使用rvm在Mac OS Lion上安装pg gem
212-178-13-214:~ igorfedoronchuk$ gem install pg Building native extensions. This could take a while... /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/site_ruby/1.9.1/rubygems/ext/builder.rb:48: warning: Insecure world writable dir /usr/local/bin in PATH, mode 040777 ERROR: Error installing pg: ERROR: Failed to build gem native extension. /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/bin/ruby extconf.rb checking for pg_config... yes Using config values from /usr/bin/pg_config checking for libpq-fe.h... *** 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=/Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/bin/ruby --with-pg --without-pg --with-pg-dir --without-pg-dir --with-pg-include --without-pg-include=${pg-dir}/include --with-pg-lib --without-pg-lib=${pg-dir}/lib --with-pg-config --without-pg-config --with-pg_config --without-pg_config /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:368:in `try_do': The complier failed to generate an executable file. (RuntimeError) You have to install development tools first. from /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:452:in `try_cpp' from /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:853:in `block in find_header' from /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:693:in `block in checking_for' from /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:280:in `block (2 levels) in postpone' from /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:254:in `open' from /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:280:in `block in postpone' from /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:254:in `open' from /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:276:in `postpone' from /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:692:in `checking_for' from /Users/igorfedoronchuk/.rvm/rubies/ruby-1.9.2-p180/lib/ruby/1.9.1/mkmf.rb:852:in `find_header' from extconf.rb:36:in `' Gem files will remain installed in /Users/igorfedoronchuk/.rvm/gems/ruby-1.9.2-p180@global/gems/pg-0.12.0 for inspection. Results logged to /Users/igorfedoronchuk/.rvm/gems/ruby-1.9.2-p180@global/gems/pg-0.12.0/ext/gem_make.out 从http://www.postgresql.org/download/macosx/下载并安装Postgres（版本9.1）
我试图用brew安装postgres – 没有结果。
如何解决这个问题？ 谢谢
错误消息（“您必须首先安装开发工具。”）说明了一切。 首先安装Xcode，然后尝试安装pg gem。
此外，您不必在Lion上安装第三方PostgreSQL，因为它已经包含在内。
我遇到了同样的问题，这里是我找到解决方案的地方
希望这可以帮助！