我使用的是Ruby on Rails 3.1预版本。我喜欢使用PostgreSQL,但问题是安装pg gem。它给了我以下错误:

$ gem install pg
Building native extensions.  This could take a while...
ERROR:  Error installing pg:
    ERROR: Failed to build gem native extension.

        /home/u/.rvm/rubies/ruby-1.9.2-p0/bin/ruby extconf.rb
checking for pg_config... no
No pg_config... trying anyway. If building fails, please try again with
 --with-pg-config=/path/to/pg_config
checking for libpq-fe.h... no
Can't find the 'libpq-fe.h header
*** 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=/home/u/.rvm/rubies/ruby-1.9.2-p0/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
    Gem files will remain installed in /home/u/.rvm/gems/ruby-1.9.2-p0/gems/pg-0.11.0 for inspection.
    Results logged to /home/u/.rvm/gems/ruby-1.9.2-p0/gems/pg-0.11.0/ext/gem_make.out

我怎么解决这个问题?


当前回答

在FreeBSD(9.1)上,必要的包是/usr/ports/database/postgresql-server*,安装时也会安装所需的头文件,使gem安装“pg”失败。这里的答案帮助我找到解决方案,但包名的差异需要进行一些搜索。

希望这能帮助人们在FreeBSD系统上搜索“-dev”包时避免一点挠头!

其他回答

我通过安装postgresql-common包解决了这个问题。这个包提供了pg_config二进制文件,这很可能是您所缺少的。

我最近升级到Mac OS X v10.10 (Yosemite),在构建pg gem时遇到了困难。

报告的错误是典型的:

Using config values from /usr/local/bin/pg_config
checking for libpq-fe.h... *** extconf.rb failed ***

我的解决方案是卸载pg gem,然后捆绑更新pg,用最新的gem替换gem。我确实运行了brew update;在Yosemite安装后进行brew升级,以获得我之前安装的软件包的最新版本。

只有卸载(sudo apt-get purge) libpq-dev并重新安装它才对我有用。

我刚刚在OSX上运行了brew和postgres@9.4。

我的解决方案是这样的:

CONFIGURE_ARGS="with-pg-include=/usr/local/opt/postgresql@9.4/include/" bundle install

在OS X和MacPorts上,PostgreSQL不再需要-devel包。安装pg gem的步骤如下:

~ > sudo port install postgresql-devel
...
Error: postgresql-devel has been replaced by postgresql91; please install that port instead
~ > gem install pg -v '0.17.1' -- --with-pg-config=/opt/local/lib/postgresql95/bin/pg_config

参见这篇文章。