我试过sudo gem install mysql2 -v'0.4.4'并且出错了。检查/var/lib/gems/2.3.0/extensions/x86_64-linux/2.3.0/mysql2-0.4.4/mkmf.log:
"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 */
所以在我看来ruby.h就是问题所在。但我可以在：
找到它/usr/include/ruby-2.3.0/ruby/ruby.h
/usr/include/ruby-2.3.0/ruby.h
我检查了Error while installing json gem 'mkmf.rb can't find header files for ruby'，但事实上我已经安装了ruby开发。
sudo dpkg -l | grep ruby也表明我有：
sudo dpkg -l | grep ruby
ii libruby2.3:amd64 2.3.1-2~16.04 amd64 Libraries necessary to run Ruby 2.3
ii rake 10.5.0-2 all ruby make-like utility
ii ruby 1:2.3.0+1 all Interpreter of object-oriented scripting language Ruby (default version)
ii ruby-bundler 1.11.2-1 all Manage Ruby application dependencies (runtime)
ii ruby-dev:amd64 1:2.3.0+1 amd64 Header files for compiling extension modules for Ruby (default version)
ii ruby-did-you-mean 1.0.0-2 all smart error messages for Ruby > 2.3
ii ruby-eventmachine 1.0.7-3build3 amd64 Ruby/EventMachine library
ii ruby-minitest 5.8.4-2 all Ruby test tools supporting TDD, BDD, mocking, and benchmarking
ii ruby-molinillo 0.4.3-1 all generic dependency resolution algorithm
ii ruby-mysql 2.9.1-1ubuntu1 amd64 MySQL module for Ruby
ii ruby-mysql2 0.4.3-2ubuntu2 amd64 simple, fast MySQL library for Ruby
ii ruby-net-http-persistent 2.9.4-1 all Manages persistent connections using Net::HTTP
ii ruby-net-telnet 0.1.1-2 all telnet client library
ii ruby-power-assert 0.2.7-1 all library showing values of variables and method calls in an expression
ii ruby-test-unit 3.1.7-2 all unit testing framework for Ruby
ii ruby-thor 0.19.1-2 all Ruby scripting framework
ii ruby2.3 2.3.1-2~16.04 amd64 Interpreter of object-oriented scripting language Ruby
ii ruby2.3-dev:amd64 2.3.1-2~16.04 amd64 Header files for compiling extension modules for the Ruby 2.3
ii rubygems-integration 1.10 all integration of Debian Ruby packages with Rubygems
那么我该如何解决这个问题呢？
答案 0 :(得分：2)
尝试安装gcc和make。这项工作适合我。
apt-get install gcc make