/examples/manexamp.c   x
  &gt; readline-6.2/examples/readlinebuf.h   x
  &gt; readline-6.2/examples/rl-fgets.c   x readline-6.2/examples/rlcat.c   x
  &gt; readline-6.2/examples/rlevent.c   x readline-6.2/examples/rltest.c   x
  &gt; readline-6.2/examples/rl.c   x readline-6.2/examples/rlptytest.c   x
  &gt; readline-6.2/examples/rlversion.c   x
  &gt; readline-6.2/examples/histexamp.c   x readline-6.2/examples/Inputrc  
  &gt; x readline-6.2/examples/rlwrap-0.30.tar.gz   x readline-6.2/support/  
  &gt; x readline-6.2/support/config.guess   x
  &gt; readline-6.2/support/config.rpath   x readline-6.2/support/config.sub 
  &gt; x readline-6.2/support/install.sh   x readline-6.2/support/mkdirs   x
  &gt; readline-6.2/support/mkdist   x readline-6.2/support/mkinstalldirs   x
  &gt; readline-6.2/support/shobj-conf   x readline-6.2/support/shlib-install
  &gt; x readline-6.2/support/wcwidth.c   x readline-6.2/shlib/   x
  &gt; readline-6.2/shlib/Makefile.in   x readline-6.2/COPYING   x
  &gt; readline-6.2/README   x readline-6.2/MANIFEST   x readline-6.2/INSTALL
  &gt; x readline-6.2/CHANGELOG   x readline-6.2/CHANGES   x
  &gt; readline-6.2/NEWS   x readline-6.2/USAGE   x readline-6.2/aclocal.m4  
  &gt; x readline-6.2/config.h.in   x readline-6.2/configure   x
  &gt; readline-6.2/configure.in   x readline-6.2/Makefile.in   x
  &gt; readline-6.2/ansi_stdlib.h   x readline-6.2/chardefs.h   x
  &gt; readline-6.2/history.h   x readline-6.2/histlib.h   x
  &gt; readline-6.2/keymaps.h   x readline-6.2/posixdir.h   x
  &gt; readline-6.2/posixjmp.h   x readline-6.2/readline.h   x
  &gt; readline-6.2/posixselect.h   x readline-6.2/posixstat.h   x
  &gt; readline-6.2/rlconf.h   x readline-6.2/rldefs.h   x
  &gt; readline-6.2/rlmbutil.h   x readline-6.2/rlprivate.h   x
  &gt; readline-6.2/rlshell.h   x readline-6.2/rlstdc.h   x
  &gt; readline-6.2/rltty.h   x readline-6.2/rltypedefs.h   x
  &gt; readline-6.2/rlwinsize.h   x readline-6.2/tcap.h   x
  &gt; readline-6.2/tilde.h   x readline-6.2/xmalloc.h   x
  &gt; readline-6.2/bind.c   x readline-6.2/callback.c   x
  &gt; readline-6.2/compat.c   x readline-6.2/complete.c   x
  &gt; readline-6.2/display.c   x readline-6.2/emacs_keymap.c   x
  &gt; readline-6.2/funmap.c   x readline-6.2/input.c   x
  &gt; readline-6.2/isearch.c   x readline-6.2/keymaps.c   x
  &gt; readline-6.2/kill.c   x readline-6.2/macro.c   x readline-6.2/mbutil.c
  &gt; x readline-6.2/misc.c   x readline-6.2/nls.c   x readline-6.2/parens.c
  &gt; x readline-6.2/readline.c   x readline-6.2/rltty.c   x
  &gt; readline-6.2/savestring.c   x readline-6.2/search.c   x
  &gt; readline-6.2/shell.c   x readline-6.2/signals.c   x
  &gt; readline-6.2/terminal.c   x readline-6.2/text.c   x
  &gt; readline-6.2/tilde.c   x readline-6.2/undo.c   x readline-6.2/util.c  
  &gt; x readline-6.2/vi_keymap.c   x readline-6.2/vi_mode.c   x
  &gt; readline-6.2/xfree.c   x readline-6.2/xmalloc.c   x
  &gt; readline-6.2/history.c   x readline-6.2/histexpand.c   x
  &gt; readline-6.2/histfile.c   x readline-6.2/histsearch.c   x
  &gt; readline-6.2/patchlevel   patching file vi_mode.c   patching file
  &gt; callback.c   patching file support/shobj-conf   patching file
  &gt; patchlevel   patching file input.c   patching file patchlevel  
  &gt; patching file vi_mode.c   patching file patchlevel   checking build
  &gt; system type... i386-apple-darwin18.7.0   checking host system type...
