Error installing EventMachine gem on OSX Yosemite

Question

Here is the full output of the error message:

    Fetching: eventmachine-1.0.3.gem (100%)
Building native extensions.  This could take a while...
ERROR:  Error installing eventmachine:
    ERROR: Failed to build gem native extension.

    /Users/Tyler/.rvm/rubies/ruby-2.2.0/bin/ruby -r ./siteconf20141229-47086-wfdm3m.rb extconf.rb
checking for rb_trap_immediate in ruby.h,rubysig.h... no
checking for rb_thread_blocking_region()... no
checking for inotify_init() in sys/inotify.h... no
checking for __NR_inotify_init in sys/syscall.h... no
checking for writev() in sys/uio.h... yes
checking for rb_wait_for_single_fd()... yes
checking for rb_enable_interrupt()... no
checking for rb_time_new()... yes
checking for sys/event.h... yes
checking for sys/queue.h... yes
creating Makefile

make "DESTDIR=" clean

make "DESTDIR="
compiling binder.cpp
compiling cmain.cpp
compiling ed.cpp
compiling em.cpp
em.cpp:827:9: error: use of undeclared identifier 'rb_thread_select'; did you mean 'rb_thread_fd_select'?
        return EmSelect (maxsocket+1, &fdreads, &fdwrites, &fderrors, &tv);
               ^~~~~~~~
               rb_thread_fd_select
./em.h:25:20: note: expanded from macro 'EmSelect'
  #define EmSelect rb_thread_select
                   ^
/Users/Tyler/.rvm/rubies/ruby-2.2.0/include/ruby-2.2.0/ruby/intern.h:454:5: note: 'rb_thread_fd_select' declared here
int rb_thread_fd_select(int, rb_fdset_t *, rb_fdset_t *, rb_fdset_t *, struct timeval *);
    ^
em.cpp:827:32: error: cannot initialize a parameter of type 'rb_fdset_t *' with an rvalue of type 'fd_set *'
        return EmSelect (maxsocket+1, &fdreads, &fdwrites, &fderrors, &tv);
                                      ^~~~~~~~
/Users/Tyler/.rvm/rubies/ruby-2.2.0/include/ruby-2.2.0/ruby/intern.h:454:42: note: passing argument to parameter here
int rb_thread_fd_select(int, rb_fdset_t *, rb_fdset_t *, rb_fdset_t *, struct timeval *);
                                         ^
em.cpp:946:6: error: use of undeclared identifier 'rb_thread_select'; did you mean 'rb_thread_fd_select'?
                                        EmSelect (0, NULL, NULL, NULL, &tv);
                                        ^~~~~~~~
                                        rb_thread_fd_select
./em.h:25:20: note: expanded from macro 'EmSelect'
  #define EmSelect rb_thread_select
                   ^
/Users/Tyler/.rvm/rubies/ruby-2.2.0/include/ruby-2.2.0/ruby/intern.h:454:5: note: 'rb_thread_fd_select' declared here
int rb_thread_fd_select(int, rb_fdset_t *, rb_fdset_t *, rb_fdset_t *, struct timeval *);
    ^
3 errors generated.
make: *** [em.o] Error 1

make failed, exit code 2

Has anyone seen an error like this before? I have the command line tools - never ran into an error compiling this gem on my old laptop also running Yosemite.

Answer 1

EventMachine 1.0.3 didn’t work with Ruby 2.2. This was fixed in EventMachine 1.0.4. You can most likely fix your situation by upgrading EventMachine with

bundle update eventmachine

Answer 2

For El Captain, this worked for me:

$ bundle update eventmachine # updated to v1.0.8
$ bundle config build.eventmachine --with-cppflags=-I/usr/local/opt/openssl/include
$ bundle install

Answer 3

if you have brew install, try

brew install openssl

and if it still says,

Warning: openssl-1.0.2e already installed

then run this command ,

brew link openssl --force

it will do the trick. :)