ld: library not found for -lssl while installing mysql2 gem

Question

I changed mysql2 version in my project's Gemfile from 0.3.20 to 0.5.2. When I run bundle update mysql2 I get the following error:

Fetching mysql2 0.5.2 (was 0.3.21)
Installing mysql2 0.5.2 (was 0.3.21) with native extensions
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

    current directory: /Users/hirurg103/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/mysql2-0.5.2/ext/mysql2
/Users/hirurg103/.rbenv/versions/2.4.1/bin/ruby -I /Users/hirurg103/.rbenv/versions/2.4.1/lib/ruby/site_ruby/2.4.0 -r ./siteconf20190715-35076-13r30uh.rb extconf.rb
checking for rb_absint_size()... yes
checking for rb_absint_singlebit_p()... yes
checking for rb_wait_for_single_fd()... yes
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Using mysql_config at /usr/local/opt/[email protected]/bin/mysql_config
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checking for mysql.h... yes
checking for errmsg.h... yes
checking for SSL_MODE_DISABLED in mysql.h... no
checking for MYSQL_OPT_SSL_ENFORCE in mysql.h... no
checking for MYSQL.net.vio in mysql.h... yes
checking for MYSQL.net.pvio in mysql.h... no
checking for MYSQL_ENABLE_CLEARTEXT_PLUGIN in mysql.h... yes
checking for SERVER_QUERY_NO_GOOD_INDEX_USED in mysql.h... yes
checking for SERVER_QUERY_NO_INDEX_USED in mysql.h... yes
checking for SERVER_QUERY_WAS_SLOW in mysql.h... yes
checking for MYSQL_OPTION_MULTI_STATEMENTS_ON in mysql.h... yes
checking for MYSQL_OPTION_MULTI_STATEMENTS_OFF in mysql.h... yes
checking for my_bool in mysql.h... yes
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Don't know how to set rpath on your system, if MySQL libraries are not in path mysql2 may not load
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Setting libpath to /usr/local/opt/[email protected]/lib
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creating Makefile

current directory: /Users/hirurg103/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/mysql2-0.5.2/ext/mysql2
make "DESTDIR=" clean

current directory: /Users/hirurg103/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/mysql2-0.5.2/ext/mysql2
make "DESTDIR="
compiling client.c
compiling infile.c
compiling mysql2_ext.c
compiling result.c
compiling statement.c
linking shared-object mysql2/mysql2.bundle
ld: library not found for -lssl
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make: *** [mysql2.bundle] Error 1

make failed, exit code 2

Gem files will remain installed in /Users/hirurg103/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/gems/mysql2-0.5.2 for inspection.
Results logged to /Users/hirurg103/.rbenv/versions/2.4.1/lib/ruby/gems/2.4.0/extensions/x86_64-darwin-18/2.4.0-static/mysql2-0.5.2/gem_make.out

An error occurred while installing mysql2 (0.5.2), and Bundler cannot continue.
Make sure that `gem install mysql2 -v '0.5.2' --source 'https://rubygems.org/'` succeeds before bundling.

My setup:

mysql: Ver 14.14 Distrib 5.6.42, for osx10.14 (x86_64) using EditLine wrapper

OS: MacOS Mojave 10.14.2

How can I fix this error?

Answer 1

I was able to solve this problem with the following command:

gem install mysql2 -v '0.5.2' -- --with-cflags=\"-I/usr/local/opt/openssl/include\" --with-ldflags=\"-L/usr/local/opt/openssl/lib\"

and then

bundle install

UPDATE:

OpenSSL 1.0 reached EOL on 2019-12-31. After Mac OS and Homebrew packages upgrade you will need to specify paths to [email protected]:

gem install mysql2 -v 0.5.2 -- --with-cflags=\"-I/usr/local/opt/[email protected]/include\" --with-ldflags=\"-L/usr/local/opt/[email protected]/lib\"

Answer 2

Homebrew moved files around, here is what works now 2022-04:

• Macbook Arm M1
• MacOS Monterey 12.3.1
• Homebrew 3.4.7

gem install mysql2 -v '0.5.3' -- \
--with-cflags=\"-I/opt/homebrew/opt/openssl/include\" \
--with-ldflags=\"-L/opt/homebrew/opt/openssl/lib\"

Answer 3

On macOS Big Sur I used the following commands to get the mysql2 gem installed:

brew install openssl
gem install mysql2 -v '0.5.3' -- --with-ldflags=-L/usr/local/opt/openssl/lib