我是RoR的新手，我正在尝试安装Mysql2 -v '0.3.11'。我有OS X Mountain Lion，导轨3.2.6，ruby 1.9.3。
以下是我得到的错误。 我到处找，什么也没找到。
$gem install mysql2 -v '0.3.11'
Building native extensions. This could take a while...
ERROR: Error installing mysql2:
ERROR: Failed to build gem native extension.
/Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/bin/ruby extconf.rb
checking for rb_thread_blocking_region()... yes
checking for rb_wait_for_single_fd()... yes
checking for mysql.h... yes
checking for errmsg.h... yes
checking for mysqld_error.h... yes
creating Makefile
make
compiling client.c
In file included from client.c:1:
In file included from ./mysql2_ext.h:8:
In file included from /Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/ruby.h:32:
/Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/ruby/ruby.h:105:37: error: 'ruby_check_sizeof_long' declared as an array with a negative size
typedef char ruby_check_sizeof_long[SIZEOF_LONG == sizeof(long) ? 1 : -1];
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/x86_64-darwin12.0.0/ruby/config.h:24:21: note: expanded from macro 'SIZEOF_LONG'
#define SIZEOF_LONG 8
^
In file included from client.c:1:
In file included from ./mysql2_ext.h:8:
In file included from /Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/ruby.h:32:
/Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/ruby/ruby.h:109:38: error: 'ruby_check_sizeof_voidp' declared as an array with a negative size
typedef char ruby_check_sizeof_voidp[SIZEOF_VOIDP == sizeof(void*) ? 1 : -1];
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/x86_64-darwin12.0.0/ruby/config.h:28:22: note: expanded from macro 'SIZEOF_VOIDP'
#define SIZEOF_VOIDP 8
^
In file included from client.c:1:
In file included from ./mysql2_ext.h:8:
In file included from /Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/ruby.h:32:
In file included from /Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/ruby/ruby.h:1377:
In file included from /Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/ruby/intern.h:34:
/Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/ruby/st.h:67:45: error: 'st_check_for_sizeof_st_index_t' declared as an array with a negative size
typedef char st_check_for_sizeof_st_index_t[SIZEOF_VOIDP == (int)sizeof(st_index_t) ? 1 : -1];
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/Users/curiosity/.rvm/rubies/ruby-1.9.3-p125/include/ruby-1.9.1/x86_64-darwin12.0.0/ruby/config.h:28:22: note: expanded from macro 'SIZEOF_VOIDP'
#define SIZEOF_VOIDP 8
^
3 errors generated.
make: *** [client.o] Error 1
Gem files will remain installed in /Users/curiosity/.rvm/gems/ruby-1.9.3-p125/gems/mysql2-0.3.11 for inspection.
Results logged to /Users/curiosity/.rvm/gems/ruby-1.9.3-p125/gems/mysql2-0.3.11/ext/mysql2/gem_make.out
感谢您的帮助。
您使用的是 RVM 而不是 10.8 附带的 Ruby。好。现在，停止使用10.8附带的MySQL。
安装和更新自制软件。现在运行
brew install mysql
使用项目中的/Gemfile来安装mysql2 gem。加
gem "mysql2"
到你的/Gemfile.然后通过运行
bundle install
让包管理器（自制软件和捆绑器）为您工作。
这应该可以解决您遇到的问题。
正如Deefour所说，我不得不使用RVM。答案归他，我只是无法评论他的答案。+1
但是rvm exec bundle install给了我一个错误：
rvm do bundle install已被移除，请改用rvm 1.9.2,1.9.3 do bundle install或rvm all do bundle install。
我用了 sudo rvm all do bundle install从那以后，一切都完美无缺。
我在 mac10.10 中也遇到了相同类型的错误，并使用以下适合我的命令：
-
安装和升级自制软件：
brew install mysql
-
使用以下方法运行安装 Mysql gem 文件：
gem install mysql2 -v '0.3.11'
-
运行捆绑包安装