Warning: file_get_contents(/data/phpspider/zhask/data//catemap/5/ruby/21.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
Ruby c_uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuue):(无效)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3344:24:警告_Ruby_Macos Catalina - Fatal编程技术网

Ruby c_uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuue):(无效)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3344:24:警告

Ruby c_uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuue):(无效)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3344:24:警告,ruby,macos-catalina,Ruby,Macos Catalina,c_uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuue):(无效)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3344:24:警告:表达式结果未使用[-Wunused值] 断言(((“libev:处理计时器时发现的负ev_计时器重复值”,w->repeat>0.); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

c_uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuue):(无效)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3344:24:警告:表达式结果未使用[-Wunused值] 断言(((“libev:处理计时器时发现的负ev_计时器重复值”,w->repeat>0.); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25:注意:从宏“assert”展开 (uuu内置_uuexpect(!(e),0)?uu assert_urtn(uuu func,uuu文件,uuu行,#e):(void)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3406:24:警告:表达式结果未使用[-Wunused值] 断言(((“libev:ev_定期重新调度回调在过去返回的时间”,ev_at(w)>=ev_rt_now)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25:注意:从宏“assert”展开 (uuu内置_uuexpect(!(e),0)?uu assert_urtn(uuu func,uuu文件,uuu行,#e):(void)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3551:1:警告:非void函数不返回值[-Wreturn type] } ^ ../../libev/ev.c:3568:12:警告:表达式结果未使用[-Wunused值] 断言(((“libev:ev_循环递归在释放期间检测到”,loop_done!=EVBREAK_RECURSE)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25:注意:从宏“assert”展开 (uuu内置_uuexpect(!(e),0)?uu assert_urtn(uuu func,uuu文件,uuu行,#e):(void)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3737:9:错误:C99[-Werror,-Wimplicit函数声明]中函数“rb_thread_call_without_gvl”的隐式声明无效 没有gvl的rb_线程调用(ev_后端轮询,(void*)和轮询参数,RUBY_UBF_IO,0); ^ ../../libev/ev.c:3752:22:警告:表达式结果未使用[-Wunused值] 断言((“libev:pipe_w未激活,但未写入”,ev_已激活(&pipe_w)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25:注意:从宏“assert”展开 (uuu内置_uuexpect(!(e),0)?uu assert_urtn(uuu func,uuu文件,uuu行,#e):(void)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3926:12:警告:表达式结果未使用[-Wunused值] 断言(((“libev:ev_io__start用负fd调用”,fd>=0)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25:注意:从宏“assert”展开 (uuu内置_uuexpect(!(e),0)?uu assert_urtn(uuu func,uuu文件,uuu行,#e):(void)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3927:12:警告:表达式结果未使用[-Wunused值] 断言(((“使用非法事件掩码调用libev:ev_io_start”!(w->events&~(ev_IOFDSET | ev_READ | ev_WRITE))); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25:注意:从宏“assert”展开 (uuu内置_uuexpect(!(e),0)?uu assert_urtn(uuu func,uuu文件,uuu行,#e):(void)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3936:12:警告:表达式结果未使用[-Wunused值] 断言((((libev:ev_io_start用损坏的观察程序调用),((WL)w)->next!=(WL)w)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25:注意:从宏“assert”展开 (uuu内置_uuexpect(!(e),0)?uu assert_urtn(uuu func,uuu文件,uuu行,#e):(void)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3951:12:警告:表达式结果未使用[-Wunused值] 断言(((“libev:ev_io_stop被非法的fd调用(启动后必须保持不变!)),w->fd>=0&&w->fdrepeat>=0.); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25:注意:从宏“assert”展开 (uuu内置_uuexpect(!(e),0)?uu assert_urtn(uuu func,uuu文件,uuu行,#e):(void)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:3999:14:警告:表达式结果未使用[-Wunused值] 断言(((“libev:内部计时器堆损坏”,ANHE_w(计时器[active])==(WT)w)); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25:注意:从宏“assert”展开 (uuu内置_uuexpect(!(e),0)?uu assert_urtn(uuu func,uuu文件,uuu行,#e):(void)0) ^ 在nio4r_ext.c中包含的文件中:7: ../../libev/ev.c:4061:16:警告:表达式结果未使用[-Wunused值] 断言(((“libev:ev_periodic_start使用负间隔值调用”,w->interval>=0.); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25:注意:从宏“assert”展开 (_u)内置_
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.
Make sure that `gem install nio4r -v '1.2.1' --source 'https://rubygems.org/'` succeeds before bundling.
    ERROR: Failed to build gem native extension.

