error occurred while installing pg (0.15.1), and Bundler cannot continue

Question

I'm trying to run bundle install before starting a rails server and keep getting this error

An error occurred while installing pg (0.15.1), and Bundler cannot continue.
Make sure that `gem install pg -v '0.15.1'` succeeds before bundling.

Note that I've already tried installing postgres and I've already tried fixing the path to pg_config

Any idea what's going on?

The entire portion of the log reads:

Installing pg (0.15.1) with native extensions 
Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

        /usr/local/rvm/rubies/ruby-1.9.3-p392/bin/ruby extconf.rb 
checking for pg_config... yes
Using config values from /usr/bin/pg_config
checking for libpq-fe.h... yes
checking for libpq/libpq-fs.h... yes
checking for pg_config_manual.h... yes
checking for PQconnectdb() in -lpq... yes
checking for PQconnectionUsedPassword()... yes
checking for PQisthreadsafe()... yes
checking for PQprepare()... yes
checking for PQexecParams()... yes
checking for PQescapeString()... yes
checking for PQescapeStringConn()... yes
checking for PQescapeLiteral()... yes
checking for PQescapeIdentifier()... yes
checking for PQgetCancel()... yes
checking for lo_create()... yes
checking for pg_encoding_to_char()... yes
checking for pg_char_to_encoding()... yes
checking for PQsetClientEncoding()... yes
checking for PQlibVersion()... yes
checking for PQping()... yes
checking for PQsetSingleRowMode()... no
checking for rb_encdb_alias()... yes
checking for rb_enc_alias()... yes
checking for rb_thread_call_without_gvl()... yes
checking for rb_thread_call_with_gvl()... yes
checking for rb_thread_fd_select()... yes
checking for rb_w32_wrap_io_handle()... no
checking for PGRES_COPY_BOTH in libpq-fe.h... no
checking for PGRES_SINGLE_TUPLE in libpq-fe.h... no
checking for struct pgNotify.extra in libpq-fe.h... yes
checking for unistd.h... yes
checking for ruby/st.h... yes
creating extconf.h
creating Makefile

make
compiling gvl_wrappers.c
compiling pg.c
pg.c: In function ‘Init_pg_ext’:
pg.c:384: error: ‘PQPING_OK’ undeclared (first use in this function)
pg.c:384: error: (Each undeclared identifier is reported only once
pg.c:384: error: for each function it appears in.)
pg.c:386: error: ‘PQPING_REJECT’ undeclared (first use in this function)
pg.c:388: error: ‘PQPING_NO_RESPONSE’ undeclared (first use in this function)
pg.c:390: error: ‘PQPING_NO_ATTEMPT’ undeclared (first use in this function)
make: *** [pg.o] Error 1


Gem files will remain installed in /usr/local/rvm/gems/ruby-1.9.3-p392/gems/pg-0.15.1   for inspection.
Results logged to /usr/local/rvm/gems/ruby-1.9.3-p392/gems/pg-0.15.1/ext/gem_make.out
An error occurred while installing pg (0.15.1), and Bundler cannot continue.
Make sure that `gem install pg -v '0.15.1'` succeeds before bundling.

Answer 1

Questioner did not specify the OS.

On Ubuntu and other Debian flavors, try this:

sudo apt-get install libpq-dev

This should automatically pull in other dependencies if you don't already have them installed.

Looks like dooleyburger's answer is appropriate for various shades of Red Hat.

Answer 2

I'm using CentOS 6.3 and installing both postgres-libs postgres-devel worked for me (per: https://serverfault.com/questions/316703/how-to-install-libpq-dev-on-centos-5-5)

sudo yum install postgresql-libs postgresql-devel