如何在Ubuntu 16.04上使用Rails安装Nokogiri

Question

我正在尝试使用 gem 命令安装 Rails。

sudo gem install rails

在全新的Ubuntu 16.04版本上，已经安装了Ruby 2.3.1p112。在安装Rails期间，一旦完成获取Nokogiri操作，我会收到下面的错误提示：

Fetching: nokogiri-1.8.0.gem (100%)
Building native extensions.  This could take a while...
ERROR:  Error installing rails:
        ERROR: Failed to build gem native extension.

    current directory: /var/lib/gems/2.3.0/gems/nokogiri-1.8.0/ext/nokogiri
/usr/bin/ruby2.3 -r ./siteconf20170608-1635-1vnwqbn.rb extconf.rb
checking if the C compiler accepts ... *** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers.  Check the mkmf.log file for more details.  You may
need configuration options.

Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=/usr/bin/$(RUBY_BASE_NAME)2.3
        --help
        --clean
/usr/lib/ruby/2.3.0/mkmf.rb:456:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.
        from /usr/lib/ruby/2.3.0/mkmf.rb:571:in `block in try_compile'
        from /usr/lib/ruby/2.3.0/mkmf.rb:522:in `with_werror'
        from /usr/lib/ruby/2.3.0/mkmf.rb:571:in `try_compile'
        from extconf.rb:138:in `nokogiri_try_compile'
        from extconf.rb:162:in `block in add_cflags'
        from /usr/lib/ruby/2.3.0/mkmf.rb:629:in `with_cflags'
        from extconf.rb:161:in `add_cflags'
        from extconf.rb:407:in `<main>'

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

  /var/lib/gems/2.3.0/extensions/x86_64-linux/2.3.0/nokogiri-1.8.0/mkmf.log

extconf failed, exit code 1

Gem files will remain installed in /var/lib/gems/2.3.0/gems/nokogiri-1.8.0 for inspection.
Results logged to /var/lib/gems/2.3.0/extensions/x86_64-linux/2.3.0/nokogiri-1.8.0/gem_make.out

这是mkmf.log文件的内容：

"gcc -o conftest -I/usr/include/x86_64-linux-gnu/ruby-2.3.0 -I/usr/include/ruby-2.3.0/ruby/backward -I/usr/include/ruby-2.3.0 -I. -Wdate-time -D_FORTIFY_SOURCE=2   -g -O2 -fstack-protector-strong -Wformat -Werror=format-security -fPIC  conftest.c  -L. -L/usr/lib/x86_64-linux-gnu -L. -Wl,-Bsymbolic-functions -Wl,-z,relro -Wl,-z,now -fstack-protector -rdynamic -Wl,-export-dynamic     -lruby-2.3  -lpthread -lgmp -ldl -lcrypt -lm   -lc "
checked program was:
/* begin */
1: #include "ruby.h"
2:
3: int main(int argc, char **argv)
4: {
5:   return 0;
6: }
/* end */

我不知道哪里出了问题。日志也没有帮助，而且我已经尝试安装libgmp-dev、ruby-dev、zlib1g-dev和liblzma-dev了，因为这些被建议给那些在Nokogiri gem安装过程中遇到错误的人。

- McMutton

---

在Linux上使用RVM并尝试安装Rails时遇到问题的任何人，也可以查看https://dev59.com/GF0b5IYBdhLWcg3wVv-9。 - the Tin Man

我也遇到了同样的问题，找不到解决办法。 - tibbon

Answer 1

在一段时间的寻找缺失依赖项后，我运行了 mkmf.log 中的 gcc 命令，以防有一些编译错误消息被省略。

事实证明我并没有安装 gcc。一旦我安装了它，我就在安装过程中取得了一些进展，但最终还是遇到了另一个类似的错误。最后，安装下面列出的依赖项成功安装了 Rails。

在运行 gem install rails 之前，请确保您已安装以下依赖项：gcc、make、zlib1g-dev、sqlite3：

sudo apt-get install gcc make zlib1g-dev sqlite3

- McMutton