问题
I'm trying to install PostgreSQL's pg gem for Ruby.
I issued the following command:
gem install pg
I installed Ruby 1.9.2 using RVM.
The above command shows me the following error.
The error is :
Building native extensions. This could take a while...
ERROR: Error installing pg:
ERROR: Failed to build gem native extension.
/home/User/.rvm/rubies/ruby-1.9.2-preview3/bin/ruby extconf.rb
checking for pg_config... yes
checking for libpq-fe.h... yes
checking for libpq/libpq-fs.h... yes
checking for PQconnectdb() in -lpq... no
checking for PQconnectdb() in -llibpq... no
checking for PQconnectdb() in -lms/libpq... no
Can't find the PostgreSQL client library (libpq)
*** 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/User/.rvm/rubies/ruby-1.9.2-preview3/bin/ruby
--with-pg
--without-pg
--with-pg-config
--without-pg-config
--with-pg-dir
--without-pg-dir
--with-pg-include
--without-pg-include=${pg-dir}/include
--with-pg-lib
--without-pg-lib=${pg-dir}/lib
--enable-static-build
--disable-static-build
--with-pqlib
--without-pqlib
--with-libpqlib
--without-libpqlib
--with-ms/libpqlib
--without-ms/libpqlib
Gem files will remain installed in /home/user/.rvm/gems/ruby-1.9.2-preview3/gems/pg-0.9.0 for inspection.
Results logged to /home/user/.rvm/gems/ruby-1.9.2-preview3/gems/pg-0.9.0/ext/gem_make.out
I don't know what is the error...
回答1:
You need install the postgreSQL dev package with header of PostgreSQL
sudo apt-get install libpq-dev
回答2:
After reading and thrashing around for 2 days, and trying many things found in other notes the following single line was the cure for me on Ubuntu Lucid 10.04 mixed with some Maverick packages and RVM (ruby 1.9.2-p290, rvm 1.10.2 rubygems 1.8.15, rails 3.0.1, postgres 8.4.10) :
gem install pg -- --with-pg-lib=/usr/lib
the result:
Building native extensions. This could take a while...
Successfully installed pg-0.13.1
1 gem installed
Installing ri documentation for pg-0.13.1...
Installing RDoc documentation for pg-0.13.1...
{yea - finally success} !! !note that the output from running pg_config lacks the item -lpq in the LIBS variable on my Ubuntu / Postresql install!!
and why the switch from pq to pg in certain places -- confusing to newbie ??
the thing I still do not understand is the double set of -- and --with(option but I'm way beyond my depth anyway
回答3:
I'm on Ubuntu 12.10 and running this command:
apt-get install libpq-dev
helped me - after that ran gem install pg -v "0.14.1", and all good now
回答4:
Need to add package
sudo apt-get install libpq-dev
to install pg gem in RoR
回答5:
In Ubuntu this works for me, I hope help you:
sudo apt-get install libpq-dev
and
gem install pg -- --with-pg-lib=/usr/lib
回答6:
Installing libpq-dev did not work for me. I also needed to install build-essential
sudo apt-get install libpq-dev build-essential
回答7:
Simple solution for ubuntu users...
First uninstall all postgres packages, then run these commads...
sudo apt-get install postgresql
sudo apt-get install postgresql-client libpq5 libpq-dev
# for rvm (single user)
mv ~/.rvm/usr/lib ~/.rvm/usr/lib_rvm
# for rvm (multi-user)
mv /usr/local/rvm/usr/lib /usr/local/rvm/usr/lib_rvm
gem install pg -- --with-pg-lib=/usr/lib
Then run 'bundle install'. Every thing will be fine. Have a good day!
回答8:
For .RVM users it will be better:
rvmsudo gem install pg -- --with-pg-lib=/usr/lib
it worked for me (after i saw jdupont version)
回答9:
If you have libpq-dev installed and are still having this problem it is likely due to conflicting versions of OpenSSL's libssl and friends - the Ubuntu system version in /usr/lib (which libpq is built against) and a second version RVM installed in $HOME/.rvm/usr/lib (or /usr/local/rvm/usr/lib if it's a system install). You can verify this by temporarily renaming $HOME/.rvm/usr/lib and seeing if "gem install pg" works.
To solve the problem have rvm rebuild using the system OpenSSL libraries (you may need to manually remove libssl.* and libcrypto.* from the rvm/usr/lib dir):
rvm reinstall 1.9.3 --with-openssl-dir=/usr
This finally solved the problem for me on Ubunto 12.04.
回答10:
This solved the problem for me on Ubuntu 12.04 after every suggestion here had failed.
rvmsudo gem install pg -v '0.12.2' -- --with-pg-lib=/usr/include/postgresql
回答11:
Try this
sudo apt-get install postgresql postgresql-contrib libpq-dev
You should install PG Database server in the first place to install clients. Afterwards, you install clients.
See this blog post to know about setting up PostGresSQL for the first time for Ruby on Rails development.
回答12:
I was trying to setup a Rails project in my freshly installed Ubuntu 16.04. I ran into the same issue while running bundle. Running
sudo apt-get install aptitude
followed by
sudo apt-get install libpq-dev
Solved it for me.
回答13:
For anyone who is still having issues after trying all the answers on this page, the following (finally) worked:
sudo apt-get install libgmp3-dev
gem install pg
This was after doing everything else mentioned on this page.
postgresql 9.5.8
Ubuntu 16.10
回答14:
I had the same problem, and tried a lot of different variants. After some tries I became able to sudo gem install, but still have problem to install it without sudo.
Finally I found a decission - reinstalling of rvm helped me. Probably it can save time somebody else.
回答15:
Another solution to this problem is to install PostgreSQL using Homebrew/linuxbrew:
brew install postgresql
As a matter of habit I don't like to use sudo unless I have to.
回答16:
For those trying to install Redmine, I missed sudo apt-get install ruby-all-dev after trying all of the above.
Initial error being mkmf.rb can't find header files for ruby at /usr/lib/ruby/include/ruby.h.
回答17:
apt-get install ruby-dev worked for me.
来源：https://stackoverflow.com/questions/53427182/unable-to-start-rails-server-for-a-rails-application