    current directory: /Users/admin/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/nio4r-1.2.1/ext/nio4r
/Users/admin/.rbenv/versions/2.3.1/bin/ruby -r ./siteconf20201129-28103-lmj40x.rb extconf.rb
checking for unistd.h... yes
checking for rb_thread_blocking_region()... no
checking for rb_thread_call_without_gvl()... yes
checking for sys/select.h... yes
checking for poll.h... yes
checking for sys/epoll.h... no
checking for sys/event.h... yes
checking for sys/queue.h... yes
checking for port.h... no
checking for sys/resource.h... yes
creating Makefile

To see why this extension failed to compile, please check the mkmf.log which can be found here:

  /Users/admin/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/extensions/x86_64-darwin-18/2.3.0-static/nio4r-1.2.1/mkmf.log

current directory: /Users/admin/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/nio4r-1.2.1/ext/nio4r
make "DESTDIR=" clean

current directory: /Users/admin/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/nio4r-1.2.1/ext/nio4r
make "DESTDIR="
compiling monitor.c
compiling nio4r_ext.c
In file included from nio4r_ext.c:7:
./../libev/ev.c:487:48: warning: '/*' within block comment [-Wcomment]
/*#define MIN_INTERVAL  0.00000095367431640625 /* 1/2**20, good till 2200 */
                                               ^
./../libev/ev.c:1829:31: warning: 'extern' variable has an initializer [-Wextern-initializer]
  EV_API_DECL struct ev_loop *ev_default_loop_ptr = 0; /* needs to be initialised to make it a definition despite extern */
                              ^
In file included from nio4r_ext.c:7:
In file included from ./../libev/ev.c:2694:
./../libev/ev_poll.c:110:18: warning: expression result unused [-Wunused-value]
        assert (("libev: poll() returned illegal result, broken BSD kernel?", p < polls + pollcnt));
                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3100:12: warning: expression result unused [-Wunused-value]
  assert (("libev: watcher has invalid priority", ABSPRI (w) >= 0 && ABSPRI (w) < NUMPRI));
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3103:14: warning: expression result unused [-Wunused-value]
    assert (("libev: pending watcher not on pending queue", pendings [ABSPRI (w)][w->pending - 1].w == w));
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3113:16: warning: expression result unused [-Wunused-value]
      assert (("libev: active index mismatch in heap", ev_active (ANHE_w (heap [i])) == i));
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3114:16: warning: expression result unused [-Wunused-value]
      assert (("libev: heap condition violated", i == HEAP0 || ANHE_at (heap [HPARENT (i)]) <= ANHE_at (heap [i])));
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3115:16: warning: expression result unused [-Wunused-value]
      assert (("libev: heap at cache mismatch", ANHE_at (heap [i]) == ev_at (ANHE_w (heap [i]))));
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3126:16: warning: expression result unused [-Wunused-value]
      assert (("libev: active index mismatch", ev_active (ws [cnt]) == cnt + 1));
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3144:14: warning: expression result unused [-Wunused-value]
    assert (("libev: negative fd in fdchanges", fdchanges [i] >= 0));
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3157:24: warning: expression result unused [-Wunused-value]
              assert (("libev: io watcher list contains a loop", w != w2));
                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3161:20: warning: expression result unused [-Wunused-value]
          assert (("libev: inactive fd watcher on anfd list", ev_active (w) == 1));
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3162:20: warning: expression result unused [-Wunused-value]
          assert (("libev: fd mismatch between watcher and anfd", ((ev_io *)w)->fd == i));
                   ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3344:24: warning: expression result unused [-Wunused-value]
              assert (("libev: negative ev_timer repeat value found while processing timers", w->repeat > 0.));
