gem install: Failed to build gem native extension (can't find header files)

For those who may be confused by the accepted answer, as I was, you also need to have the ruby headers installed [ruby-devel].

The article that saved my hide is here.

And this is the revised solution (note that I'm on Fedora 13):

yum -y install gcc mysql-devel ruby-devel rubygems
gem install -y mysql -- --with-mysql-config=/usr/bin/mysql_config

For Debian, and other distributions using Debian style packaging the ruby development headers are installed by:

sudo apt-get install ruby-dev

For Ubuntu the ruby development headers are installed by:

sudo apt-get install ruby-all-dev

If you are using a earlier version of ruby (such as 2.2), then you will need to run:

sudo apt-get install ruby2.2-dev

(where 2.2 is your desired Ruby version)

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Red Hat, Fedora:

yum -y install gcc mysql-devel ruby-devel rubygems
gem install -y mysql -- --with-mysql-config=/usr/bin/mysql_config

Debian, Ubuntu:

apt-get install libmysqlclient-dev ruby-dev
gem install mysql

Arch Linux:

pacman -S libmariadbclient
gem install mysql

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For anyone reading this in 2015: if you happened to install the package ruby2.0, you need to install the matching ruby2.0-dev to get the appropriate Ruby headers. The same goes for ruby2.1 and ruby2.2, etc. For example:

$ sudo apt-get install ruby2.2-dev

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it seems that the

yum install ruby-devel

was enough for me to perform

gem install datamapper

afterwards.

It's possible that you will need to install another packages:

yum install gcc gcc-c++

to be able to build native extensions

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MAC users may face this issue when xcode tools are not installed properly. Below is the command to get rid of the issue.

xcode-select --install

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I found the solution here.

# yum install mysql-devel gcc make
# gem install mysql -- --with-mysql-config=/usr/bin/mysql_config

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This post helped me. Thanks a lot.

On Linux (Ubuntu 12.10) I needed to run

sudo apt-get install ruby
sudo apt-get install rubygems
sudo apt-get install ruby-dev

before I could succesfully run

sudo gem install jekyll

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If you have gem installed and ruby and not able to install rails, then install ruby dev lib.

sudo apt-get install ruby-dev

It works for me. I have tried the different solution.

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Red Hat, Fedora:

sudo dnf -y install gcc-c++ redhat-rpm-config ruby-devel gcc mysql-devel rubygems

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For those that are still experiencing problems, like I have(I am using Ubuntu 16.04), I had to put in the following commands in order to get some gems like bcrypt, pg, and others installed. They are all similar to the ones above except for one.

sudo apt-get install ruby-dev -y
sudo apt-get install libpq-dev -y
sudo apt-get install libmysqlclient-dev
sudo apt-get install build-essential patch -y

This allowed me to install gems like, PG, bcrypt, and recaptcha.

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My initial solution was to resolve the above errors by installing ruby-devel, patch and rubygems.

My issue was a bit different as bcrypt 3.1.11 still had issues compiling and installing on Fedora 23. I needed additional packages. So after ensuring I had the above installed, I was still having issues:

gcc: error: conftest.c: No such file or directory

gcc: error: /usr/lib/rpm/redhat/redhat-hardened-cc1: No such file or directory

From here I had to do the following:

I ensured that I wasn't lacking any C compiler tools sudo dnf group install "C Development Tools and Libraries"

Then I ran sudo dnf install redhat-rpm-config to resolve the gcc issue listed above.

You can find a write up here on Fedore Project. You may also find answers to other needs as well.

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sudo apt-get install ruby-dev

This command solved the problem for me!

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You need following packages instaled:

ruby-dev

gcc

libffi-dev

make

Here's the command for debian distro:

 sudo apt install gcc ruby-dev rubygems libgmp-dev libgmp3-dev make 

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in openSUSE:

zypper in ruby-devel

Works to me :)

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It's necessary to install redhat-rpm-config to. I guess it solve your problem!

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This worked for me:

yum -y install gcc mysql-devel ruby-devel rubygems

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You might have messed up with the RVM.

Try to do:

\curl -sSL https://get.rvm.io | bash -s stable --rails

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Just to add path to ruby.h file in my PATH for example:

export PATH=$PATH:/usr/src/ruby-xxxxxx

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