Not able to install pg gem - I this message: An error occurred while installing pg (1.2.3), and Bund-CodePudding

I'm on macOS Big Sur and recently installed homebrew. The installation is working fine and shows Your system is ready to brew. when I run brew doctor.

I've also successfully installed PostgreSQL using homebrew. The app uses ruby version 3.1.2 and Rails 7

Now I have a new Rails app and when I run bundle, I keep getting this error:

Installing pg 1.2.3 with native extensions
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

    current directory: /Users/max/.rvm/gems/ruby-3.1.2/gems/pg-1.2.3/ext
/Users/max/.rvm/rubies/ruby-3.1.2/bin/ruby -I /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0 -r ./siteconf20221017-65333-4ldjbt.rb extconf.rb
--with-cflags\=-Wno-error\=implicit-function-declaration
checking for pg_config... yes
Using config values from /usr/local/opt/libpq/bin/pg_config
*** 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/max/.rvm/rubies/ruby-3.1.2/bin/$(RUBY_BASE_NAME)
    --with-pg
    --without-pg
    --enable-windows-cross
    --disable-windows-cross
    --with-pg-config
    --without-pg-config
    --with-pg_config
    --without-pg_config
    --with-pg-dir
    --without-pg-dir
    --with-pg-include
    --without-pg-include=${pg-dir}/include
    --with-pg-lib
    --without-pg-lib=${pg-dir}/lib
/Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/mkmf.rb:498:in `try_do': The compiler failed to generate an executable file. (RuntimeError)
You have to install development tools first.
    from /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/mkmf.rb:591:in `try_link0'
    from /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/mkmf.rb:609:in `try_link'
    from extconf.rb:40:in `<main>'

To see why this extension failed to compile, please check the mkmf.log which can be found here:

  /Users/max/.rvm/gems/ruby-3.1.2/extensions/x86_64-darwin-19/3.1.0/pg-1.2.3/mkmf.log

extconf failed, exit code 1

Gem files will remain installed in /Users/max/.rvm/gems/ruby-3.1.2/gems/pg-1.2.3 for inspection.
Results logged to /Users/max/.rvm/gems/ruby-3.1.2/extensions/x86_64-darwin-19/3.1.0/pg-1.2.3/gem_make.out

  /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/rubygems/ext/builder.rb:95:in `run'
  /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/rubygems/ext/ext_conf_builder.rb:47:in `block in build'
  /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/tempfile.rb:317:in `open'
  /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/rubygems/ext/ext_conf_builder.rb:26:in `build'
  /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/rubygems/ext/builder.rb:161:in `build_extension'
  /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/rubygems/ext/builder.rb:195:in `block in build_extensions'
  /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/rubygems/ext/builder.rb:192:in `each'
  /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/rubygems/ext/builder.rb:192:in `build_extensions'
  /Users/max/.rvm/rubies/ruby-3.1.2/lib/ruby/3.1.0/rubygems/installer.rb:853:in `build_extensions'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/rubygems_gem_installer.rb:71:in `build_extensions'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/rubygems_gem_installer.rb:28:in `install'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/source/rubygems.rb:207:in `install'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/installer/gem_installer.rb:54:in `install'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/installer/gem_installer.rb:16:in `install_from_spec'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/installer/parallel_installer.rb:186:in `do_install'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/installer/parallel_installer.rb:177:in `block in worker_pool'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/worker.rb:62:in `apply_func'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/worker.rb:57:in `block in process_queue'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/worker.rb:54:in `loop'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/worker.rb:54:in `process_queue'
  /Users/max/.rvm/gems/ruby-3.1.2/gems/bundler-2.3.16/lib/bundler/worker.rb:91:in `block (2 levels) in create_threads'

An error occurred while installing pg (1.2.3), and Bundler cannot continue.

In Gemfile:
  pg

The other gems install fine but pg appears to be the problem. PostgreSQL is already installed on the machine and I can access it with psql command.

libpq is also installed because I have it listed when I run the brew list command.

I've investigated both of these lines in red on the Terminal and could not find a solution.

Error 1: Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

Error 2: An error occurred while installing pg (1.2.3), and Bundler cannot continue.

Please help.

CodePudding user response：

I was able to fix this by reinstalling Xcode and installing coreutils with brew install coreutils

I also had to install pg by using the pg_config path flag. gem install pg -- --with-pg-config=/path-to-pg-config/pg_config

It takes a little while then installs the pg gem.