                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3406:24: warning: expression result unused [-Wunused-value]
              assert (("libev: ev_periodic reschedule callback returned time in the past", ev_at (w) >= ev_rt_now));
                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3551:1: warning: non-void function does not return a value [-Wreturn-type]
}
^
./../libev/ev.c:3568:12: warning: expression result unused [-Wunused-value]
  assert (("libev: ev_loop recursion during release detected", loop_done != EVBREAK_RECURSE));
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3737:9: error: implicit declaration of function 'rb_thread_call_without_gvl' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
        rb_thread_call_without_gvl(ev_backend_poll, (void *)&poll_args, RUBY_UBF_IO, 0);
        ^
./../libev/ev.c:3752:22: warning: expression result unused [-Wunused-value]
            assert (("libev: pipe_w not active, but pipe not written", ev_is_active (&pipe_w)));
                     ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3926:12: warning: expression result unused [-Wunused-value]
  assert (("libev: ev_io_start called with negative fd", fd >= 0));
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3927:12: warning: expression result unused [-Wunused-value]
  assert (("libev: ev_io_start called with illegal event mask", !(w->events & ~(EV__IOFDSET | EV_READ | EV_WRITE))));
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3936:12: warning: expression result unused [-Wunused-value]
  assert (("libev: ev_io_start called with corrupted watcher", ((WL)w)->next != (WL)w));
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3951:12: warning: expression result unused [-Wunused-value]
  assert (("libev: ev_io_stop called with illegal fd (must stay constant after start!)", w->fd >= 0 && w->fd < anfdmax));
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3971:12: warning: expression result unused [-Wunused-value]
  assert (("libev: ev_timer_start called with negative timer repeat value", w->repeat >= 0.));
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:3999:14: warning: expression result unused [-Wunused-value]
    assert (("libev: internal timer heap corruption", ANHE_w (timers [active]) == (WT)w));
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:4061:16: warning: expression result unused [-Wunused-value]
      assert (("libev: ev_periodic_start called with negative interval value", w->interval >= 0.));
               ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:4093:14: warning: expression result unused [-Wunused-value]
    assert (("libev: internal periodic heap corruption", ANHE_w (periodics [active]) == (WT)w));
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:4130:12: warning: expression result unused [-Wunused-value]
  assert (("libev: ev_signal_start called with illegal signal number", w->signum > 0 && w->signum < EV_NSIG));
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:4133:12: warning: expression result unused [-Wunused-value]
  assert (("libev: a signal must not be attached to two different loops",
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:4251:12: warning: expression result unused [-Wunused-value]
  assert (("libev: child watchers are only supported in the default loop", loop == ev_default_loop_ptr));
           ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
In file included from nio4r_ext.c:7:
./../libev/ev.c:4830:14: warning: expression result unused [-Wunused-value]
    assert (("libev: loop to be embedded is not embeddable", backend & ev_embeddable_backends ()));
             ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/assert.h:93:25: note: expanded from macro 'assert'
    (__builtin_expect(!(e), 0) ? __assert_rtn(__func__, __FILE__, __LINE__, #e) : (void)0)
                        ^
30 warnings and 1 error generated.
make: *** [nio4r_ext.o] Error 1

make failed, exit code 2

Gem files will remain installed in /Users/admin/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/gems/nio4r-1.2.1 for inspection.
Results logged to /Users/admin/.rbenv/versions/2.3.1/lib/ruby/gems/2.3.0/extensions/x86_64-darwin-18/2.3.0-static/nio4r-1.2.1/gem_make.out
sudo gem install rails