  &gt; i386-apple-darwin18.7.0
  &gt;      Beginning configuration for readline-6.2 for i386-apple-darwin18.7.0
  &gt;      checking whether make sets $(MAKE)... yes   checking for gcc... gcc   checking for C compiler default output file name...   configure:
  &gt; error: in
  &gt; `/private/var/folders/xh/1xkfq26532j97q23qw5pdhs40000gn/T/pip-install-wojwzd/readline/rl/readline-lib':
  &gt; configure: error: C compiler cannot create executables   See
  &gt; `config.log' for more details.
  &gt;      ============ Building the readline extension module ============
  &gt;      running bdist_wheel   running build   running build_ext   building 'readline' extension   creating build   creating
  &gt; build/temp.macosx-10.14-intel-2.7   creating
  &gt; build/temp.macosx-10.14-intel-2.7/Modules   creating
  &gt; build/temp.macosx-10.14-intel-2.7/Modules/2.x   cc
  &gt; -fno-strict-aliasing -fno-common -dynamic -g -Os -pipe -fno-common -fno-strict-aliasing -fwrapv -DENABLE_DTRACE -DMACOSX -DNDEBUG -Wall -Wstrict-prototypes -Wshorten-64-to-32 -DNDEBUG -g -fwrapv -Os -Wall -Wstrict-prototypes -DENABLE_DTRACE -arch i386 -arch x86_64 -pipe -DHAVE_RL_CALLBACK -DHAVE_RL_CATCH_SIGNAL -DHAVE_RL_COMPLETION_APPEND_CHARACTER -DHAVE_RL_COMPLETION_DISPLAY_MATCHES_HOOK -DHAVE_RL_COMPLETION_MATCHES -DHAVE_RL_COMPLETION_SUPPRESS_APPEND -DHAVE_RL_PRE_INPUT_HOOK -I. -I/System/Library/Frameworks/Python.framework/Versions/2.7/include/python2.7
  &gt; -c Modules/2.x/readline.c -o build/temp.macosx-10.14-intel-2.7/Modules/2.x/readline.o
  &gt; -Wno-strict-prototypes   Modules/2.x/readline.c:720:22: warning: implicit conversion loses integer precision: 'long' to 'int'
  &gt; [-Wshorten-64-to-32]
  &gt;               result = PyInt_AsLong(r);
  &gt;                      ~ ^~~~~~~~~~~~~~~   1 warning generated.   creating build/lib.macosx-10.14-intel-2.7   cc -bundle -undefined
  &gt; dynamic_lookup -Wl,-F.
  &gt; build/temp.macosx-10.14-intel-2.7/Modules/2.x/readline.o
  &gt; readline/libreadline.a readline/libhistory.a -lncurses -o
  &gt; build/lib.macosx-10.14-intel-2.7/readline.so   clang: error: no such
  &gt; file or directory: 'readline/libreadline.a'   clang: error: no such
  &gt; file or directory: 'readline/libhistory.a'   error: command 'cc'
  &gt; failed with exit status 1   ----------------------------------------  
  &gt; ERROR: Failed building wheel for readline
  </code></pre>
  
  <p><strong>How can I fix that error?</strong></p>