Check out example codes for "linker command failed with exit code 1 ruby". It will help you in understanding the concepts better.

Code Example 1

$ bundle config --local build.mysql2 "--with-cppflags=-I/usr/local/opt/openssl/include"
$ bundle config --local build.mysql2 "--with-ldflags=-L/usr/local/opt/openssl/lib"

Code Example 2

export LDFLAGS="-L/usr/local/opt/openssl/lib"
  export CPPFLAGS="-I/usr/local/opt/openssl/include"

Learn ReactJs, React Native from akashmittal.com