# 13.9. Manually installing the GNU Autootools

There is enough detail in building the GNU Autotools that it warrants its own section.

Note

As noted above, you only need to read/care about this section if you are building Open MPI from a Git clone. End users installing an Open MPI distribution tarball do not need to have the GNU Autotools installed.

## 13.9.1. Use a package manager

It is recommended that you use your Linux distribution’s package manager, or Homebrew or MacPorts on macOS to install recent versions of GNU Autoconf, Automake, and Libtool.

If you cannot, keep reading in this section to see how to build and install these applications manually (i.e., download the source from the internet and build/install it yourself).

## 13.9.2. Autotools versions

The following tools are required for developers to compile Open MPI from its repository sources (users who download Open MPI tarballs do not need these tools - they are only required for developers working on the internals of Open MPI itself):

Software package | Notes | URL
--- | --- | ---
GNU m4 | See version chart below | https://ftp.gnu.org/gnu/m4/
GNU Autoconf | See version chart below | https://ftp.gnu.org/gnu/autoconf/
GNU Automake | See version chart below | https://ftp.gnu.org/gnu/automake/
GNU Libtool | See version chart below | https://ftp.gnu.org/gnu/libtool/

The table below lists the versions that are used to make nightly snapshot and official release Open MPI tarballs. Other versions of the tools may work for some (but almost certainly not all) platforms; the ones listed below are the versions that we know work across an extremely wide variety of platforms and environments.

To strengthen the above point: the core Open MPI developers typically use very, very recent versions of the GNU tools. There are known bugs in older versions of the GNU tools that Open MPI no longer compensates for (it seemed senseless to indefinitely support patches for ancient versions of Autoconf, for example).

Warning

You will have problems if you do not use recent versions of the GNU Autotools.

That being said, `autogen.pl` and `configure.ac` scripts tend to be a bit lenient and enforce slightly older minimum versions than the ones listed below. This is because such older versions still make usable Open MPI builds on many platforms - especially Linux on x86_64 with GNU compilers - and are convenient for developers whose Linux distribution may not have as recent as the versions listed below (but are recent enough to produce a working version for their platform).

To be clear: the versions listed below are required to support a wide variety of platforms and environments, and are used to make nightly and official release tarballs. When building Open MPI, YMMV when using versions older than those listed below — especially if you are not building on Linux x86_64 with the GNU compilers.

Using older versions is unsupported. If you run into problems, upgrade to at least the versions listed below.

Note

You may need to scroll right in the following table.

Open MPI | M4 | Autoconf | Automake | Libtool | Flex | Sphinx
--- | --- | --- | --- | --- | --- | ---
v1.0.x | NA | 2.58 - 2.59 | 1.7 - 1.9.6 | 1.5.16 - 1.5.22 | 2.5.4 | NA
v1.1.x | NA | 2.59 | 1.9.6 | 1.5.16 - 1.5.22 | 2.5.4 | NA
v1.2.x | NA | 2.59 | 1.9.6 | 1.5.22 - 2.1a | 2.5.4 | NA
v1.3.x | 1.4.11 | 2.63 | 1.10.1 | 2.2.6b | 2.5.4 | NA
v1.4.x | 1.4.11 | 2.63 | 1.10.3 | 2.2.6b | 2.5.4 | NA
v1.5.x for x=0-4 | 1.4.13 | 2.65 | 1.11.1 | 2.2.6b | 2.5.4 | NA
v1.5.x for x>=5 | 1.4.16 | 2.68 | 1.11.3 | 2.4.2 | 2.5.35 | NA
v1.6.x | 1.4.16 | 2.68 | 1.11.3 | 2.4.2 | 2.5.35 | NA
v1.7.x | 1.4.16 | 2.69 | 1.12.2 | 2.4.2 | 2.5.35 | NA
v1.8.x | 1.4.16 | 2.69 | 1.12.2 | 2.4.2 | 2.5.35 | NA
v1.10.x | 1.4.16 | 2.69 | 1.12.2 | 2.4.2 | 2.5.35 | NA
v2.0.x through v4.y | 1.4.17 | 2.69 | 1.15 | 2.4.6 | 2.5.35 | NA
v5.0.x | 1.4.17 | 2.69 | 1.15 | 2.4.6 | 2.5.35 | 4.2.0
Git main | 1.4.17 | 2.69 | 1.15 | 2.4.6 | 2.5.35 | 4.2.0

## 13.9.3. Checking your versions

You can check what versions of the Autotools you have installed with the following:

    shell$ m4 --version
    shell$ autoconf --version
    shell$ automake --version
    shell$ libtoolize --version

## 13.9.4. Installing the GNU Autotools from source

Note

Most operating system packaging systems (to include Homebrew and MacPorts on MacOS) install recent-enough versions of the GNU Autotools. You should generally only install the GNU Autotools manually if you can’t use your operating system packaging system to install them for you.

The GNU Autotools sources can be can be downloaded from:

- https://ftp.gnu.org/gnu/autoconf/

- https://ftp.gnu.org/gnu/automake/

- https://ftp.gnu.org/gnu/libtool/

- And if you need it: https://ftp.gnu.org/gnu/m4/

It is certainly easiest to download/build/install all four of these tools together. But note that Open MPI has no specific m4 requirements; it is only listed here because Autoconf requires minimum versions of GNU m4. Hence, you may or may not need to actually install a new version of GNU m4. That being said, if you are confused or don’t know, just install the latest GNU m4 with the rest of the GNU Autotools and everything will work out fine.

## 13.9.5. Build and install ordering

You must build and install the GNU Autotools in the following order:

1. m4

2. Autoconf

3. Automake

4. Libtool

Important

You must install the last three tools (Autoconf, Automake, Libtool) into the same prefix directory. These three tools are somewhat inter-related, and if they’re going to be used together, they must share a common installation prefix.

You can install m4 anywhere as long as it can be found in the path; it may be convenient to install it in the same prefix as the other three. Or you can use any recent-enough m4 that is in your path.

Warning

It is strongly encouraged that you do not install your new versions over the OS-installed versions. This could cause other things on your system to break. Instead, install into `$HOME/local`, or `/usr/local`, or wherever else you tend to install “local” kinds of software.

In doing so, be sure to prefix your `$PATH` with the directory where they are installed. For example, if you install into `$HOME/local`, you may want to edit your shell startup file (`.bashrc`, `.cshrc`, `.tcshrc`, etc.) to have something like

    # For bash/sh:
    export PATH=$HOME/local/bin:$PATH
    # For csh/tcsh:
    set path = ($HOME/local/bin $path)

Ensure to set your `$PATH` before you configure/build/install the four packages.

All four packages require two simple commands to build and install:

    shell$ cd M4_DIRECTORY
    shell$ ./configure --prefix=PREFIX
    shell$ make all install

Important

If you are using a shell that does not automatically re-index the `$PATH` (e.g., the `csh` or `tcsh` shells), be sure to run the `rehash` command before you install the next package so that the executables that were just installed can be found by the next package.

    # Make $PATH be re-indexed if necessary, e.g., via "rehash"
    shell$ cd AUTOCONF_DIRECTORY
    shell$ ./configure --prefix=PREFIX
    shell$ make all install

    # Make $PATH be re-indexed if necessary, e.g., via "rehash"
    shell$ cd AUTOMAKE_DIRECTORY
    shell$ ./configure --prefix=PREFIX
    shell$ make all install

    # Make $PATH be re-indexed if necessary, e.g., via "rehash"
    shell$ cd LIBTOOL_DIRECTORY
    shell$ ./configure --prefix=PREFIX
    shell$ make all install